Myeloperoxidase Deficiency

Epidemiology and Etiology

Epidemiology

• Myeloperoxidase Myeloperoxidase Acute Myeloid Leukemia ( MPO MPO Acute Myeloid Leukemia) deficiency is the most common primary phagocyte disorder.
• Incidence Incidence The 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: 1 in 1400–2000 individuals in the United States
• Morbidity Morbidity The proportion of patients with a particular disease during a given year per given unit of population. Measures of Health Status:
  • Severe infection occurs in < 5% of cases
  • Generally, infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease occur only in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with concomitant diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus mellitus.

Etiology

Genetic mutation Mutation Genetic mutations are errors in DNA that can cause protein misfolding and dysfunction. There are various types of mutations, including chromosomal, point, frameshift, and expansion mutations. Types of Mutations:

• MPO MPO Acute Myeloid Leukemia gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics: 17q22-23 
• Normal MPO MPO Acute Myeloid Leukemia function: enzyme that generates hypochlorous acid (HOCl) in neutrophils Neutrophils Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. Innate Immunity: Phagocytes and Antigen Presentation and monocytes Monocytes Large, phagocytic mononuclear leukocytes produced in the vertebrate bone marrow and released into the blood; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles. Innate Immunity: Phagocytes and Antigen Presentation

Primary MPO MPO Acute Myeloid Leukemia deficiency: 

• Most common form
• Variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables expression and penetrance Penetrance The percent frequency with which a dominant or homozygous recessive gene or gene combination manifests itself in the phenotype of the carriers. Familial Juvenile Polyposis
• Most patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship are compound heterozygotes, with different mutations on each allele Allele Variant forms of the same gene, occupying the same locus on homologous chromosomes, and governing the variants in production of the same gene product. Basic Terms of Genetics.

Acquired (secondary) MPO MPO Acute Myeloid Leukemia deficiency: 

• Less common
• May arise from somatic mutations 
• Affects only a proportion of neutrophils Neutrophils Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. Innate Immunity: Phagocytes and Antigen Presentation 
• Transient (resolves with improvement of the underlying cause)
• Causes:
  • Diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus mellitus
  • Pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care
  • Iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements deficiency
  • Renal transplantation
  • Thrombotic diseases
  • Lead poisoning Lead poisoning Poisoning that results from chronic or acute ingestion, injection, inhalation, or skin absorption of lead or lead compounds. Metal Poisoning (Lead, Arsenic, Iron)
  • Obstructive jaundice Obstructive jaundice Hepatocellular Carcinoma (HCC) and Liver Metastases
  • Hematologic malignancies and disorders
  • Severe infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease 
  • Cytotoxic Cytotoxic Parvovirus B19 and antiinflammatory medications

Pathophysiology and Clinical Presentation

Pathophysiology

Neutrophils Neutrophils Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. Innate Immunity: Phagocytes and Antigen Presentation are the 1st line of defense against pathogens:

• During phagocytosis Phagocytosis The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (phagocytes). Innate Immunity: Phagocytes and Antigen Presentation, neutrophils Neutrophils Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. Innate Immunity: Phagocytes and Antigen Presentation undergo respiratory burst Respiratory burst A large increase in oxygen uptake by neutrophils and most types of tissue macrophages through activation of an NADPH-cytochrome b-dependent oxidase that reduces oxygen to a superoxide. Individuals with an inherited defect in which the oxidase that reduces oxygen to superoxide is decreased or absent often die as a result of recurrent bacterial infections. Leukocyte Adhesion Deficiency Type 1.
• Activation of nicotinamide adenosine Adenosine A nucleoside that is composed of adenine and d-ribose. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter. Class 5 Antiarrhythmic Drugs dinucleotide phosphate Phosphate Inorganic salts of phosphoric acid. Electrolytes ( NADPH NADPH Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5′-phosphate (nmn) coupled by pyrophosphate linkage to the 5′-phosphate adenosine 2. Pentose Phosphate Pathway) oxidase Oxidase Neisseria and superoxide dismutase → production of superoxide, hydrogen peroxide, and other reactive oxygen species Reactive oxygen species Molecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen intermediates include singlet oxygen; superoxides; peroxides; hydroxyl radical; and hypochlorous acid. They contribute to the microbicidal activity of phagocytes, regulation of signal transduction and gene expression, and the oxidative damage to nucleic acids; proteins; and lipids. Nonalcoholic Fatty Liver Disease (ROS)
• MPO MPO Acute Myeloid Leukemia converts hydrogen peroxide to HOCl (amplifies toxicity Toxicity Dosage Calculation of ROS)
• Pathogens killed in phagolysosome Phagolysosome Chédiak-Higashi Syndrome

MPO-deficient neutrophils Neutrophils Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. Innate Immunity: Phagocytes and Antigen Presentation:

• Have variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables ability to kill bacteria Bacteria Bacteria 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
• Are unable to kill certain fungi Fungi A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including mushrooms; yeasts; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies. Mycology:
  • Candida albicans Candida albicans A unicellular budding fungus which is the principal pathogenic species causing candidiasis (moniliasis). Candida/Candidiasis
  • C. krusei
  • C. stellatoidea
  • C. tropicalis

Clinical presentation

• Most individuals are asymptomatic and have no increased frequency of infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease.
• Severe infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease are uncommon (< 5% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship):
  • Usually due to Candida Candida Candida is a genus of dimorphic, opportunistic fungi. Candida albicans is part of the normal human flora and is the most common cause of candidiasis. The clinical presentation varies and can include localized mucocutaneous infections (e.g., oropharyngeal, esophageal, intertriginous, and vulvovaginal candidiasis) and invasive disease (e.g., candidemia, intraabdominal abscess, pericarditis, and meningitis). Candida/Candidiasis 
  • Increased risk with diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus mellitus or malignancy Malignancy Hemothorax

Diagnosis and Management

Diagnosis

• Histochemical staining:
  • Performed on a blood smear 
  • Neutrophils Neutrophils Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. Innate Immunity: Phagocytes and Antigen Presentation will lack MPO MPO Acute Myeloid Leukemia (normally seen as azurophilic granules).
• Immunohistochemistry
• Flow cytometry Flow cytometry Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake. X-linked Agammaglobulinemia measures reactive oxygen intermediates.

Management

Because most patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship are asymptomatic, no specific treatment for MPO MPO Acute Myeloid Leukemia deficiency is required.

• Prophylactic antibiotics are not indicated.
• Prompt treatment of infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease, particularly in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus
• Avoid unnecessary or prolonged use of antibiotics or steroids Steroids A 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 (↑ risk of fungal infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease).

Differential Diagnosis

• Leukocyte adhesion Leukocyte adhesion Leukocyte Adhesion Deficiency Type 1 deficiency type 1 Type 1 Spinal Muscular Atrophy: inherited condition resulting in a lack of CD18 CD18 Cell-surface glycoprotein beta-chains that are non-covalently linked to specific alpha-chains of the cd11 family of leukocyte-adhesion molecules (receptors, leukocyte-adhesion). A defect in the gene encoding cd18 causes leukocyte-adhesion deficiency syndrome. Leukocyte Adhesion Deficiency Type 1 expression on neutrophils Neutrophils Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. Innate Immunity: Phagocytes and Antigen Presentation. This deficiency leads to a decrease in the ability of neutrophils Neutrophils Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. Innate Immunity: Phagocytes and Antigen Presentation to migrate from the blood vessels. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with this condition will have recurrent infections Recurrent infections Common Variable Immunodeficiency (CVID), delayed wound healing Wound healing Wound healing is a physiological process involving tissue repair in response to injury. It involves a complex interaction of various cell types, cytokines, and inflammatory mediators. Wound healing stages include hemostasis, inflammation, granulation, and remodeling. Wound Healing, and an elevated neutrophil count. Leukocyte adhesion Leukocyte adhesion Leukocyte Adhesion Deficiency Type 1 deficiency type 1 Type 1 Spinal Muscular Atrophy is not associated with oculocutaneous albinism Oculocutaneous albinism Heterogeneous group of autosomal recessive disorders comprising at least four recognized types, all having in common varying degrees of hypopigmentation of the skin, hair, and eyes. The two most common are the tyrosinase-positive and tyrosinase-negative types. Albinism. The diagnosis is confirmed with flow cytometry Flow cytometry Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake. X-linked Agammaglobulinemia demonstrating a deficiency in CD18 CD18 Cell-surface glycoprotein beta-chains that are non-covalently linked to specific alpha-chains of the cd11 family of leukocyte-adhesion molecules (receptors, leukocyte-adhesion). A defect in the gene encoding cd18 causes leukocyte-adhesion deficiency syndrome. Leukocyte Adhesion Deficiency Type 1. Hematopoietic stem cell transplantation Hematopoietic stem cell transplantation Transfer of hematopoietic stem cells from bone marrow or blood between individuals within the same species (homologous transplantation) or transfer within the same individual (autologous transplantation). Hematopoietic stem cell transplantation has been used as an alternative to bone marrow transplantation in the treatment of a variety of neoplasms. Organ Transplantation is the treatment of choice.
• Chronic granulomatous disease Granulomatous disease A defect of leukocyte function in which phagocytic cells ingest but fail to digest bacteria, resulting in recurring bacterial infections with granuloma formation. When chronic granulomatous disease is caused by mutations in the cybb gene, the condition is inherited in an X-linked recessive pattern. When chronic granulomatous disease is caused by cyba, ncf1, ncf2, or ncf4 gene mutations, the condition is inherited in an autosomal recessive pattern. Common Variable Immunodeficiency (CVID): consequence of defective phagocytic cells. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with this disease will have recurrent infections Recurrent infections Common Variable Immunodeficiency (CVID), abscesses, and granulomatous lesions of multiple organs. Hypergammaglobulinemia Hypergammaglobulinemia An excess of gamma-globulins in the serum due to chronic infections or paraproteinemias. Autoimmune Hepatitis may be seen. The diagnosis is made with neutrophil function testing for superoxide production. Antimicrobial prophylaxis Prophylaxis Cephalosporins, interferon gamma, granulocyte transfusion Granulocyte transfusion Severe Congenital Neutropenia, and hematopoietic stem cell transplantation Hematopoietic stem cell transplantation Transfer of hematopoietic stem cells from bone marrow or blood between individuals within the same species (homologous transplantation) or transfer within the same individual (autologous transplantation). Hematopoietic stem cell transplantation has been used as an alternative to bone marrow transplantation in the treatment of a variety of neoplasms. Organ Transplantation are potential management options.
• Severe congenital neutropenia Congenital neutropenia Severe Congenital Neutropenia: rare disease resulting from genetic mutations Genetic Mutations Carcinogenesis that affect myelopoiesis Myelopoiesis Formation of myeloid cells from the pluripotent hematopoietic stem cells in the bone marrow via myeloid stem cells. Myelopoiesis generally refers to the production of leukocytes in blood, such as monocytes and granulocytes. This process also produces precursor cells for macrophage and dendritic cells found in the lymphoid tissue. White Myeloid Cells: Histology. This condition manifests in infancy with life-threatening bacterial infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease. Neutropenia Neutropenia Neutrophils are an important component of the immune system and play a significant role in the eradication of infections. Low numbers of circulating neutrophils, referred to as neutropenia, predispose the body to recurrent infections or sepsis, though patients can also be asymptomatic. Neutropenia is found on laboratory evaluation, often with an elevated monocyte count. A bone marrow Bone marrow The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells. Bone Marrow: Composition and Hematopoiesis biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma will also aid in the diagnosis. Management includes granulocyte colony-stimulating factor Granulocyte colony-stimulating factor A glycoprotein of mw 25 kda containing internal disulfide bonds. It induces the survival, proliferation, and differentiation of neutrophilic granulocyte precursor cells and functionally activates mature blood neutrophils. Among the family of colony-stimulating factors, G-CSF is the most potent inducer of terminal differentiation to granulocytes and macrophages of leukemic myeloid cell lines. White Myeloid Cells: Histology and hematopoietic stem cell transplantation Hematopoietic stem cell transplantation Transfer of hematopoietic stem cells from bone marrow or blood between individuals within the same species (homologous transplantation) or transfer within the same individual (autologous transplantation). Hematopoietic stem cell transplantation has been used as an alternative to bone marrow transplantation in the treatment of a variety of neoplasms. Organ Transplantation.
• Chediak-Higashi syndrome ( CHS CHS Cannabinoids): autosomal recessive Autosomal recessive Autosomal inheritance, both dominant and recessive, refers to the transmission of genes from the 22 autosomal chromosomes. Autosomal recessive diseases are only expressed when 2 copies of the recessive allele are inherited. Autosomal Recessive and Autosomal Dominant Inheritance disorder caused by mutations affecting a lysosomal trafficking regulator Lysosomal trafficking regulator Chédiak-Higashi Syndrome protein. This protein plays a crucial role in the inability of neutrophils Neutrophils Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes. Innate Immunity: Phagocytes and Antigen Presentation to kill phagocytosed microbes. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with CHS CHS Cannabinoids exhibit recurrent pyogenic infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease, easy bleeding and bruising, and neurologic manifestations. This syndrome is also associated with oculocutaneous albinism Oculocutaneous albinism Heterogeneous group of autosomal recessive disorders comprising at least four recognized types, all having in common varying degrees of hypopigmentation of the skin, hair, and eyes. The two most common are the tyrosinase-positive and tyrosinase-negative types. Albinism. The diagnosis is made by analysis of the patient’s blood or bone marrow smear Bone marrow smear Chédiak-Higashi Syndrome and genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies. The treatment of choice is allogeneic hematopoietic cell transplantation.
• Hyper IgE IgE An immunoglobulin associated with mast cells. Overexpression has been associated with allergic hypersensitivity. Immunoglobulins: Types and Functions syndrome: hereditary primary immunodeficiency Immunodeficiency Chédiak-Higashi Syndrome disease characterized by recurrent skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions abscesses, pneumonia Pneumonia Pneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy. Pneumonia with pneumatocele, and eczematous dermatitis Dermatitis Any inflammation of the skin. Atopic Dermatitis (Eczema). The diagnosis is made by finding elevated serum IgE IgE An immunoglobulin associated with mast cells. Overexpression has been associated with allergic hypersensitivity. Immunoglobulins: Types and Functions levels and can be confirmed with genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies. Management includes prophylactic antibiotics and interferon-gamma for severe infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease.