Immunodeficiency

Question 1

recurrent infections

Answer 1

-normal
-6 per year
-9 for daycare
12 second hand smoke
-cold 4-12 days

Question 2

when should immune eval be considered?

Answer 2

• two or more invasive bacterial infections
• persistant or recurrent sinopulmonary infections
• unusual etiologic agents or unusual severity of common infection

Question 3

evaluation for immundeficiency

Answer 3

-history
physical exam
labs

Question 4

history

Answer 4

growth and development
types and sites of infections
severity of infections, complications
specific organisms
hiv risk factors
diarrhea, malabsorption
ai or allergic phenomenon
family history

Question 5

physical exam

Answer 5

physical and anatomic barriers
growth and development
tonsils, nodes, liver, spleen
thrush
eczyma, seborrhea, petechiae, others

Question 6

nonimmunologic lines of defense

Answer 6

• skin and mucous membranes-eczyma, burns, open fractures, sinus tracts
• adequate drainage- eustachian tube dysfunction, ciliary immotility, CF, ureteral reflux
• foreign bodies-medical/accidental

Question 7

four limbs of the immune system

Answer 7

• cellular-T, NK, cytokines
• Humoral- B, Ig
• complement
• phagocytes

Question 8

distribution of primary immnodeficiencies

Answer 8

cellular 7%
complement 2%
phagocyte 20%
combined 25%
humoral 46%- IgA

Question 9

SCID

Answer 9

• FTT, thrush, skin rash, diarrhea
• male 75%
• x linked and AR
• early death without bone marrow transplant
• no t cells/ b cells
• common IL2 gamma chain defect- which is present in a lot of cell types
• adenosine deaminase deficiency
• purine nt phosphorylase deficiency
• T cell signal transduction defects
• others

Question 10

common gamma chain

Answer 10

• b cell maturation
• NK development
• hematopoeisis
• t cell development
• class switch recombination
• peripheral t cell homeostasis

Question 11

SCIDs 2

Answer 11

• CBC-lymphopenia
• enumeration of specific lymphocytes subsets assists in diagnosis
• analysis of lymphocyte proliferation in response to mitogens (stim T and B), non self HLA, specific antigens
• most need bone marrow transplant
• invasive, life threatening viral, fungal, bacterial infections
• thrush is common
• aggressive treatment with antibiotics, replacement Ig, often antivirals and antifungals while awaiting transplant

Question 12

humoral immunodeficiency

Answer 12

• bronchiectasis, recurrent sinusitis
• R/O CF, immotile cilia syndrome and HIV
• B cell enumeration (CD19 and/or 20)
• quantitative Ig- A, G, M, G subclasses, pre and post vaccine titers, isohemmagglutinins
• infectious risks-encapsulated bacteria, pneumococcus
• susceptibility to chronic enterovirus meningoencephalitis
• AI disease common
• lifelong risk of lymphoma
• common variable immunodeficiency
• selective defect in anti-polysaccharide antibody production

Question 13

x linked agammaglobulinemia

Answer 13

-absence of b cells due to mutation in brutons tyrosine kinase

Question 14

cd40 L deficiency

Answer 14

• hypogammaglobulinemia with hyper IgM- can’t react with TH2 to class switch
• no germinal centers
• no TH1 to macrophage-intracellular pathogens

Question 15

humoral immunodeficiency management

Answer 15

• Ig replacement
• early id and treatment of infections, including enteroviral disease
• aggressive pulmonary F/U

Question 16

selective IgA deficiency

Answer 16

• 1/600
• 2/3 asymptomatic
• IgG subclass 2 deficiency
• recurrent sinopulmonary infections
• defect in producing antibodies to polysaccharide antigens

Question 17

complement deficiency

Answer 17

• meningococcus
• c8 deficiency
• prompt evaluation of any febrile illness
• meningococcal vaccine and antibiotic prophylaxis

Question 18

phagocyte deficiency

Answer 18

• make them, just no oxidative burst
• liver abscess, pulmonary aspergillosis
• chronic granulomatous disease- CBC normal
• need to assay neutrophil function
• NBT
• catalse positive bacteria-staph
• fungal infections
• antibiotic prophylaxis, early id and treatment of infections
• IFN gamma

Question 19

DiGeorge Syndrome-cellular immunodeficiency

Answer 19

• cyanotic congenital heart disease
• hypocalcemic tetany
• abnormal embryonic development of 3rd and 4th pharyngeal pouched
• thymic hypoplasia/aplasia
• variable T cell numbers and funvtion
• congenital heart disease- LV outflow tract
• hypoparathyroidism
• invasive and severe viral and fungal disease
• fetal transplants of thymus
• irradiated blood products so no GVHD
• many patients have gradual improvement over time
• tetanus fine, no MMR

Question 20

HIV/AIDS

Answer 20

• loss of CD4 cells
• opportunistic infections
• kaposis, lymphoma, squamous cell carcinoma
• bacterial-TB, Mycco Avian Complex
• fungal-PCP, candida, cryptococcosis, penicillinosis
• protozoal-toxoplasmosis, microsporidiosis, crypto, isopsoriasis, leishmaniasis
• viral-CMV, HSV, VZV