Immunodeficiencies

Question 1

Disease with NADPH deficiency.

Answer 1

Chronic Granulomatous Disease (CGD)

Question 2

Which organisms tend to infect patients with CGD?

Answer 2

Catalase (+) organisms
-NADPH oxidase generates peroxides which can be lethal to bacteria. In addition, myeloperoxidase turns hydrogen peroxide into Hypochlorite (pretty much bleach) which few microbes can survive. Without NADPH oxidase, the myeloperoxidase can only make hydrogen peroxide to fight infection, however, organisms with catalase can inhibit this defense.

Question 3

Test used to diagnose CGD.

Answer 3

Nitroblue-Tetrazolium (NBT) test.

• the WBCs are stained with NBT
• if the cells are really good at producing ROS like hydrogen peroxide, the stain will turn blue, meaning a positive NBT test. A positive NBT test means the patient does NOT have CGD.
• a negative NBT test means the patient DOES have CGD

Question 4

Which immunodeficiency results in recurrent Neisseria infections, mainly meningitis?

Answer 4

Any complement deficiency in the formation of the Membrane Attack Complex (MAC)
-includes C5, C6, C7, C8, or C9

Question 5

Which immunodeficiency results in reccurent pyogenic bacterial infections, and type III hypersensitivity reactions?

Answer 5

C3 complement deficiency.

-inability to opsonize bacteria and immune complexes

Question 6

What results from a C1 esterase inhibitor deficiency?

Answer 6

Hereditary Angioedema: the overuse of complement proteins C1, C2, and C4 results in swelling. Most noticeable in mucosal regions.

Question 7

Which immunodeficiency is associated with a TAP1 failure?

Answer 7

MHC I deficiency

• TAP1 transports peptides to the ER to be made into proteins
• CD8 cells decreased
• CD4 cells normal

Question 8

Failure of the 3rd and 4th pharyngeal pouches.

Answer 8

DiGeorge Syndrome

-no thymus, along with other congenital anomalies

Question 9

What is the condition where all Ig classes are decreased and why?

Answer 9

No Bruton Tyrosine Kinase that is needed for B cell maturation

Question 10

Problem with Hyper IgM syndrome.

Answer 10

Deficiency of CD40L receptor on T cells that is needed for Ab class switching

Question 11

Immunodeficiency associated with albinism.

Answer 11

Chediak-Higashi

Question 12

Problem in Leukocyte Adhesion Deficiency.

Answer 12

No CD18 receptors that are needed for WBCs to bind to the endothelial cells to allow extravasation.

Question 13

Pathology of Wiskott Aldrich Syndrome

Answer 13

Platelets cannot mature and are lysed in the spleen, B and T cells cannot mature and slowly decrease in number. Triad:

• eczema
• thrombocytopenia
• immunodeficiency