Immunodeficiencies

Question 1

Th1 cells fail to produce IFN-gamma –> inability of neutrophils to respond to chemotactic stimuli

Answer 1

Hyper-IgE Syndrome (Job’s Syndrome)

- Finding is increased IgE

Question 2

Defective IL-2 (most common, X-linked), or Adenosine Deaminase Deficiency leads to decreased T-cell recombinant excision circles (TRECs), absence of thymic shadow/germinal centers/T-cells

Answer 2

Severed Combined Immunodeficiency (SCID)

Question 3

Findings include decreased IgA with normal IgG, IgM, and IgG vaccine titers with False-positive Beta-HCG due to presence of heterophile antibody

Answer 3

Selectie IgA Deficiency

Question 4

Defect in LFA-1 Integrin (CD18) protein on phagocytes found with neutrophilia

Answer 4

Leukocyte adhesion deficiency (type I)

Question 5

Most Common Primary Immunodeficiency that is typically asymptomatic but can have Anaphylaxis to IgA-containing blood products

Answer 5

Selective IgA Deficiency

Question 6

Defect in B-cell Maturation that can be acquired in 20s-30s with increased risk of autoimmune disease, lymphoma, and sinopulmonary infections

Answer 6

Common Variable Immunodeficiency (CVID)

Question 8

Findings include absent thymic shadow on CXR, decreased T cells, decreased PTH, and decreased Ca 2+

Answer 8

Thymic Aplasia (DiGeorge Syndrome)

Question 9

Decreased Th1 response present with disseminated mycobacterial infections and decreased IFN-gamma

Answer 9

IL-12 Receptor Deficiency

Question 10

Presentation includes FATED: coarse Facies, cold (non inflamed), staphylococcal Abscesses, retained primary Teeth, increased IgE, Dermatologic problems (eczema)

Answer 10

Hyper-IgE Syndrome (Job’s Syndrome)

Question 11

T-cell Dysfunction that presents with Candida Albicans infections of skin and mucous membranes

Answer 11

Chronic Mucocutaneous Candidiasis

Question 12

Presents with Failure to Thrive, chronic diarrhea (diaper rash), thrush, recurrent viral/bacterial/fungal infection, absence of thymic shadow/germinal centers/B cells

Answer 12

Severe Combined Immunodeficiency (SCID)

Question 13

Findings are Normal Pro-B, Decreased Maturation, Decreased # of B cells, Decreased Immunoglobulins of all classes

Answer 13

• X-linked (Bruton’s) Agammaglobulinemia

Question 14

Presents with Recurrent pyogenic infections by staph and strep; partial albinism, and peripheral neuropathy

Answer 14

Chediak-Higashi Syndrome

Question 15

Defects in the ATM gene which codes for DNA repair enzymes and increases AFP

Answer 15

Ataxia-Telangiectasia

Question 16

• X-linked recessive Defect in BTK, a tyrosine kinase gene that presents with recurrent bacterial, enterovirus (polio and coxsackievirus) and Giardia Lamblia infections after six months.

Answer 16

• X-Linked (Bruton’s) Agammaglobulinemia

- leads to NO B cell maturation

Question 16

Presents with Cerebellar Defects (ataxia), spider angiomas (telangiectasia), and IgA deficiency

Answer 16

Ataxia-Telangiectasia

Question 17

CD40 Ligand Defect on helper T cells –> inability to class switch

Answer 17

Hyper-IgM Syndrome

Question 19

X-linked defect in WAS gene on X chromosome –> T cells unable to reorganize actin cytoskeleton

Answer 19

Wiskott-Aldrich Syndrome

Question 20

Presents with Thombocytopenic Purpura, Infections, Eczema

Answer 20

Wiskott-Aldrich Syndrome

Question 21

Presents with recurrent bacterial infections, absent pus formation, and delayed umbilical cord separation

Answer 21

Leukocyte adhesion deficiency (type I)

Question 22

Lack of NADPH oxidase –> decreased ROS (superoxide) and absent resp burst in neutrophils presents with increased susceptibility to catalase-pos organisms (S. aureus, E.coli, and Aspergillus)

Answer 22

Chronic Granulomatous Disease

Question 23

Autosomal recessive defect in lysosoal trafficking regulator gene (LYST) –> microtubule dysfunction in phagosome-lysosome fusion found with Giant Granules in Neutrophils

Answer 23

Chediak-Higashi Syndrome

Question 24

Test for Chronic Granulomatous Disease

Answer 24

Abnormal Dihydrorhodamine (DHR) flow cytometry test
- Nitroblue tetrazolium dye reduction test no longer preferred.

Question 25

Findings include Increased IgE and IgA with decreased IgM, Thrombocytopenia

Answer 25

Wiskott-Alrich Syndrome

Question 26

22q11 Deletion; Failure to develop 3rd and 4th pharyngeal pouches that presents with Tetany (hypocalcemia), recurrent viral/fungal infections, congenital heart and great vessel defects

Answer 26

Thymic Aplasia (DiGeorge Syndrome

Question 26

Findings include Increased IgM with decreased IgG, IgA, and IgE and presents with severe pyogenic infections early in life

Answer 26

Hyper-IgM Syndrome