Primary Immunodeficiency Flashcards
what are immunodeficiency diseases
serious/fatal disorders caused by defects in one or more components of the immune system
what are primary immunodeficiency diseases
congenital diseases part of the immune system is absent or not working
aetiology of primary immunodeficiency
genetic defects polymorphisms polygenic disorders
polymorphisms
HLA variations MBL variations
polygenic disorders
IgA deficiency CVID (common variable immunodeficiency)APECED (Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy)
when would you suspect primary immunodeficiency
3/4 + infections/year unusual infections infections that are difficult to treat family history of neonatal deathlow lymphocyte count antibody deficiency
where can the defects occur
anywhere along the lymphocyte maturation pathway
what are antibody defects associated with
pyogenic bacterial infections - strep pneumonia - h influenzae - staphylcocci
what are complement defects associated with
meningitis caused by neisseria meningitis
what are T cell or macrophage defects associated with
protozoaviruses intracellular bacteria herpes reinfection
TH17 pathway defects are associated with
recurrent candida infection
genetic defect in chronic granulomatous disease
problem with neutrophils lack of NADPH oxidase reduces ability of phagocytes to produce reactive O2 species
features of chronic granulomatous disease
recurrent pneumonias
pathology of common variable immunodeficiency
B-cell disorder cause not known
features of common variable immunodeficiency
hypogammaglobulinaemia predisposes to autoimmune disorders and lymphoma
pathology of bruton’s X linked congenital agammaglobinaemia
defect in BTK gene severe block in B cell development X linked recessive
features of bruton’s x linked agammaglobulinaemia
recurrent bacterial infections
pathology of severe IgA deficiency
B-cell disorder B cell maturation defect
features of severe IgA deficiency
sinus and resp infection coeliac disease severe reactions to blood transfusion
pathology of digeorge syndrome
failure to develop 3rd and 4th pharyngeal pouches results in absent thymus defects in T and B cells
features of digeorge syndrome
congenital heart disease learding difficulties viral and fungal diseases cleft palate tetralogy of fallot
pathology of wiskott-aldrich syndrome
WASP gene defectproblems with actin skeleton T and B cell defects x-linked recessive
features of wiskott-aldrich disease
bacterial infections thrombocytopenia eczema low IgMautoimmune disorderscancer
pathology of severe combined immunodeficiency SCID
x linked defect in common gamma chain needed to produce many ILs defect in T and B cells
features of SCID
recurrent bacterial, viral, fungal infections FH of neonatal death low lymphocyte count
treatment for SCID
avoid live vaccines prophylaxis against opportune infections stem cell transplant
general treatment of primary immunodeficiency
identify the genetic defect prevent infections - prophylactic antibiotics if severe - immunoglobulin replacement therapy
what is secondary immunodeficiency
synthesis of key immune components is suppressed or the loss of immune components increases
what can hypogammaglobulinaemia be caused by
nephrotic syndrome malnutrition phenytoin
what can T cell deficiency be caused by
AIDSciclosporin