Immunodeficiency Disorder Flashcards
State in which the immune system’s ability to flight infectious disease in compromised
Can occur if any of the four major components of the immune system are compromised:
B cells
T cells
Phagocytes
Complement
Immunodeficiency
Recurrent infections with pyogenic bacteria indicate a b-cell deficiency
Recurrent infections with fungi, viruses or Protozoa indicate a t-cell deficiency
Immunodeficiency
Genetic susceptibility to infections since childhood
IgA deficiency, Bruton’s XLA
Primary immunodeficiency
Acquired susceptibility to infection as a result of external processes or diseases
(Malnutrition, aging, drugs, AIDS)
Secondary immunodeficiency
B cell disorders
- X-linked agammaglobulinemia/Bruton’s Agammaglobulinemia
- Selective IgA Deficiency
- Common variable immunodeficiency
T cell disorders
- Di George Syndrome
2. Chronic mucocutaneous candidiasis
Combined B and T cell disorders
- Severe combined immunodeficiency (SCID)
- Wiskott-Aldrich Syndrome
- Ataxia-Telangiectasia
Phagocyte disorders
- Chronic Granulomatous Disease
- Chediak-Higashi Syndrome
- Leukocyte adhesion deficiency (LAD)
Complement disorders
- C2 deficiency
2. C3 deficiency
Very low levels of all immunoglobulins Virtual absence if B cells due to tyrosine kinase mutation Cell-mediated immunity is normal Male infants at about 6 months of age Recurrent pyogenic bacterial infections Recurrent enteroviral infections Recurrent giardiasis Tx: pooled gamma globulin
X-linked Agammaglobulinemia or Bruton’s Agammaglobulinemia
Failure of isotope switching
Recurrent bacterial sinus and lung infections
Tx: do not treat with gamma globulins preparations
Selective IgA Deficiency
Defect in B-cell maturation to plasma cells
Diagnosis of exclusion
Recurrent pyogenic bacterial infections
Most common form of severe antibody deficiency affecting both children and adults
Tx: pooled gamma globulin
Common variable immunodeficiency
Profound deficit of T cells
Failure of development of thymus and parathyroid a
Due to a defect in 3rd and 4th pharyngeal pouches
Humoral immunity is normal
Tetany due to hypocalcemis
Severe viral, fungal, or Protozoal infections during infancy
Tx: transplant of fetal thymus
Di George Syndrome
Cardiac defect (TOF) Abnormal facies Thymic aphasia Cleft palate Hypocalcemia 22q11.2 chromosomal deletion
Di George Syndrome
Specific T-cell deficiency for Candida albicans Other T-cell and B-cell functions are normal Recurrent candidiasis (skin, mucous membranes) in children Tx: azole antifungal drugs
Chronic mucocutaneous candidiasis
X-linked defect in IL-2 receptors in T cells
Autosomal: ADA deficiency
Recurrent bacterial, viral, fungal and protozoal infection in early infancy (3 months of age)
Tx: enclosure in plastic bubble
Bone marrow transplant
Severe combined immunodeficiency
X-linked (affects male infants)
Inability to mount IgM response
Mutation in WASP gene for actin filament assembly
Recurrent pyogenic infections, eczema, and bleeding due to thrombocytopenia
Bone marrow transplant
Wiskott-Aldrich Syndrome
Autosomal recessive disease Mutations in DNA repair enzymes IgA deficiency Ataxia, Telangiectasia, recurrent infections by 2 years of age Tx: supportive management
Ataxia-Telangiectasia
Lack of NADPH oxidase activity
Failure of oxidase burst
Normal B and T cell activity
Recurrent infections with catalase-positive bacteria, fungi
Widespread granulomas of unknown etiology
Tx: antibiotic chemoprophylaxis
Chronic Granulomatous Disease
Autosomal recessive disease
Failure of phagolysosomal fusion
Faulty microtubules impair neutrophil chemotaxis
Recurrent pyogenic infections caused by staphylococci and streptococci
Tx: antibiotics
Chediak-Higashi Syndrome
Autosomal recessive disease Mutation in integrins Defective adhesion (LFA-1) proteins on the surface of phagocytes Severe pyogenic infections in infancy Delayed separation of umbilical cord Tx: antibiotics, bone marrow transplant
Leukocyte Adhesion Deficiency (LAD)
Specific deficiency in C5-C9
Inability to form membrane-attack complexes
Bacteremia with Neisseria meningitidis or Neisseria gonorrhoeae
TX: vaccination
C2 Deficiency
Specific deficiency in C5-C9
Inability to form membrane-attack complexes
Bacteremia with Neisseria meningitidis or Neisseria gonorrhoeae
TX: vaccination
C3 Deficiency
Decreased supply of amino acids
Decreased synthesis of IgG and complement
Malnourished child with recurrent pyogenic infections
TX: Antibiotics, nutritional support
Malnutrition
