Pediatric Vomiting and Diarrhea

Image: “A human male baby, crying.” by Evan-Amos – Own work. License: Public Domain

Pediatric Vomiting

Vomiting is a symptom rather than a diagnosis. It can be secondary to gastrointestinal causes or rarely secondary to distant organ system such as vomiting secondary to increased intracranial pressure. The whole symptom constellation with associated complaints and examination findings aided by a meticulous history is often crucial in the correct interpretation of vomiting and its subsequent treatment.

Various etiologies leading to vomiting can be segregated as per age of the child:

Another way of classifying vomiting is according to the responsible system; the same is tabulated below:

Etio-pathogenesis

Vomiting is a vagal mediated reflex and actually a protective mechanism. It is mediated by peripheral receptors and central controlling units. The central processing units are situated in the medulla near the obex of the fourth ventricle.

Vomiting is composed of nausea, retching and conscious expulsion of gastrointestinal contents. It is a culmination of synchronized contraction of intercostals muscles, diaphragm and abdominal muscles with the sequential relaxation of the esophageal sphincter.

Diagnosis of Pediatric Vomiting

Vomiting is a symptom and a potential harbinger of an underlying serious disorder.

Extensive history taking, followed by a relevant clinical examination, can often narrow down the system involved.

Salient points to be essentially covered in history are:

• Demographic details of the patient: age, sex, place of residence (important in cases of epidemics and food poisoning)
• Onset/duration/progress of complaints
• Association of food intake
• Any other associated complaints: fever, earache, headache, abdominal pain, dysphagia
• Review of systems, past medical and surgical history, drug intake, drug allergy, social and nutritional history
• Nature of the vomitus (projectile/non-projectile), color, contents, painful/painless

Color and content of vomitus are often of crucial significance. A rough estimate of the level of obstruction can be discerned based on these findings alone as follows:

History should aid in performing localized relevant examination.

It is of paramount importance to assess hydration status in every pediatric patient with vomiting. The red-flag signs of dehydration should usher emergent, rapid, aggressive fluid management. These are documented as follows:

• Reduced skin turgor
• Sunken eyes, often tearless
• Dry mucous membranes
• Sunken fontanelle
• Tachycardia, tachypnea
• Prolonged capillary refill time

Investigations

The list of differentials formed at the end of clinical assessment help guide the investigations to be performed. Some frequent investigations and their relevance are:

Treatment of Pediatric Vomiting

Once the cause is identified, there are two phases of management of vomiting – namely to resuscitate and stabilize the patient in an emergent manner with subsequent treatment of the inciting factor.

Pediatric Diarrhea

The normal frequency of bowel movement is about thrice daily up to alternate daily. Excess of daily stool volume more than 10 ml/kg/body weight per day is an objective definition of diarrhea.

The working definition involves liquid consistency, increased frequency and increased volume of stools. Twice the normal frequency of motions for an infant, and more than three liquid stools per day in older children, is considered abnormal.

These definitions are rather to be used precariously, always taking into account age, diet and weight of the child.

The presence of certain substances in stools is never normal and should initiate appropriate workup and subsequent management. These are:

• Mucus
• Fresh blood – red
• Altered blood – black
• Foul smell
• Runny, watery stools

Certain subsets of pediatric population are more prone to develop diarrhea. The relevant significant ones are:

• Lack of breastfeeding
• Malnutrition
• Measles
• Attendance to child care centers
• Exposure to unhygienic circumstances
• Poor maternal education
• Immunodeficient individuals.

Classification

Pediatric diarrhea can be classified variously as follows:

Based on temporal relation:

• Acute: for less than 14 days
• Chronic/persistent: for more than 14 days

Based on mechanism:

• Osmotic: stool volume depends on diet and decreases with fasting
• Secretary: stool volume is increased and does not vary with diet
• Motility disturbance: often diagnosed in older children
• Mucosal inflammation: secondary to invasive bacteria and inflammatory bowel disease
• Mixed secretary-osmotic: seen in infections like Rotavirus

Based on clinical features:

• Acute watery diarrhea:
  • Most common, usually self-limiting. The most crucial concern is the maintenance of hydration status.
  • Rota-virus, Vibro cholerae
• Acute bloody diarrhea:
  • Also known as dysentery; the culmination of intestinal mucosal erosion by invasive species. The most significant complications are sepsis, HUS (Hemolytic Uremic Syndrome), malnutrition and dehydration.
  • Entamoeba histolytica, Shigella species.

Based on etiology:

• Infectious: secondary to infection
• Mal-absorptive: increased stool output with excess of fluid and electrolytes

Infectious Diarrhea

Viral infectious diarrhea is the most prevalent pediatric diarrhea. Pyogenic follows next in line. The key to diagnosis is to recover organism in stools. Enzyme immunoassay is helpful in some cases.

A short summary of infectious diarrhea is presented below:

Diagnosis of Pediatric Diarrhea

Diarrhea is deceptive and not always innocuous and benign in nature. Constant vigilance and prevention of dehydration is a must. Correct, timely diagnosis is the key.

The diagnostic strategy begins with expert history taking and performing a relevant clinical examination.

The relevant key points to be focused upon in history are as follows:

• Demographics of the child
• Onset, duration, progress of diarrhea
• Nature, content, color, smell, consistency, frequency of stools
• Presence of blood, worms, mucus, foreign body in the stools
• Associated complaints: fever, abdominal pain, earache, history of measles, vaccination, convulsions
• Treatment history

The relevant physical examination can then be carried out in the right perspective as suggested by a focused history is very helpful.  The assessment of hydration status forms the heart of a physical examination in pediatric diarrhea.

In children, the signs and symptoms of dehydration are not always loud and clear. A simplified grading of dehydration status based on clinical acumen is as follows:

Assessment and subsequent desired treatment of dehydration is the most significant life-saving act that medical personnel is expected to perform in the management of pediatric diarrhea.

Investigations

Ancillary tests are often helpful in reaching the correct diagnosis, but they do not bring about a drastic change in the acute management of pediatric diarrhea. They are definitely relevant in the long run to know the exact etiology and rule out predisposing factors, if any.

These tests can be summarized as follows:

Treatment of Pediatric Diarrhea

It is worth reiterating that the acute management of diarrhea revolves around the emergent maintenance of hydration status. The long-term management consists of the determination of the cause, inciting factors and correction of the same to prevent a relapse.

The treatment strategy is summarized as follows:

Summary

• Vomiting by itself is more of a symptom than a diagnosis. Meticulous history taking and a relevant physical exam with pertinent ancillary tests performed help in making the right diagnosis. Treatment follows accordingly.
• Pediatric diarrhea can be variously classified based on etiology, mechanism and temporal relation.
• The key factor in the treatment of both pediatric vomiting and diarrhea is the maintenance of the hydration status.
• Long-term management consists of the evaluation of the inciting factor, treatment of the same and corrective steps taken to avoid relapses.

Review Questions on Pediatric Vomiting and Diarrhea

The correct answers can be found below the references.

1. Which of the following statements is false?

1. Otitis media can cause vomiting.
2. Meticulous history taking and the relevant physical exam is the key to making the correct diagnosis of vomiting.
3. Projectile non-bilious vomiting can be caused by pyloric stenosis.
4. Zinc is detrimental and should be avoided in children with diarrhea.

2. Which of the following infectious agent causes diarrhea with convulsions?

1. E.coli
2. Salmonella
3. Shigella
4. Yersinia.

3. Which of the following signs indicate severe dehydration?

1. Deeply sunken eyes, minimal capillary refill
2. Thirsty child with normal pulse rate
3. Vomiting child with easy skin recoil
4. Tachycardia with normal urine output.