Week 4 Conditions

Question 1

What deficiency results in severe recurrent pyogenic sinus and respiratory tract infections

Answer 1

Early complement deficiency (C1-C4)

Question 2

What deficiency causes increased susceptibility to recurrent Neisseria bacteremia

Answer 2

Terminal complement deficiencies (C5-C9)

Question 3

Causes hereditary angioedema because of unregulated kallikrein activation leading to increased bradykinin. Low C4 levels shown. ACE inhibitors contraindicated

Answer 3

C1 esterase inhibitor (C1-INH) deficiency

Question 4

Complement mediated intravascular hemolysis and dark urine because of lack of PIGA gene, preventing formation of GPI anchors for complement inhibitors on cell membrane. So increased complement

Answer 4

Paroxysmal nocturnal hemoglobinuria

Question 5

Recurrent bacterial and enteroviral infections after 6 months. Absent B cells in blood, absent Ig of all classes, absent//scanty lymph nodes and tonsils. Live vaccines contraindicated

Answer 5

X-linked (Bruton) agammaglobulinemia. Defect in BTK, a tyrosine kinase gene that stimulates B cell maturation.

Question 6

Mostly asymptomatic immunodeficiency. Low IgA with normal IgG and IgM. Increased susceptibility to giardiasis. Can see airway and GI infections. Anaphylaxis to IgA in blood products

Answer 6

Selective IgA deficiency

Question 7

Decreased plasma cells, decreased IgG and IgA and/or IgM. Recurrent respiratory infections, autoimmune diseases and lymphoma

Answer 7

Common variable immunodeficiency - problem with B cells differentiation

Question 8

Low T cells, absent thymic shadow, recurrent infections, facial and cardiac abnormalities, hypocalcemia (absent parathyroid glands)

Answer 8

DiGeorge syndrome, 22q 11.2 deletion

Question 9

Low Ig levels except for IgM. Pyogenic infections and opportunistic infections

Answer 9

Hyper IgM syndrome. Mutation of CD40L on Th cells, preventing class switching. X-linked

Question 10

Disseminated salmonella, fungal, and mycobacterial infections. Decreased interferon gamma.

Answer 10

Il-12 deficiency. Leads to low Th1 response

Question 11

Recurrent pyogenic infections, eczema, bruising, IgE high, abnormal WASP gene leading to decreased T cells and platelets

Answer 11

Wiskott Aldrich syndrome (eczema-thrombocytopenia-immunodeficiency syndrome)

Question 12

Increased susceptibility to catalase positive organisms. Recurrent infections and granulomas. Decreased respiratory burst in neutrophils. X linked

Answer 12

Chronic granulomatous disease. Defect in NADPH oxidase, less ROS

Question 13

PLAIN: Progressive neurodegeneration, lymphohistiocytosis, albinism, recurrent pyogenic infections, peripheral neuropathy. Giant granules in granulocytes and platelets

Answer 13

Chediak Higashi syndrome. Defect in lysosomal trafficking gene: microtubule dysfunction in phagolysosome fusion

Question 14

Failure to thrive, chronic diarrhea and thrush, recurrent infections, low TRECS, absent thymic shadow and germinal centers and T cells.

Answer 14

Severe combined immunodeficiency syndrome (SCID). Several types, most common is x linked IL-2R gamma chain defective