Megacolon is a severe, abnormal dilatation of the colon and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease. Toxic megacolon is an acute form of megacolon with systemic toxicity and carries the highest morbidity and mortality. Common symptoms include abdominal distention, pain, bloody diarrhea, or obstipation. Diagnosis depends on the underlying cause and is usually established with a combination of the patient’s history, laboratory findings, and imaging studies. Patients with chronic megacolon may require laxatives, enemas, and bowel training. Management for acute megacolon includes supportive care, decompression, and potential surgery.
MegacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon is a severe dilatation of the colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy secondary to impaired motilityMotilityThe motor activity of the gastrointestinal tract.Gastrointestinal Motility or an inflammatory process. The condition is classified based on the time course and duration:
Exact incidenceIncidenceThe number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time.Measures of Disease Frequency is unknown.
All ages may be affected.
IncidenceIncidenceThe number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time.Measures of Disease Frequency depends on the underlying disease:
Congenital aganglionic megacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon:
1 in 5,000 live births
Men > women
Toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon:
4.3% in patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship with Clostridioides difficile, previously known as Clostridium difficileClostridium difficileA common inhabitant of the colon flora in human infants and sometimes in adults. The type species clostridioides difficile is formerly known as Clostridium difficile. It is a causative agent for clostridioides infections and is associated with pseudomembranous enterocolitis in patients receiving antibiotic therapy.Clostridia, colitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis
Toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon (non-obstructive colonic dilation with systemic toxicityToxicityDosage Calculation)
IBD
Ulcerative colitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis
Crohn’s disease
Ischemic colitisIschemic colitisInflammation of the colon due to colonic ischemia resulting from alterations in systemic circulation or local vasculature.Large Bowel Obstruction
Infectious colitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis
C. difficile colitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis (most common)
SalmonellaSalmonellaSalmonellae are gram-negative bacilli of the family Enterobacteriaceae. Salmonellae are flagellated, non-lactose-fermenting, and hydrogen sulfide-producing microbes. Salmonella enterica, the most common disease-causing species in humans, is further classified based on serotype as typhoidal (S. typhi and paratyphi) and nontyphoidal (S. enteritidis and typhimurium). Salmonella
ShigellaShigellaShigella is a genus of gram-negative, non-lactose-fermenting facultative intracellular bacilli. Infection spreads most commonly via person-to-person contact or through contaminated food and water. Humans are the only known reservoir.Shigella
CampylobacterCampylobacterCampylobacter (“curved bacteria”) is a genus of thermophilic, S-shaped, gram-negative bacilli. There are many species of Campylobacter, with C. jejuni and C. coli most commonly implicated in human disease. Campylobacter
Escherichia coli O157Escherichia coli O157A verocytotoxin-producing serogroup belonging to the o subfamily of Escherichia coli which has been shown to cause severe food-borne disease. A strain from this serogroup, serotype h7, which produces shiga toxins, has been linked to human disease outbreaks resulting from contamination of foods by E. coli o157 from bovine origin.Diarrheagenic E. coli
CytomegalovirusCytomegalovirusCMV is a ubiquitous double-stranded DNA virus belonging to the Herpesviridae family. CMV infections can be transmitted in bodily fluids, such as blood, saliva, urine, semen, and breast milk. The initial infection is usually asymptomatic in the immunocompetent host, or it can present with symptoms of mononucleosis. Cytomegalovirus (CMV) colitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis (usually in immunodeficient patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship)
Entamoeba histolyticaEntamoeba HistolyticaA species of parasitic protozoa causing entamoebiasis and amebic dysentery (dysentery, amebic). Characteristics include a single nucleus containing a small central karyosome and peripheral chromatin that is finely and regularly beaded.Amebicides
Acute colonic pseudo-obstructionColonic pseudo-obstructionFunctional obstruction of the colon leading to megacolon in the absence of obvious colonic diseases or mechanical obstruction. When this condition is acquired, acute, and coexisting with another medical condition (trauma, surgery, serious injuries or illness, or medication), it is called ogilvie’s syndrome.Imaging of the Intestines (Ogilvie’s syndromeOgilvie’s syndromeA type of ileus, a functional not mechanical obstruction of the intestines. This syndrome is caused by a large number of disorders involving the smooth muscles or the nervous system.Large Bowel Obstruction)
Severe systemic illness
Surgery (most commonly from cesarean section or hip surgery)
OpiatesOpiatesOpiates are drugs that are derived from the sap of the opium poppy. Opiates have been used since antiquity for the relief of acute severe pain. Opioids are synthetic opiates with properties that are substantially similar to those of opiates.Opioid Analgesics
AnticholinergicsAnticholinergicsAnticholinergic drugs block the effect of the neurotransmitter acetylcholine at the muscarinic receptors in the central and peripheral nervous systems. Anticholinergic agents inhibit the parasympathetic nervous system, resulting in effects on the smooth muscle in the respiratory tract, vascular system, urinary tract, GI tract, and pupils of the eyes. Anticholinergic Drugs
CalciumCalciumA basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Electrolytes channel blockers
Congenital aganglionic megacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon (Hirschsprung diseaseHirschsprung DiseaseHirschsprung disease (HD), also known as congenital aganglionosis or congenital megacolon, is a congenital anomaly of the colon caused by the failure of neural crest-derived ganglion cells to migrate into the distal colon. The lack of innervation always involves the rectum and extends proximally and contiguously over variable distances. MHirschsprung Disease):
Most cases associated with mutations in the RET proto-oncogene
Sometimes associated with other genetic syndromes:
Down’s syndrome
Multiple endocrine neoplasiaMultiple endocrine neoplasiaMultiple endocrine neoplasia syndromes are autosomal dominant inherited conditions characterized by 2 or more hormone-producing tumors involving the endocrine organs. There are different types of MEN, namely MEN1-4. Multiple Endocrine Neoplasia (MEN) type 2A or 2B
Waardenburg syndromeWaardenburg syndromeRare, autosomal dominant disease with variable penetrance and several known clinical types. Characteristics may include depigmentation of the hair and skin, congenital deafness, heterochromia iridis, medial eyebrow hyperplasia, hypertrophy of the nasal root, and especially dystopia canthorum. The underlying cause may be defective development of the neural crest (neurocristopathy). Waardenburg’s syndrome may be closely related to piebaldism. Klein-waardenburg syndrome refers to a disorder that also includes upper limb abnormalities.Hirschsprung Disease
Acquired
Chronic idiopathicIdiopathicDermatomyositisconstipationConstipationConstipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation (most common)
Spinal cordSpinal cordThe spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy injury
Parkinson’s disease
Chagas diseaseChagas diseaseInfection with the protozoan parasite trypanosoma cruzi, a form of trypanosomiasis endemic in central and south america. It is named after the brazilian physician carlos chagas, who discovered the parasite. Infection by the parasite (positive serologic result only) is distinguished from the clinical manifestations that develop years later, such as destruction of parasympathetic ganglia; chagas cardiomyopathy; and dysfunction of the esophagus or colon.Trypanosoma cruzi/Chagas disease (through destruction of enteric neuronsNeuronsThe basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the nervous system.Nervous System: Histology)
SclerodermaSclerodermaScleroderma (systemic sclerosis) is an autoimmune condition characterized by diffuse collagen deposition and fibrosis. The clinical presentation varies from limited skin involvement to diffuse involvement of internal organs. Scleroderma
Systemic lupus erythematosusSystemic lupus erythematosusSystemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected.Systemic Lupus Erythematosus
DermatomyositisDermatomyositisA subacute or chronic inflammatory disease of muscle and skin, marked by proximal muscle weakness and a characteristic skin rash. The illness occurs with approximately equal frequency in children and adults. The skin lesions usually take the form of a purplish rash (or less often an exfoliative dermatitis) involving the nose, cheeks, forehead, upper trunk, and arms. The disease is associated with a complement mediated intramuscular microangiopathy, leading to loss of capillaries, muscle ischemia, muscle-fiber necrosis, and perifascicular atrophy. The childhood form of this disease tends to evolve into a systemic vasculitis. Dermatomyositis may occur in association with malignant neoplasms.Paraneoplastic Syndromes and polymyositisPolymyositisPolymyositis (PM) is an autoimmune inflammatory myopathy caused by T cell-mediated muscle injury. The etiology of PM is unclear, but there are several genetic and environmental associations. Polymyositis is most common in middle-aged women and rarely affects children. Polymyositis
Toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon[1,6,7]
Mucosal inflammationInflammationInflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation:
Causes the release of inflammatory mediators → induction of nitric oxideNitric OxideA free radical gas produced endogenously by a variety of mammalian cells, synthesized from arginine by nitric oxide synthase. Nitric oxide is one of the endothelium-dependent relaxing factors released by the vascular endothelium and mediates vasodilation. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic guanylate cyclase and thus elevates intracellular levels of cyclic gmp.Pulmonary Hypertension Drugs synthase → nitric oxideNitric OxideA free radical gas produced endogenously by a variety of mammalian cells, synthesized from arginine by nitric oxide synthase. Nitric oxide is one of the endothelium-dependent relaxing factors released by the vascular endothelium and mediates vasodilation. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic guanylate cyclase and thus elevates intracellular levels of cyclic gmp.Pulmonary Hypertension Drugs generation by macrophagesMacrophagesThe relatively long-lived phagocytic cell of mammalian tissues that are derived from blood monocytes. Main types are peritoneal macrophages; alveolar macrophages; histiocytes; kupffer cells of the liver; and osteoclasts. They may further differentiate within chronic inflammatory lesions to epithelioid cells or may fuse to form foreign body giant cells or langhans giant cells.Innate Immunity: Phagocytes and Antigen Presentation and smooth muscle cells → smooth muscle relaxation → colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy dilation
Extends to the smooth muscle layer → paralysis of smooth muscle → colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy dilation
Potential precipitating factors:
HypokalemiaHypokalemiaHypokalemia is defined as plasma potassium (K+) concentration < 3.5 mEq/L. Homeostatic mechanisms maintain plasma concentration between 3.5-5.2 mEq/L despite marked variation in dietary intake. Hypokalemia can be due to renal losses, GI losses, transcellular shifts, or poor dietary intake.Hypokalemia
Medications:
OpiatesOpiatesOpiates are drugs that are derived from the sap of the opium poppy. Opiates have been used since antiquity for the relief of acute severe pain. Opioids are synthetic opiates with properties that are substantially similar to those of opiates.Opioid Analgesics
AnticholinergicsAnticholinergicsAnticholinergic drugs block the effect of the neurotransmitter acetylcholine at the muscarinic receptors in the central and peripheral nervous systems. Anticholinergic agents inhibit the parasympathetic nervous system, resulting in effects on the smooth muscle in the respiratory tract, vascular system, urinary tract, GI tract, and pupils of the eyes. Anticholinergic Drugs
Antidepressants
Bowel preparation solutions or barium
Abrupt discontinuation of steroidsSteroidsA group of polycyclic compounds closely related biochemically to terpenes. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (sterols), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus.Benign Liver Tumors or mesalamine in IBD
Acute colonic pseudo-obstructionColonic pseudo-obstructionFunctional obstruction of the colon leading to megacolon in the absence of obvious colonic diseases or mechanical obstruction. When this condition is acquired, acute, and coexisting with another medical condition (trauma, surgery, serious injuries or illness, or medication), it is called ogilvie’s syndrome.Imaging of the Intestines[2,8]
Progressive distention and ↑ tension on the colonic wall
Congenital aganglionic megacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon[3,4,5]
Failure of neural crestNeural crestThe two longitudinal ridges along the primitive streak appearing near the end of gastrulation during development of nervous system (neurulation). The ridges are formed by folding of neural plate. Between the ridges is a neural groove which deepens as the fold become elevated. When the folds meet at midline, the groove becomes a closed tube, the neural tube.Hirschsprung Disease cell migration during the embryonic intestinal development → distal colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy is aganglionic and nonfunctioning → distention of the colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy proximal to the aganglionic segment
Nerve plexuses affected:
Meissner (submucosal plexus)
Auerbach (myenteric plexusMyenteric plexusOne of two ganglionated neural networks which together form the enteric nervous system. The myenteric (Auerbach’s) plexus is located between the longitudinal and circular muscle layers of the gut. Its neurons project to the circular muscle, to other myenteric ganglia, to submucosal ganglia, or directly to the epithelium, and play an important role in regulating and patterning gut motility.Gastrointestinal Neural and Hormonal Signaling)
The amount of colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy affected varies.
Chronic acquired megacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon[2,5]
Incompletely understood
Neurologic or muscular dysfunction → disruption in normal peristalsisPeristalsisA movement, caused by sequential muscle contraction, that pushes the contents of the intestines or other tubular organs in one direction.Gastrointestinal Motility → progressive colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy dilation
MegacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon and megarectum from chronic constipationConstipationConstipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation are associated with:
↑ Rectal complianceComplianceDistensibility measure of a chamber such as the lungs (lung compliance) or bladder. Compliance is expressed as a change in volume per unit change in pressure.Veins: Histology and elasticityElasticityResistance and recovery from distortion of shape.Skeletal Muscle Contraction
Toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon:
Sudden cessation of diarrheaDiarrheaDiarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea should also be concerning.
Congenital aganglionic megacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon:
Majority will present in the neonatal period.
Bilious emesis
Failure to pass meconiumMeconiumThe thick green-to-black mucilaginous material found in the intestines of a full-term fetus. It consists of secretions of the intestinal glands; bile pigments; fatty acids; amniotic fluid; and intrauterine debris. It constitutes the first stools passed by a newborn.Prenatal and Postnatal Physiology of the Neonate or stool
Feeding intolerance and failure to thriveFailure to ThriveFailure to thrive (FTT), or faltering growth, describes suboptimal weight gain and growth in children. The majority of cases are due to inadequate caloric intake; however, genetic, infectious, and oncological etiologies are also common. Failure to Thrive
Toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon:
TachycardiaTachycardiaAbnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia.Sepsis in Children
FeverFeverFever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever
HypotensionHypotensionHypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension
Possible evidence of peritonitisPeritonitisInflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the peritoneal cavity via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the abdominal cavity itself through rupture or abscess of intra-abdominal organs.Penetrating Abdominal Injury
RigidityRigidityContinuous involuntary sustained muscle contraction which is often a manifestation of basal ganglia diseases. When an affected muscle is passively stretched, the degree of resistance remains constant regardless of the rate at which the muscle is stretched. This feature helps to distinguish rigidity from muscle spasticity.Megacolon
Congenital aganglionic megacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon:
Tight anal sphincter
Release of stool and gas with digital examination
Diagnosis
Laboratory evaluation[1,6,7,13]
These studies help evaluate the severity of the disease, complications, and potential causes.
General findings:
HypokalemiaHypokalemiaHypokalemia is defined as plasma potassium (K+) concentration < 3.5 mEq/L. Homeostatic mechanisms maintain plasma concentration between 3.5-5.2 mEq/L despite marked variation in dietary intake. Hypokalemia can be due to renal losses, GI losses, transcellular shifts, or poor dietary intake.Hypokalemia (gastrointestinal loss)
Metabolic acidosisAcidosisA pathologic condition of acid accumulation or depletion of base in the body. The two main types are respiratory acidosis and metabolic acidosis, due to metabolic acid build up.Respiratory Acidosis and ↑ lactic acid are concerning for colonic ischemiaIschemiaA hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation.Ischemic Cell Damage.
↑ blood ureaUreaA compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.Urea CyclenitrogenNitrogenAn element with the atomic symbol n, atomic number 7, and atomic weight [14. 00643; 14. 00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth’s atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Urea Cycle (BUN):creatinine ratio (dehydrationDehydrationThe condition that results from excessive loss of water from a living organism.Volume Depletion and Dehydration)
Findings in toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon:
AnemiaAnemiaAnemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types (due to gastrointestinal blood loss)
Culture for bacteriaBacteriaBacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology and parasites
C. difficiletoxin
Imaging[1,2,5,6]
Abdominal X-rayX-rayPenetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source.Pulmonary Function Tests:[7,14,17,18]
ColonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy dilatation (> 6 cm)
Significant stool retention may be seen.
May show transition zoneTransition ZonePediatric Gastrointestinal Abnormalities between dilated colonDilated colonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon and narrow rectumRectumThe rectum and anal canal are the most terminal parts of the lower GI tract/large intestine that form a functional unit and control defecation. Fecal continence is maintained by several important anatomic structures including rectal folds, anal valves, the sling-like puborectalis muscle, and internal and external anal sphincters. Rectum and Anal Canal: Anatomy in Hirschsprung diseaseHirschsprung DiseaseHirschsprung disease (HD), also known as congenital aganglionosis or congenital megacolon, is a congenital anomaly of the colon caused by the failure of neural crest-derived ganglion cells to migrate into the distal colon. The lack of innervation always involves the rectum and extends proximally and contiguously over variable distances. MHirschsprung Disease
Air-fluid levels can be present.
Toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon findings:
Right and transverse colonTransverse colonThe segment of large intestine between ascending colon and descending colon. It passes from the right colic flexure across the abdomen, then turns sharply at the left colonic flexure into the descending colon.Colon, Cecum, and Appendix: Anatomy dilation are the most prominent.
Loss of normal haustral pattern
Mucosal ulcerations with islands of edematous mucosa
Computed tomography (CT) with oral and intravenous (IV) contrast:[7,8,17,18]
Colonic dilatation (> 6 cm)
Free air indicates perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis.
May show fecal impaction or stool burden in cases associated with chronic constipationConstipationConstipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation
Acute colonic pseudo-obstructionColonic pseudo-obstructionFunctional obstruction of the colon leading to megacolon in the absence of obvious colonic diseases or mechanical obstruction. When this condition is acquired, acute, and coexisting with another medical condition (trauma, surgery, serious injuries or illness, or medication), it is called ogilvie’s syndrome.Imaging of the Intestines: possible transition zoneTransition ZonePediatric Gastrointestinal Abnormalities without a mechanical cause for obstruction
Toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon:
Loss of haustral pattern
Segmental colonic wall thinning
Nodular pseudopolyps (deep mucosal ulcerations)
IschemiaIschemiaA hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation.Ischemic Cell Damage (if present)
RadiopaqueRadiopaqueAn object of high density that blocks X-rays (looks white)X-rays marker study
Wireless motilityMotilityThe motor activity of the gastrointestinal tract.Gastrointestinal MotilitycapsuleCapsuleAn envelope of loose gel surrounding a bacterial cell which is associated with the virulence of pathogenic bacteria. Some capsules have a well-defined border, whereas others form a slime layer that trails off into the medium. Most capsules consist of relatively simple polysaccharides but there are some bacteria whose capsules are made of polypeptides.Bacteroides
Computed tomography image of toxic megacolon secondary to C. difficile infection This CT shows colonic distention of 8.8 cm.
Image: “Abdominal CT scan” by Jeroen Kerstens et al. License: CC BY 4.0
Abdominal X-ray of a 2-month-old patient with congenital aganglionic megacolon (Hirschsprung disease) This image shows dilated loops of the small bowel and colon.
Image: “Simple abdominal radiography” by Mariana Tresoldi das Neves Romaneli et al. License: CC BY 4.0
X-ray image of a patient with toxic megacolon The X-ray was performed in the standing position and shows colonic air-fluid levels in the epigastric region and the splenic flexure.
Image: “Plain X-ray” by Jeroen Kerstens et al. License: CC BY 4.0
Other studies[1,2,4–6]
EndoscopyEndoscopyProcedures of applying endoscopes for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. Transluminal, to examine or perform surgery on the interior parts of the body.Gastroesophageal Reflux Disease (GERD):[7,16,18]
For toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon:
Complete colonoscopyColonoscopyEndoscopic examination, therapy or surgery of the luminal surface of the colon.Colorectal Cancer Screening is avoided due to the high risk of perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis
Limited sigmoidoscopySigmoidoscopyEndoscopic examination, therapy or surgery of the sigmoid flexure.Colorectal Cancer Screening may help establish an underlying etiology (C. difficile CMV, IBD)
ColonoscopyColonoscopyEndoscopic examination, therapy or surgery of the luminal surface of the colon.Colorectal Cancer Screening can rule out obstruction.
BiopsyBiopsyRemoval and pathologic examination of specimens from the living body.Ewing Sarcoma can be performed if the etiology is unknown.
Studies for Hirschsprung disease:[15,16,18]
Rectal biopsyBiopsyRemoval and pathologic examination of specimens from the living body.Ewing Sarcoma:
Less accurate in neonates and people with chronic constipationConstipationConstipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation
Contrast enema: transition zoneTransition ZonePediatric Gastrointestinal Abnormalities between narrowed rectumRectumThe rectum and anal canal are the most terminal parts of the lower GI tract/large intestine that form a functional unit and control defecation. Fecal continence is maintained by several important anatomic structures including rectal folds, anal valves, the sling-like puborectalis muscle, and internal and external anal sphincters. Rectum and Anal Canal: Anatomy and proximal dilated colonDilated colonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon
Colonoscopy image showing a severe ulcer and pseudomembrane at the descending colon in a patient with toxic megacolon
Image: “Colonoscopy” by Department of Gastroenterological Surgery, Clinical Research Institute Cancer Research Division, National Kyushu Medical Center, Fukuoka, Japan. License: CC BY 4.0
Diagnostic criteria for toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon[7]
Radiographic evidence of colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy distention (> 6 cm)
And ≥ 3 of the following:
FeverFeverFever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever (> 38.6°C (101.5°F))
TachycardiaTachycardiaAbnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia.Sepsis in Children (> 120 beats/min)
LeukocytosisLeukocytosisA transient increase in the number of leukocytes in a body fluid.West Nile Virus (> 10.5 x 109 /L)
AnemiaAnemiaAnemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types
HypotensionHypotensionHypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension
Management
Toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon
General management:[7,14,17,18]
PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship should be monitored in an intensive care unit (ICUICUHospital units providing continuous surveillance and care to acutely ill patients.West Nile Virus).
Discontinue any antimotility, opiatesOpiatesOpiates are drugs that are derived from the sap of the opium poppy. Opiates have been used since antiquity for the relief of acute severe pain. Opioids are synthetic opiates with properties that are substantially similar to those of opiates.Opioid Analgesics, or anticholinergicAnticholinergicAnticholinergic drugs block the effect of the neurotransmitter acetylcholine at the muscarinic receptors in the central and peripheral nervous systems. Anticholinergic agents inhibit the parasympathetic nervous system, resulting in effects on the smooth muscle in the respiratory tract, vascular system, urinary tract, GI tract, and pupils of the eyes. Anticholinergic Drugs medications.
Cover for potential peritonitisPeritonitisInflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the peritoneal cavity via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the abdominal cavity itself through rupture or abscess of intra-abdominal organs.Penetrating Abdominal Injury from perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis
Ensure gram-negative and anaerobic coverage
Maneuvers to decrease colonic distention:
Placement of rectal tube
Patient ambulation
“Knee-elbow maneuver” in the prone position
Rotating a bedbound patient
Initiating enteral feeding as soon as there are signs of improvement helps promote colonic motilityMotilityThe motor activity of the gastrointestinal tract.Gastrointestinal Motility.
C. difficilecolitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis:[7,11,12]
Causative antibiotics should be withdrawn immediately.
IV steroidsSteroidsA group of polycyclic compounds closely related biochemically to terpenes. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (sterols), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus.Benign Liver Tumors are contraindicated.
Preferred regimen: oral vancomycinVancomycinAntibacterial obtained from streptomyces orientalis. It is a glycopeptide related to ristocetin that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Glycopeptides (500‒2,000 mg/day) and IV metronidazoleMetronidazoleA nitroimidazole used to treat amebiasis; vaginitis; trichomonas infections; giardiasis; anaerobic bacteria; and treponemal infections.Pyogenic Liver Abscess (1,500 mg/day):
Adequate colonic concentration of oral vancomycinVancomycinAntibacterial obtained from streptomyces orientalis. It is a glycopeptide related to ristocetin that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Glycopeptides may not always be achieved because of poor intestinal motilityIntestinal MotilityGastrointestinal Motility.
Alternative delivery options for vancomycinVancomycinAntibacterial obtained from streptomyces orientalis. It is a glycopeptide related to ristocetin that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Glycopeptides:
Enemas (may fail to treat right side of colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy; risk of perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis)
Intracolonic infusion with colonoscopyColonoscopyEndoscopic examination, therapy or surgery of the luminal surface of the colon.Colorectal Cancer Screening (also carries the risk of perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis)
Fidaxomicin:
Narrow-spectrum macrolide antibiotic used for refractory and recurrent C. difficile colitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis
A few case reports show that it can be used as a salvage therapy for toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon refractory to vancomycinVancomycinAntibacterial obtained from streptomyces orientalis. It is a glycopeptide related to ristocetin that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Glycopeptides and metronidazoleMetronidazoleA nitroimidazole used to treat amebiasis; vaginitis; trichomonas infections; giardiasis; anaerobic bacteria; and treponemal infections.Pyogenic Liver Abscess.
Fecal microbiota transplantation:
When not responsive to antibiotic therapy alone
Successful outcomes reported when combined with vancomycinVancomycinAntibacterial obtained from streptomyces orientalis. It is a glycopeptide related to ristocetin that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Glycopeptides.
Serial treatments may be needed.
IBD:[7,17,18]
5-Aminosalicylic acid and sulfasalazineSulfasalazineA drug that is used in the management of inflammatory bowel diseases. Its activity is generally considered to lie in its metabolic breakdown product, 5-aminosalicylic acid released in the colon.Sulfonamides and Trimethoprim should be avoided and resumed only after resolution of toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon.
1st-line: IV glucocorticoidsGlucocorticoidsGlucocorticoids are a class within the corticosteroid family. Glucocorticoids are chemically and functionally similar to endogenous cortisol. There are a wide array of indications, which primarily benefit from the antiinflammatory and immunosuppressive effects of this class of drugs.Glucocorticoids (initiate immediately):
HydrocortisoneHydrocortisoneThe main glucocorticoid secreted by the adrenal cortex. Its synthetic counterpart is used, either as an injection or topically, in the treatment of inflammation, allergy, collagen diseases, asthma, adrenocortical deficiency, shock, and some neoplastic conditions.Immunosuppressants 100 mg IV every 6–8 hours
DexamethasoneDexamethasoneAn anti-inflammatory 9-fluoro-glucocorticoid.Antiemetics, prednisolonePrednisoloneA glucocorticoid with the general properties of the corticosteroids. It is the drug of choice for all conditions in which routine systemic corticosteroid therapy is indicated, except adrenal deficiency states.Immunosuppressants, and methylprednisoloneMethylprednisoloneA prednisolone derivative with similar anti-inflammatory action.Immunosuppressants have also been used.
Note: Clinical signs of systemic toxicityToxicityDosage Calculation and perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis can be masked by steroidsSteroidsA group of polycyclic compounds closely related biochemically to terpenes. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (sterols), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus.Benign Liver Tumors.
2nd-line: infliximabInfliximabA chimeric monoclonal antibody to tnf-alpha that is used in the treatment of rheumatoid arthritis; ankylosing spondylitis; psoriatic arthritis and Crohn’s disease.Disease-Modifying Antirheumatic Drugs (DMARDs) or cyclosporineCyclosporineA cyclic undecapeptide from an extract of soil fungi. It is a powerful immunosupressant with a specific action on T-lymphocytes. It is used for the prophylaxis of graft rejection in organ and tissue transplantation.Immunosuppressants:
Started if no improvement after 3 days of IV glucocorticoidsGlucocorticoidsGlucocorticoids are a class within the corticosteroid family. Glucocorticoids are chemically and functionally similar to endogenous cortisol. There are a wide array of indications, which primarily benefit from the antiinflammatory and immunosuppressive effects of this class of drugs.Glucocorticoids
InfliximabInfliximabA chimeric monoclonal antibody to tnf-alpha that is used in the treatment of rheumatoid arthritis; ankylosing spondylitis; psoriatic arthritis and Crohn’s disease.Disease-Modifying Antirheumatic Drugs (DMARDs) preferred; cyclosporineCyclosporineA cyclic undecapeptide from an extract of soil fungi. It is a powerful immunosupressant with a specific action on T-lymphocytes. It is used for the prophylaxis of graft rejection in organ and tissue transplantation.Immunosuppressants if infliximabInfliximabA chimeric monoclonal antibody to tnf-alpha that is used in the treatment of rheumatoid arthritis; ankylosing spondylitis; psoriatic arthritis and Crohn’s disease.Disease-Modifying Antirheumatic Drugs (DMARDs) is not tolerated
CyclosporineCyclosporineA cyclic undecapeptide from an extract of soil fungi. It is a powerful immunosupressant with a specific action on T-lymphocytes. It is used for the prophylaxis of graft rejection in organ and tissue transplantation.Immunosuppressants effective for ulcerative colitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis but not Crohn’s colitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis
Surgical management:[7,9,10]
Indications for surgery:
No clinical improvement within 48–72 hours
PerforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis
PeritonitisPeritonitisInflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the peritoneal cavity via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the abdominal cavity itself through rupture or abscess of intra-abdominal organs.Penetrating Abdominal Injury or worsening abdominal exam
Worsening colonic distention
IschemiaIschemiaA hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation.Ischemic Cell Damage or necrosisNecrosisThe death of cells in an organ or tissue due to disease, injury or failure of the blood supply.Ischemic Cell Damage
Massive colonic hemorrhage
Worsening systemic toxicityToxicityDosage Calculation (feverFeverFever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever, hemodynamic instability, or worsening mental status)
Abdominal compartment syndromeAbdominal Compartment SyndromeAcute Pancreatitis or abdominal hypertensionHypertensionHypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension
Surgical procedures:
IBD:
Subtotal colectomy with end ileostomyIleostomySurgical creation of an external opening into the ileum for fecal diversion or drainage. This replacement for the rectum is usually created in patients with severe inflammatory bowel diseases. Loop (continent) or tube (incontinent) procedures are most often employed.Large Bowel Obstruction preferred (leaves rectal stump)
Rectal stump allows for subsequent stoma takedown and reconstruction
There is a small risk of rectal stump blowout and pelvic sepsisSepsisSystemic inflammatory response syndrome with a proven or suspected infectious etiology. When sepsis is associated with organ dysfunction distant from the site of infection, it is called severe sepsis. When sepsis is accompanied by hypotension despite adequate fluid infusion, it is called septic shock.Sepsis and Septic Shock → can be prevented by creating mucous fistulaFistulaAbnormal communication most commonly seen between two internal organs, or between an internal organ and the surface of the body.Anal Fistula or putting a drain in the stump
C. difficilecolitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis:
Total abdominal colectomy with end ileostomyIleostomySurgical creation of an external opening into the ileum for fecal diversion or drainage. This replacement for the rectum is usually created in patients with severe inflammatory bowel diseases. Loop (continent) or tube (incontinent) procedures are most often employed.Large Bowel Obstruction
Colonic lavage with diverting loop ileostomyIleostomySurgical creation of an external opening into the ileum for fecal diversion or drainage. This replacement for the rectum is usually created in patients with severe inflammatory bowel diseases. Loop (continent) or tube (incontinent) procedures are most often employed.Large Bowel Obstruction → allows subsequent vancomycinVancomycinAntibacterial obtained from streptomyces orientalis. It is a glycopeptide related to ristocetin that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.Glycopeptides administration through ileostomyIleostomySurgical creation of an external opening into the ileum for fecal diversion or drainage. This replacement for the rectum is usually created in patients with severe inflammatory bowel diseases. Loop (continent) or tube (incontinent) procedures are most often employed.Large Bowel Obstruction (if no perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis or necrosisNecrosisThe death of cells in an organ or tissue due to disease, injury or failure of the blood supply.Ischemic Cell Damage)
Surgical findings for toxic megacolon related to C. difficile colitis
Image: “Toxic megacolon” by University of Pittsburgh Department of Pathology. License: CC BY 3.0
Acute colonic pseudo-obstructionColonic pseudo-obstructionFunctional obstruction of the colon leading to megacolon in the absence of obvious colonic diseases or mechanical obstruction. When this condition is acquired, acute, and coexisting with another medical condition (trauma, surgery, serious injuries or illness, or medication), it is called ogilvie’s syndrome.Imaging of the Intestines[8,14,18]
Without peritonitisPeritonitisInflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the peritoneal cavity via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the abdominal cavity itself through rupture or abscess of intra-abdominal organs.Penetrating Abdominal Injury
Cecal diameter < 12 cm
Includes:
Rectal tube for decompression
Stop offending medications (opiatesOpiatesOpiates are drugs that are derived from the sap of the opium poppy. Opiates have been used since antiquity for the relief of acute severe pain. Opioids are synthetic opiates with properties that are substantially similar to those of opiates.Opioid Analgesics, anticholinergicsAnticholinergicsAnticholinergic drugs block the effect of the neurotransmitter acetylcholine at the muscarinic receptors in the central and peripheral nervous systems. Anticholinergic agents inhibit the parasympathetic nervous system, resulting in effects on the smooth muscle in the respiratory tract, vascular system, urinary tract, GI tract, and pupils of the eyes. Anticholinergic Drugs, calciumCalciumA basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Electrolytes channel blockers).
Treat underlying illness.
Follow with serial physical exams and X-raysX-raysX-rays are high-energy particles of electromagnetic radiation used in the medical field for the generation of anatomical images. X-rays are projected through the body of a patient and onto a film, and this technique is called conventional or projectional radiography. X-rays every 12–24 hours.
Pharmacologic interventions:
Indications:
No improvement in 48–72 hours
Cecal diameter > 12 cm
MethylnaltrexoneMethylnaltrexoneOpioid Analgesics: if the obstruction is precipitated by opiatesOpiatesOpiates are drugs that are derived from the sap of the opium poppy. Opiates have been used since antiquity for the relief of acute severe pain. Opioids are synthetic opiates with properties that are substantially similar to those of opiates.Opioid Analgesics
IV neostigmineNeostigmineA cholinesterase inhibitor used in the treatment of myasthenia gravis and to reverse the effects of muscle relaxants such as gallamine and tubocurarine. Neostigmine, unlike physostigmine, does not cross the blood-brain barrier.Cholinomimetic Drugs (acetylcholinesterase inhibitor):
Bolus IV dosing: 2‒5 mg over 3‒5 minutes
89% respond to single dose.
40%‒100% for whom the 1st dose fails will respond to a 2nd dose.
Continuous IV infusion (0.4 mg/hr) has been effective in some studies.
PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship need to be in monitored setting → immediate access to atropineAtropineAn alkaloid, originally from atropa belladonna, but found in other plants, mainly solanaceae. Hyoscyamine is the 3(s)-endo isomer of atropine.Anticholinergic Drugs if bradycardiaBradycardiaBradyarrhythmia is a rhythm in which the heart rate is less than 60/min. Bradyarrhythmia can be physiologic, without symptoms or hemodynamic change. Pathologic bradyarrhythmia results in reduced cardiac output and hemodynamic instability causing syncope, dizziness, or dyspnea.Bradyarrhythmias develops
Other considerations:
GlycopyrrolateGlycopyrrolateA muscarinic antagonist used as an antispasmodic, in some disorders of the gastrointestinal tract, and to reduce salivation with some anesthetics.Anticholinergic Drugs reduces side effects, such as hypersalivation and bronchospasmBronchospasmAsthma Drugs.
Daily administration of polyethylene glycolPolyethylene GlycolLaxatives after neostigmineNeostigmineA cholinesterase inhibitor used in the treatment of myasthenia gravis and to reverse the effects of muscle relaxants such as gallamine and tubocurarine. Neostigmine, unlike physostigmine, does not cross the blood-brain barrier.Cholinomimetic Drugs decreases recurrence.
Absolute contraindicationsContraindicationsA condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks).Noninvasive Ventilation:
Urinary obstruction
Intestinal obstructionIntestinal obstructionAny impairment, arrest, or reversal of the normal flow of intestinal contents toward the anal canal.Ascaris/Ascariasis
PeritonitisPeritonitisInflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the peritoneal cavity via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the abdominal cavity itself through rupture or abscess of intra-abdominal organs.Penetrating Abdominal Injury
Relative contraindicationsContraindicationsA condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks).Noninvasive Ventilation:
BradycardiaBradycardiaBradyarrhythmia is a rhythm in which the heart rate is less than 60/min. Bradyarrhythmia can be physiologic, without symptoms or hemodynamic change. Pathologic bradyarrhythmia results in reduced cardiac output and hemodynamic instability causing syncope, dizziness, or dyspnea.Bradyarrhythmias
AsthmaAsthmaAsthma is a chronic inflammatory respiratory condition characterized by bronchial hyperresponsiveness and airflow obstruction. The disease is believed to result from the complex interaction of host and environmental factors that increase disease predisposition, with inflammation causing symptoms and structural changes. Patients typically present with wheezing, cough, and dyspnea. Asthma
Peptic ulcerPeptic ulcerPeptic ulcer disease (PUD) refers to the full-thickness ulcerations of duodenal or gastric mucosa. The ulcerations form when exposure to acid and digestive enzymes overcomes mucosal defense mechanisms. The most common etiologies include Helicobacter pylori (H. pylori) infection and prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs). Peptic Ulcer Disease disease
Renal impairment
AcidosisAcidosisA pathologic condition of acid accumulation or depletion of base in the body. The two main types are respiratory acidosis and metabolic acidosis, due to metabolic acid build up.Respiratory Acidosis
Recent myocardial infarctionMyocardial infarctionMI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms.Myocardial Infarction
Colonoscopic decompression:
Indications:
No response to neostigmineNeostigmineA cholinesterase inhibitor used in the treatment of myasthenia gravis and to reverse the effects of muscle relaxants such as gallamine and tubocurarine. Neostigmine, unlike physostigmine, does not cross the blood-brain barrier.Cholinomimetic Drugs
ContraindicationsContraindicationsA condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks).Noninvasive Ventilation to neostigmineNeostigmineA cholinesterase inhibitor used in the treatment of myasthenia gravis and to reverse the effects of muscle relaxants such as gallamine and tubocurarine. Neostigmine, unlike physostigmine, does not cross the blood-brain barrier.Cholinomimetic Drugs
Has a 3% perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis rate
Procedure considerations:
Should be performed with water infusion on unprepped colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy
Use minimal insufflation with carbon dioxide (rather than air).
Attempt to reach the distal transverse colonTransverse colonThe segment of large intestine between ascending colon and descending colon. It passes from the right colic flexure across the abdomen, then turns sharply at the left colonic flexure into the descending colon.Colon, Cecum, and Appendix: Anatomy (at least).
PeritonitisPeritonitisInflammation of the peritoneum lining the abdominal cavity as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the peritoneal cavity via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the abdominal cavity itself through rupture or abscess of intra-abdominal organs.Penetrating Abdominal Injury (ischemiaIschemiaA hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation.Ischemic Cell Damage or perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis)
Procedures:
Cecostomy tube placementTube placementSurgical procedure involving the creation of an opening (stoma) into the chest cavity for drainage; used in the treatment of pleural effusion; pneumothorax; hemothorax; and empyema.Thoracic Surgery or percutaneous cecostomy (decompressive procedures appropriate if no colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: AnatomyischemiaIschemiaA hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation.Ischemic Cell Damage or perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis)
Total abdominal colectomy with anastomosis (for a stable patient with no ischemiaIschemiaA hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation.Ischemic Cell Damage or perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis) or end ileostomyIleostomySurgical creation of an external opening into the ileum for fecal diversion or drainage. This replacement for the rectum is usually created in patients with severe inflammatory bowel diseases. Loop (continent) or tube (incontinent) procedures are most often employed.Large Bowel Obstruction
Supportive treatment as needed (hydration, electrolyte correction)
Stop offending medications (opiatesOpiatesOpiates are drugs that are derived from the sap of the opium poppy. Opiates have been used since antiquity for the relief of acute severe pain. Opioids are synthetic opiates with properties that are substantially similar to those of opiates.Opioid Analgesics, anticholinergicsAnticholinergicsAnticholinergic drugs block the effect of the neurotransmitter acetylcholine at the muscarinic receptors in the central and peripheral nervous systems. Anticholinergic agents inhibit the parasympathetic nervous system, resulting in effects on the smooth muscle in the respiratory tract, vascular system, urinary tract, GI tract, and pupils of the eyes. Anticholinergic Drugs).
Nasogastric or rectal tube decompression, if requiring hospitalizationHospitalizationThe confinement of a patient in a hospital.Delirium
Empty the bowel.
Manual disimpaction may be required for fecal impaction.
SuppositoriesSuppositoriesMedicated dosage forms that are designed to be inserted into the rectal, vaginal, or urethral orifice of the body for absorption. Generally, the active ingredients are packaged in dosage forms containing fatty bases such as cocoa butter, hydrogenated oil, or glycerogelatin that are solid at room temperature but melt or dissolve at body temperature.Large Bowel Obstruction
For severe cases that are unresponsive to medical management
Hirschsprung diseaseHirschsprung DiseaseHirschsprung disease (HD), also known as congenital aganglionosis or congenital megacolon, is a congenital anomaly of the colon caused by the failure of neural crest-derived ganglion cells to migrate into the distal colon. The lack of innervation always involves the rectum and extends proximally and contiguously over variable distances. MHirschsprung Disease:
Definitive therapy
Resection of aganglionic segment with primary anastomosis
Mechanical large bowel obstructionBowel obstructionAny impairment, arrest, or reversal of the normal flow of intestinal contents toward the anal canal.Ascaris/Ascariasis: interruption in the flowFlowBlood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls.Vascular Resistance, Flow, and Mean Arterial Pressure of intraluminal contents caused by intrinsic or extrinsic compressionCompressionBlunt Chest Trauma of the colonic lumen. Common etiologies include colorectal cancerColorectal cancerColorectal cancer (CRC) is the 2nd leading cause of cancer-related deaths in the United States. Colorectal cancer is a heterogeneous disease that arises from genetic and epigenetic abnormalities, with influence from environmental factors. Colorectal Cancer and volvulusVolvulusA volvulus is the twisting or axial rotation of a portion of the bowel around its mesentery. The most common site of volvulus in adults is the colon; most frequently the sigmoid volvulus. Patients typically present with symptoms of bowel obstruction such as abdominal pain, distension, vomiting, and constipation/obstipation. Volvulus. PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship present with abdominal distentionAbdominal distentionMegacolon, obstipationObstipationLarge Bowel Obstruction, nauseaNauseaAn unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses.Antiemetics, and vomitingVomitingThe forcible expulsion of the contents of the stomach through the mouth.Hypokalemia. The diagnosis is established with imaging. Management includes bowel rest, decompression, and surgery.
Small bowel obstructionBowel obstructionAny impairment, arrest, or reversal of the normal flow of intestinal contents toward the anal canal.Ascaris/Ascariasis: an interruption of intraluminal contents through the small bowelSmall bowelThe small intestine is the longest part of the GI tract, extending from the pyloric orifice of the stomach to the ileocecal junction. The small intestine is the major organ responsible for chemical digestion and absorption of nutrients. It is divided into 3 segments: the duodenum, the jejunum, and the ileum.Small Intestine: Anatomy due to a mechanical or functional problem. PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship present with abdominal painAbdominal PainAcute Abdomen, distention, nauseaNauseaAn unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses.Antiemetics, and vomitingVomitingThe forcible expulsion of the contents of the stomach through the mouth.Hypokalemia. Imaging will show involvement of the small bowelSmall bowelThe small intestine is the longest part of the GI tract, extending from the pyloric orifice of the stomach to the ileocecal junction. The small intestine is the major organ responsible for chemical digestion and absorption of nutrients. It is divided into 3 segments: the duodenum, the jejunum, and the ileum.Small Intestine: Anatomy, although the colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy may also be distended in functional obstruction. Most cases will resolve with supportive care.
AppendicitisAppendicitisAppendicitis is the acute inflammation of the vermiform appendix and the most common abdominal surgical emergency globally. The condition has a lifetime risk of 8%. Characteristic features include periumbilical abdominal pain that migrates to the right lower quadrant, fever, anorexia, nausea, and vomiting.Appendicitis:inflammationInflammationInflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation of the appendixAppendixA worm-like blind tube extension from the cecum.Colon, Cecum, and Appendix: Anatomy. Early appendicitisAppendicitisAppendicitis is the acute inflammation of the vermiform appendix and the most common abdominal surgical emergency globally. The condition has a lifetime risk of 8%. Characteristic features include periumbilical abdominal pain that migrates to the right lower quadrant, fever, anorexia, nausea, and vomiting.Appendicitis can present with diffuse colicky painPainAn unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons.Pain: Types and Pathways, but painPainAn unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons.Pain: Types and Pathways and tenderness eventually localize to the right lower quadrantRight lower quadrantAnterior Abdominal Wall: Anatomy. Diagnosis is established by CT scan. Treatment includes antibiotics and surgery.
DiverticulitisDiverticulitisInflammation of a diverticulum or diverticula.Diverticular Disease:inflammationInflammationInflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation of the colonic diverticula. PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship present with crampy lower abdominal painAbdominal PainAcute Abdomen and may have constipationConstipationConstipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation. DiverticulitisDiverticulitisInflammation of a diverticulum or diverticula.Diverticular Disease is frequently associated with feverFeverFever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever and leukocytosisLeukocytosisA transient increase in the number of leukocytes in a body fluid.West Nile Virus. A CT scan shows the characteristic inflammatory findings. Treatment includes bowel rest, antibiotics, and occasionally surgery.
Billing and Coding
Diagnosis Codes:
These codes are used to diagnose megacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon, an abnormal dilation of the colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy. The codes can specify if it is a toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon, which is an acute, life-threatening complication of inflammatory bowel disease or colitisColitisInflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever.Pseudomembranous Colitis.
Coding System
Code
Description
ICD-10-CM
K59.31
Toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon
ICD-10-CM
K59.39
Other specified functional disorder of intestine
SNOMED CT
25162002
MegacolonMegacolonMegacolon is a severe, abnormal dilatation of the colon, and is classified as acute or chronic. There are many etiologies of megacolon, including neuropathic and dysmotility conditions, severe infections, ischemia, and inflammatory bowel disease.Megacolon (disorder)
Procedures/Interventions:
This CPT code is for a subtotal colectomy, a surgical procedure to remove a large portion of the colonColonThe large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy, which is the definitive treatment for toxic megacolonToxic megacolonAn acute form of megacolon, severe pathological dilatation of the colon. It is associated with clinical conditions such as ulcerative colitis; Crohn disease; amebic dysentery; or Clostridium enterocolitis.Megacolon to prevent perforationPerforationA pathological hole in an organ, blood vessel or other soft part of the body, occurring in the absence of external force.Esophagitis.
Coding System
Code
Description
CPT
44150
Colectomy, total, abdominal, without proctectomy; with ileostomyIleostomySurgical creation of an external opening into the ileum for fecal diversion or drainage. This replacement for the rectum is usually created in patients with severe inflammatory bowel diseases. Loop (continent) or tube (incontinent) procedures are most often employed.Large Bowel Obstruction or ileoproctostomy
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