Immunodeficiency And Autoimmune Disorders

Question 1

Developmental failure of 3rd and 4th pharyngeal pouch due to 22q11 microdeletion

Answer 1

DiGeorge Syndrome

Question 2

Clinical presentations of DiGeorge Syndrome

Answer 2

T cell deficiency (no thymus)
Hypocalcemia (no parathyroid)
Heart, great vessel, and face abnormality

Question 3

Defective cell mediated and humoral immunity

Answer 3

Severe combined immunodeficiency (SCID)

Question 4

Etiologies of SCID

Answer 4

Cytokine receptor defect - no binding to helper T cell
Adenosine deaminase deficiency - salvage pathway. Accumulation is toxic to lymphocytes
MHC class II deficiency

Question 5

Treatment for SCID

Answer 5

Sterile.isolation

Stem cell transplant - to generate normal B and T cells

Question 6

Lack of immunoglobulin due to B cell maturation disorder, naive B cells cannot be plasma cells

Answer 6

X linked agammaglobulinemia

Question 7

Mutation involved in X linked agammaglobulinemia

Answer 7

Bruton tyrosine kinase (signal molecule defect)

Question 8

Presentation of X linked agammaglobulinemia

Answer 8

Recurrrent bacterial, enterovirus, and giardia infections after 6 months when no more maternal antibodies

Question 9

Low immunoglobulin duento B cell or helper T cell defect

Answer 9

Common Variable Immunodeficiency

Question 10

Presentation of CVID

Answer 10

Increased risk for bacterial enterovirus and giardia infection late in childhood, increase risk fot autoimmune disease and lymphoma

Question 11

Most common immunoglobulin deficiency

Answer 11

IgA deficiency

Question 12

Presentation of IgA deficiency

Answer 12

Increased risk of mucosal infection, mostly viral

Question 13

Pathophysiology of Hyper IgM syndrome

Answer 13

Secondary signal for B cell maturation in the CD40 is defective, so helper t cell is not activated and no class switching is possible.

But B cells can still be activated by antigens so IgM production continues

Question 14

Presents with a triad of thrombocytopenia, eczema, and recurrent infections, due to x linked gene defect

Answer 14

Wiskott-Aldrich Syndrome

Question 15

C5 to C9 deficiency is at risk for what infection

Answer 15

Neisseria

Question 16

Complement deficiency characterized by hereditary angioedema

Answer 16

C1 inhibitor defiency (uncontrolled vasodilation)

Question 17

Mechanism of hypersensivity of SLE

Answer 17

Type II - binding of antibody to cells

Type III - antigen antibody xomplex

Question 18

Most common glomerular injury in SLE

Answer 18

Diffuse proliferative Glomerulonephritis

Question 19

Pathology of Libman Sacks endocarditis

Answer 19

Vegetations on both sides of valve from dposition of antibodies

Question 20

Most common antibodies in APAS

Answer 20

Anticardiolipin and lupus anticoagulant

Question 21

Anticardiolipin and lupus anticoagulant lead to erroneous results of which lab results

Answer 21

Anticardiolipin - false positive syphilis test

Lupus anticoagulant - falsely elevated PTT

Question 22

Autoimmune disorder which destroyes lacrimal and salivary glands causing fibrosis

Answer 22

Sjogren Syndrome

Question 23

Sjogren syndrome is what type of hypersensitivity reaction

Answer 23

Type IV

Question 24

Antibodies found in Sjogren syndrome

Answer 24

Anti ribonucleoprotein antibodies (anti SS-A and anti SS B)

Question 25

Sjogren syndrome patients are at increased risk for which malignancy

Answer 25

B cell lymphoma (unilateral enlargement of parotid)

Question 26

Autoimmune disorder with activation of fibroblasts and deposition of collagen (fibrosis)

Answer 26

Scleroderma

Question 27

Most commonly involved organ in diffuse scleroderma

Answer 27

Esophagus

Question 28

Antibodies in Scleroderma

Answer 28

Anti DNA topoisomerase I (Scl-70)

Question 29

Clinical manifestations of localized scleroderma

Answer 29

Calcinosis/anti Centromere antibodies
Raynaud phenomenon
Esophageal dysmotility
Sclerodactyly
Telangiectasias of skin

Question 30

Antibodies for mixed connective tissue disease

Answer 30

Anti U1 ribonucleoprotein