First Aid, Chapter 8, Immunologic Disorders, Antibody Deficiencies

Question 1

When should antibody deficiencies be considered?

Answer 1

Recurrent sinopulmonary infections

Enteroviral infections (XLA)

Giardiasis

Autoimmune phenomenon

Question 2

In selective IgA deficiency, what are CD19/20, IgG, IgA, IgM levels and postimmunization levels?

Answer 2

CD 19/20 Normal

IgG Normal

IgA

Question 3

In XLA, what are CD19/20, IgG, IgA, IgM levels and postimmunization levels?

Answer 3

CD 19/20 Very low/absent

IgG

Question 4

In CVID, what are CD19/20, IgG, IgA, IgM levels and postimmunization levels?

Answer 4

CD 19/20 Normal or low

IgG

Question 5

In Hyper IgM, what are CD19/20, IgG, IgA, IgM levels and postimmunization levels?

Answer 5

CD 19/20 Normal

IgG

Question 6

What are the infections associated with transient hypogammaglobinemia of infancy (THI)?

Answer 6

Sinopulmonary GI, thrush, meningitis (usually not severe) May be asymptomatic

Question 7

What are the lab findings in transient hypogammaglobinemia of infancy?

Answer 7

IgG

Question 8

What is the therapy of transient hypogammaglobinemia of infancy?

Answer 8

Mostly no Rx, may need prophylactic antibiotics, but rarely IVIG Usually resolved by 2–4 years old

Question 9

What is the most common primary immunodeficiency disorder?

Answer 9

Selective IgA deficiency

Question 10

What is the inheritance of selective IgA deficiency?

Answer 10

Unknown Some sIgAD + CVID has TACI mutation Most common primary immunodeficie ncy disorder

Question 11

What are the infections in selective IgA deficiency?

Answer 11

Majority asymptomatic; Sinopulmonary , GI infections;

Autoimmune and atopic disease;

Rare: anti-IgA Ab -> transfusion reactions

Question 12

What are the lab findings in selective IgA deficiency?

Answer 12

IgA

Question 13

What are causes of secondary IgA deficiency?

Answer 13

Antiepileptics Sulphasalazin ecaptopril, thyroxin

Question 14

What conditions might IgA deficiency be a part of?

Answer 14

Ataxia telangectasia

IgG2 subclass deficiency

chronic mucocutaneous candidiasis

Question 15

What is the treatment for selective IgA deficiency?

Answer 15

Treatment and prophylactic antibiotics; and IVIG if concomitant specific antibody defect Monitor progression to CVID

Question 16

What are the infections and clinical findings in specific antibody deficiency?

Answer 16

Sinopulmonary infections Allergic rhinitis

Question 17

What are the lab findings in specific antibody deficiency?

Answer 17

Normal IgG, A, M Poor polysaccharide response despite pneumovax

Question 18

What age does specific antibody deficiency occur in?

Answer 18

> age 2

Question 19

What is the treatment for specific antibody deficiency?

Answer 19

Prophylactic ABx and IVIG Monitor progression to CVID

Question 20

What is the mutation of X linked aggamaglobinemia?

Answer 20

BTK (Bruton’s tyrosine kinase)

Question 21

What are the infections in XLA?

Answer 21

Sinopulmonary infections, atypical bacteria, GI infections, enteroviral encephalitis, septic arthritis, lymphoreticular and colorectal malignancies, bronchiectasis

Small/absent lymphoid tissue, no germinal cente

Question 22

What are the lab findings in XLA?

Answer 22

Low IgG, A, M (

Question 23

What stage does the maturation of B cells arrest at in XLA?

Answer 23

Maturational arrest at the pre-B lymphocyte stage

Question 24

What types of test should you avoid to test for infectious disease in XLA?

Answer 24

Do not use serologic assays to diagnose infectious diseases—ex. ELISA for HIV Use PCR assays or cultures instead

Question 25

What is the treatment for XLA?

Answer 25

IVIG treatment and ABx Rx

Question 26

What is contraindicated in XLA?

Answer 26

Live immunizations contraindicated

Question 27

What is the inheritance/mutation in autosomal recessive agamma-globulinemia?

Answer 27

Surrogate light chain (V pre-B; λ5), μ IgM heavy chain (Cμ), Igα, Igβ, BLNK

Question 28

What are the infections/clinical findings in autosomal recessive agammaglobulinemia?

Answer 28

Same as XLA Can be more severe and earlier onset than XLA (XLA - Sinopulmonary infections, atypical bacteria, GI infections, enteroviral encephalitis, septic arthritis, lymphoreticula r and colorectal malignancies, bronchiectasis Small/absent lymphoid tissue, no germinal center)

Question 29

What are the lab findings in autosomal recessive agammaglobulinemia?

Answer 29

IgG, A, M (

Question 30

What is the most common mutation in autosomal recessive agammaglobulinemia?

Answer 30

μ IgM heavy chain—most common of AR agammaglobulinemia

Question 31

What is the treatment for autosomal recessive agammaglobulinemia?

Answer 31

Same as XLA, which is: IVIG treatment and ABx Rx Live immunizations contraindicated

Question 32

What are the mutations in CVID?

Answer 32

Mostly unknown; ICOS, TACI; BAFF-R, CD19 complex, CD20

Question 33

What are the infections/clinical findings in CVID?

Answer 33

Age >2 years old, sinopulmonary, GI infections, meningitis Bronchiectasis, BOOP, autoimmune disease, GI/liver disease, granulomatous disease, nonHodgkin’s lymphoma, and gastric carcinoma

Question 34

What are the lab findings in CVID?

Answer 34

IgG (

Question 35

What is Good's syndrome?

Answer 35

CVID + thymoma

Question 36

What is associated with the noninfectious complications of CVID?

Answer 36

Reduced # of switched memory B cells shown to be associated with certain noninfectious complications (hematologic autoimmunity)

Question 37

What is the treatment for CVID?

Answer 37

IVIG treatment and ABx Rx No live vaccine Pulmonary hygiene for bronchiectasis Excise thymoma if present

Question 38

What are the infections/clinical findings in IgG subclass deficiency?

Answer 38

mostly asymptomatic

Question 39

What are the lab findings in IgG subclass deficiency?

Answer 39

Normal IgG and low level of ≥1 subclasses IgG2 deficiency can occur with SIgAD with impaired Ab response to polysaccharide

Question 40

Is IgG sublcass deficiency a true primary immunodeficiency?

Answer 40

Controversial if true PIDD—20% of population have subnormal of ≥1 subclasses (esp. IgG4)

Question 41

What is the treatment for IgG subclass deficiency?

Answer 41

Rx as SAD in case of poor polysaccharide response

Question 42

What is the inheritance/mutation in hyper IgM 2?

Answer 42

AR | AID deficiency

Question 43

What is the inheritance/mutation in hyper IgM 4?

Answer 43

AR | UNG deficiency

Question 44

What are the infections and clinical findings in hyper IgM2 and hyper IgM4?

Answer 44

Sinopulmonary and GI infections; Lymphoid hyperplasia and adenopathy CVID-like, but have increased autoimmune disease

Question 45

What are the lab findings in Hyper IgM 2 and hyper IgM 4?

Answer 45

↓IgG, IgA, IgE, and normal or ↑ IgM; Normal T-cell function ↑LN and giant germinal centers.

Question 46

What are the AID and UNG genes required for?

Answer 46

AID (activation-induced cytidine deaminase) and UNG (uracil-DNA glycosylane) are required for class switch recombination and somatic hypermutation of B cell

Question 47

Why are Hyper IgM2 and 4 less severe than Hyper IgM1, 3, and NEMO?

Answer 47

No T-cell defect -> less severe than HIGM1, 3 and NEMO defec

Question 48

What is the therapy for hyper IgM 2 and 4?

Answer 48

IVIG ABx Rx No live vaccines

Question 49

What stage of B-cell development is affected by BTK mutation?

Answer 49

Arrest in pre-B–cell stage

Question 50

What are the differences between HIGM1/3 and HIGM2/4?

Answer 50

HIGM1/3 are combined immune deficiencies with more severe/wide spectrum of infections with absent LN and germinal centers due to defects in CD40L-CD40 interactions. HIGM2/4 are antibody deficiencies with less severe infections. Lymphoid hyperplasia and adenopathy are noted. Defects are in Bcell class switching and somatic hypermutation