Infections in the Immunocompromised Host

Question 1

Answer 1

Question 2

most common type of immune system deficiency

Answer 2

antibody deficiency

Question 3

Question 4

cellular components of the innate system

Answer 4

phagocytes: neutrophils and macrophages.
- migrate to side of infection
- phagocytose bacteira
- present antigens to T cells.

APCs’ antigen presenting cells.

Question 5

phagocytic defects

Answer 5

phagocytic immunodeficinecies

= chronic granulomatous disease

• leukocyte adhesino deficiency.
• predispose individuals to recurring staph auereus, nocardia, or aspergillus infections (catalase positive organisms)

Question 6

people with phagocytic defects like CGD predispose individuals to recurring staph auereus, nocardia, or aspergillus infections (__ ___ organisms)

Answer 6

catalase positive

Question 7

people with complement defs are predisposed to ___ and ___ infections

Answer 7

strep pyogenic or neisseria infeections. complement deficiencies predospose to BACTERIAL infections– no recurrent viral (T or NK ) or fungal (T/B or PMN) ENCAPSULATED BACTERIA

(YSBHNC)

Question 9

humoral B cell deficiencies often present with ____ infections

Answer 9

sinopulmonary or bacterial infections (frequent pneumonia).

• often encapsulated organisms like strep pneumo, Haemophilus, giardia/campylobacter.

Question 10

CD4 - Helper T Cells (___/__ -
__ pathogens)

CD8 - Killer T Cells (__/__
Pathogens)

Answer 10

CD4 - Helper T Cells (Bacterial/Fungal -
Extracellular pathogens)

• CD8 - Killer T Cells (Viral/Intracellular
Pathogens)

Question 11

CD4 cells interact with the innate immune system through ____ which bind MHC___ complexes. they also release ___ and recruit other immune cells. Involved in class switching from B cell Ig__ to Ig___

Answer 11

CD4 cells interact with the innate immune system through APCS which bind MHCII complexes. they also release CYTOKINES and recruit other immune cells. Involved in class switching from B cell IgM to IgG

Question 12

CD8 cells interact with MHC ___ to direct cell apoptosis lysis

Answer 12

MHCI

Question 13

PJP. Cryptococcal meningitis, oral candida, recurrent HSV are all ___pathogens which indicate ___ deficiency

Answer 13

opportunistic infection pathogens which indicate T cell deficiency (HIV, SCID)

• less CD4 cells= less cytokine production, then prevens B cell imunoglobulin class switching

Question 14

Question 15

tf in an immunocompromised host, the treatment for an infection is often empiric

Answer 15

true. gotta start the therapy early (sometimes even as prophylaxis) and then often they have overlapping infections that require different antibiotic classes.

Question 16

why is it often to make a specific diagnosis for the type of pathogen infection in an immunocompromised host

Answer 16

becauase biopsy is often contraindicated– too invasive and can introduce even more infection

Question 17

52F on prednisone (steroid) 60mg for treatment of Idiopathic Thrombocytopenia Purpura (ITP)

What component of the immune
system is targeted?

Answer 17

prednisone targets all arms of the innate and adaptive immune system– neutrophil, b cells, t cells.

• at risk for nocardia/encapsulated bacteria, strep pneumo, PJP, candida,

Question 18

46F who has just undergone Induction Chemotherapy (R-CHOP) for Diffuse Large B-Cell Lymphoma

Are they at risk of Infections? Why?

Answer 18

B cell deficiency– antibiody deficiency. Encapsulated (bcell deficiency) organism susceptible

• strep speciis

staph A

haemophilus influenza

• neisseria
• klebisella

pseudomonas

SHOULD HAVE SEPTA AND ACYCLOVIR PROPHYLAZIS

Question 19

Answer 19