Chapter 6: Lecture 3 (Immune Deficiencies)

Question 1

What type of infections do B cell deficiencies cause?

Answer 1

• Pyogenic bacterial infections

- Enteric bacterial and viral infections

Question 2

What type of infections do T cell deficiencies cause?

Answer 2

Viral and other intracellular microbial infections

Question 3

What type of infections do innate immune deficiencies cause?

Answer 3

Pyogenic bacterial and viral infections

Question 4

What is a Chediak Higashi syndrome?

Answer 4

Failure of phagolysosomal fusion

• foreign bacteria not destroyed
• autosomal
• fatal without stem cell transplant

Question 5

How can you detect Chediak Higashi syndrome?

Answer 5

Observe failure of phagolysosomal fusion on peripheral smear and giant granules

Question 6

What are some symptoms of Chediak Higashi syndrome?

Answer 6

• Increased bacterial infections

- Albinism or grey hair streaks

Question 7

What is chronic granulomatous disease?

Answer 7

Failure of superoxide production in phagocytes

-leads to accumulation of macrophages and granuloma formation

Question 8

What type of infections are common in a MAC deficiency?

Answer 8

Neisseria

-mostly meningitis

Question 9

What causes hereditary angioedema?

Answer 9

Deficiency of C1 inhibitor

Question 10

What are some symptoms of hereditary angioedema?

Answer 10

• Huge mucosal folds (corkscrew)
• Swelling of extremities and genitals
• Headache, dizziness
• Swelling of airway: difficulty swallowing

Question 11

What causes SCID?

Answer 11

Deficiency in both B and T cells due to T cell defects

Question 12

How does X linked and autosomal recessive SCID differ?

Answer 12

X-linked:

• mutations in IL receptors
• Reduced T cells
• B cells can’t make antibodies w/o T cells

Autosomal Recessive:

• ADA deficiency
• Accumulation of toxic purine metabolites

Question 13

What causes DiGeroge Syndrome?

Answer 13

Failure of pharyngeal pouches 3 and 4 to develop

• defect in thymus, parathyroid, heart, and great vessels
• 22q11 deletion

Question 14

What are symptoms of DiGeroge Syndrome?

Answer 14

• Facial and palatal abnormalities
• Cardiac abnormalities
• Tetany due to low calcium levels
• T cell deficiency

Question 15

What causes X-linked agammaglobulinemia?

Answer 15

Defect in BTK gene on X chromosome

-B cells can’t reach maturity

Question 16

People with X-linked agammaglobulinemia are more susceptible to what diseases?

Answer 16

Encapsulated bacteria:

• Strep pneumoniae and pyogenes
• Haemophilus influenzae type b
• Staph aureus
• Pseudomonas aeruginosa

Viruses

Protozoa: Giardia lamblia

Question 17

What causes hyper IgM syndrome?

Answer 17

Increase in IgM B cells due to lack of class switching
-T cells lack CD40L to induce switching

Question 18

People with hyper IgM syndrome are more susceptible to what diseases?

Answer 18

Encapsulated bacteria

Question 19

How is Common Variable Immunodeficiency diagnosed?

Answer 19

Disease of exclusion

• presented later
• susceptible to encapsulated bacterial infections
• recurrent sinus and pulmonary infections
• granulomas
• chronic diarrhea
• autoimmune disease

Question 20

Having an IgA deficiency makes patients more susceptible to what?

Answer 20

• Recurrent sinus and pulmonary infections
• Urinary and GI infections
• Autoimmune diseases/allergies
• Anaphylactic reaction against red cell transfusion

Question 21

What is Wiskott Aldrich Syndrome?

Answer 21

Systemic disease due to WASP gene mutation

• Thrombocytopenia: low platelets
• Eczema
• Recurrent infections (low B and T cell count)

Question 22

What is Ataxia Telangiectasia?

Answer 22

Autosomal recessive & ATM gene mutation

• Neurodegenerative disease: ataxia
• Vascular malformation: telangiectasias
• Immune deficiency in IgA and IgG