Microbiology - Infections in the immunocompromised host

Question 1

Factors that can increase number of infections in kids

Answer 1

Day care and smoking exposure

Question 2

Opportunist infections in kids

Answer 2

Pneumocystis jirovecii,cryptococcus neoformans, fungal infections(besides tinea and thrush)

Question 3

Types of immunodeficiency

Answer 3

Primary - genetic defect

Secondary - acquired, anatomic or iatrogenic

Question 4

Features of primary immunodeficiency

Answer 4

occurs in first few weeks of life,therapy response is slow,infection suppressed and not eradicated, common organism cause recurrent infections

Question 5

Features of primary immunodeficiency

Answer 5

growth delay, multiple infections, unusual organisms causing dx,

Question 6

Indications for immune evaluation

Answer 6

recurrent opportunistic infection, failure to thrive, persistent infection, history of recurrent infections with a defined cause

Question 7

Most common immunodeficiency in kids

Answer 7

IgA deficiency

Question 8

Immunodeficiency presenting in early teens

2-20

Answer 8

CVID

Question 9

Recurrent aspergillus infection

Answer 9

neutrophil deficiency

Question 10

Defect in phagocyte numbers ( Kostmann congenital neutropenia)

Answer 10

No neutrophils ( Kostmann congenital neutropenia), cyclic neutropenia, recurent Aspergillus infections

Question 11

Defects in phagocyte function

Answer 11

intracellular killing, trafficking or adhesion. Features are S. aureus, Candida

Question 12

Increase numbers of Candida only

Answer 12

Myeloperoxidase deficiency

Question 13

Recurrent bacterial infections, autoimmune disorders

Answer 13

C1-C4 deficiency

Question 14

Persistent Neisseria infection

Answer 14

C5-C9 deficiency

Question 15

Immunoglobin deficiency

Answer 15

encapsulated infections( H. influenza, S. pneumoniae), Giardia

Question 16

Management of IgG and IgA deficiency

Answer 16

Give IgG for IgG deficiency, for IgA, just give prophylactic

Question 17

Severe Combined Immunodeficiency (SCID)

Answer 17

No T cells which impact B cell function. Tx with stem cell transplantation

Question 18

DiGeorge syndrome ( lymphocytic disorder)

Answer 18

Thymic hypoplasia, hypoparathyroidism, neonatal hypocalecemia

Question 19

Wiscott Aldridge syndrome lymphocytic disorder)

Answer 19

thrombocytopenia, severe eczema. Tx with stem cell transplant

Question 20

Lymphocytic disorders infections

Answer 20

Pneumocystis pneumoniae, fungal infections, protozoan infections, disseminated viral infections, recurrent bacterial

Question 21

S. aureus, Nocardia, Pseudomonas, Serratia, Candida, Aspergillus ( catalast + organisms) persistence. What defec?

Answer 21

phagocyte deficiency

Question 22

S. pneumoniae, H. influenza, Neisseria

Answer 22

Complement deficiency

Question 23

Polysaccharid organisms…S. pneumoniae, H, influenza, S. aureus, Pseudomonas, Mycoplasma, Shigella, Campylobacter, Giardia. what deficiency

Answer 23

Antibody deficiency

Question 24

Opportunisic infections - mycobacteria, S. pneumoniae, Psudomonas, Candida, Herpes virus, Adenovirus

Answer 24

Cellular and combined immunodeficiency

Question 25

Splenectomy and sickle cell disease risks

Answer 25

Increase in S. pneumoniae, H. influenza type B

encapsulated bacteria and treat with antibiotic prophylaxis

Question 26

Pregnancy ( seconday immunodeficiency)

Answer 26

UTIs, Hepatitis E, H1N1 influenza linked to increased morbidity and mortality

Question 27

Chemotherapy induced neutropenia immunodeficiency

Answer 27

Bacteria sepsis, Aspergillosis, Penumocystic pneumonia, disseminated varicella

Question 28

Workup for Possible immunodeficiency

Answer 28

History, CXR, CBC,Hgb electrophoresis, HIV, Sweat test, genomic analysis, mutation search in futue