Immunodeficiency Conditions 2024 PDF

Immunodeficiency conditions Liza Peikrishvili 2024 Immunodeficiency conditions - classification  Immunodeficiency conditions - classification Immunodeficiencies can also be divided into primary (usually genetic) and secondary, where the immune defect is caused by some othe...

Immunodeficiency conditions Liza Peikrishvili 2024 Immunodeficiency conditions - classification  Immunodeficiency conditions - classification Immunodeficiencies can also be divided into primary (usually genetic) and secondary, where the immune defect is caused by some other nonimmunological disease.  Immunodeficiency conditions - classification Immunodeficiencies are divided into those of the specific immune system (e.g. T cells or B cells) or those of the innate or nonspecific immune system (e.g. complement and neutrophils).  Immunodeficiency conditions - classification 1. Antibody (B cells) immunodeficiency diseases, for example, congenital, X-linked (Bruton's) agammaglobulinemia 2. Cellular (T cell) immunodeficiency diseases, for example, AIDS (helper T cell deficiency) 3. Combined antibody-mediated (B cell) and cell-mediated (T cell) immunodeficiency, for example, severe combined immunodeficiency disease Disorders of Chemotaxis 1. Wiskott-Aldrich syndrome 2. Phagocytic dysfunction diseases, for example, chronic granulomatous disease 3. Complement abnormalities in immunodeficiency diseases, for example, C3 deficiency Clinical features of immunodeficiency X-linked agammaglobulinaemia (Bruton’s disease)  This was the first immunodeficiency to be described (1952). It has an incidence of 1 in 100 000–200 000 and a prevalence of 1 in 10 000  Genetic disorder due to a mutations on the X chromosome affecting the btk gene (Bruton agammaglobulinemia tyrosine kinase) - Gene is located at Xq21.3–22  Defects in the gene prevent B-cell maturation from pro-B-cell to pre-B-cell https://www.youtube.com/watch?v=87pJDxNI-2U X-linked agammaglobulinaemia (Bruton’s disease) X-linked agammaglobulinaemia (Bruton’s disease) Presentation  Usually early in childhood, after 6 months of age, when maternal antibody has largely disappeared  Recurrent infections of lungs and ears (children of this age don’t have sinuses): Haemophilus influenzae and pneumococci (upper and lower respiratory tract, meningitis) meningococcus (meningitis) Staphylococci (septic arthritis) Giardia Salmonella Campylobacter infections of the gut Rarely Pneumocystis Milder phenotypes may present later X-linked agammaglobulinaemia (Bruton’s disease) Diagnosis  Manifested in males  Bacterial infection  B cells are low or absent  IgG ↓↓  T-cell numbers and function are normal  NK-cell numbers and function are normal X-linked agammaglobulinaemia (Bruton’s disease) - treatment  IV IgG should be started at the earliest opportunity at a dose of 200–600mg/kg/month given at intervals of 2–3 weeks Longer intervals do not give satisfactory replacement  Subcutaneous immunoglobulin given weekly (same total dose) is an alternative  Prompt antibiotic therapy (course of 10–14 days) for upper and lower respiratory tract infections  Prophylactic azithromycin 3x/week 9 carbocisteine - where there is established bronchiectasis  Long-term immunological follow-up (plus additional specialist input as required). Wiskott–Aldrich syndrome (WAS) Wiskott–Aldrich syndrome is an X-linked disorder causing thrombocytopenia with small platelets, eczema, and a progressive immune deficiency The same gene is also responsible for X-linked thrombocytopenia, a milder variant in which the eczema and immune deficiency are absent, and X-linked neutropenia Wiskott–Aldrich syndrome (WAS)  X-linked disease  The gene is located at Xp11.23 encoding WASP (Wiskott–Aldrich-associated protein) https://www.youtube.com/watch?v=R5ADKNVc6t4 Wiskott–Aldrich syndrome (WAS) Wiskott–Aldrich syndrome (WAS)  Wiskott–Aldrich syndrome (WAS) Presentation  Early childhood - in males with severe eczema, which has an atypical distribution compared with atopic eczema  Eczematous skin  Abnormal bleeding is due to the low platelet count, and bleeding  Infections develop more gradually, usually affecting the respiratory tract, and are bacterial  Opportunist infections: Pneumocystis, disseminated molluscum contagiosum, papillomavirus, systemic varicella, herpes simplex, and CMV  Fungal infections are uncommon, and are mainly Candida  Inflammatory bowel disease  Family history Wiskott–Aldrich syndrome (WAS) Wiskott–Aldrich syndrome (WAS) Wiskott–Aldrich syndrome (WAS) Diagnosis  Clinical features: there is thrombocytopenia (variable in range