Exam 3 - Immunocompromised Host

Question 1

Predisposing Factors (3)

Answer 1

1) neutropenia, decreased phagocyticity
2) defects in cellular immunity
3) defects in humoral immunity

Question 2

Neutropenia

Causes (3)

Answer 2

1) chemotx
2) bone marrow transplant
3) leukemia

Question 3

Neutropenia
Offending organisms
Gram neg rods

Answer 3

Pseudomonas, Klebsiella, E. coli

Question 4

Neutropenia
Offending organisms
Gram pos cocci

Answer 4

staph, strep

Question 5

Neutropenia
Offending organisms
fungi

Answer 5

candida, apergillus, mucor

Question 6

Cellular immunity

Causes (4)

Answer 6

1) AIDS
2) hodgkins
3) monoclonal Ab tx
4) long-term corticoid tx

Question 7

Cellular immunity
Offending Organisms
Bacteria

Answer 7

listeria, nocardia, salmonella, mycobacteria

Question 8

Cellular immunity
Offending Organisms
viruses

Answer 8

HSV, VZV, CMVV

Question 9

Cellular Immunity
Offending Organisms
fungi

Answer 9

cryptococcus, pneumocystis

Question 10

Humoral Immunity

Causes (3)

Answer 10

agammaglobulinemia, mult myeloma, splenectomy

Question 11

Humoral Immunity

Offending Organisms

Answer 11

Encapsulated Bacteria:

Strep pneum, Haem influenzae

Question 12

Neutropenia
Tx if febrile,
w/ or w/o inflamm sx

Answer 12

• empiric abx tx
• GNR coverage
• ANC reovery

Question 13

Neutropenia

Common infections

Answer 13

• septicemia/bacteremia
• oropharyngeal infx’ns (HSV, candida, bacteria)
• pulmonary infx’ns
• skin/soft tissue infx’ns (esp w/ intravasc devices)

Question 14

HIV
CD4<200
Whatcha gonna get?

Answer 14

Pneumocystis jiroveci

Question 15

HIV
CD4<100
Whatcha gonna get?

Answer 15

Cryptococcus
MAI
CMV
toxoplasma
cryptosporidium
etc.

Question 16

HIV

Oropharyngeal infx’ns (3)

Answer 16

1) oral candidiasis (dx w/ KOH smear)
2) oral leukoplakia (EBV)
3) Oral ulcers (HSV (smaller), CMV (larger), stomatitis)

Question 17

HIV
Cutaneous Infx’ns
(4 agents)

Answer 17

1) HSV (esp genital)
2) VZV recurrence, dissemination
3) molluscum (umbilicated, poxvirus)
4) B. henselae/quinatan (“angiomatosis”; raised, violaceous)

Question 18

HIV
Ocular Infx’ns
CMV retinitis

Answer 18

visual loss, floaters

exam: white exudates, hemorrhage, edema

Question 19

HIV
Pulmonary infections
Offending Oganisms

Answer 19

Strep pneum, H. influenz, S. aureus
Mycobacteria
Histoplasma, Coccidioides, Cryptococcus, Aspergillus
Pneumocystis jiroveci (PCP)

Question 20

HIV
Pulmonary Infx’ns
PCP
sx/dx

Answer 20

sx: fever, cough, dyspnea, reduced O2/CO2,
diffuse interstitial infiltrates on CXR
dx: sputum or BAL silver stain

Question 21

HIV
Pulmonary Infx’ns
Mycobacterial infx’ns (2)

Answer 21

1) TB reactivation
2) M. kansasii
Dx: sputum or BAL AFB stain/culture

Question 22

HIV
GI Infx’ns
Offending Organisms (2)

Answer 22

1) CMV
2) Cryptosporidium
3) Other: microsporidia, giardia, entamoeba hist

Question 23

HIV
GI Infx’ns
CMV sx/dx

Answer 23

entire GI!
odynophagia, diarrhea, proctitis, fever, ab pain
dx w/ endoscopy/biopsy/e- microscopy

Question 24

HIV
GI Infx’ns
Cryptosporidium Sx/Dx

Answer 24

chronic diarrhea, acalculous cholecystitis

dx: stool O&P stain

Question 25

HIV
CNS Infx’ns
Offending organisms/infx’ns

Answer 25

cryptococcus, toxoplasma, CMV,
JC virus (Progressive Multifocal Leukoencephalopathy (PML))

Question 26

HIV
CNS Infx’ns
CMV sx/dx

Answer 26

polyradiculopathy, ascending weakness, flacc paralysis

dx w/ CSF CMV PCR

Question 27

HIV
CNS Infx’ns
PML sx/dx

Answer 27

rapid progression of neuro deficits;

dx w/ CSF JCV PCR, imaging

Question 28

HIV
CNS Infx’ns
Disseminated infx’ns
MAI

Answer 28

mycobacterium avium intracellulare
Sx: fever, night sweats, wt loss, adenopathy, pancytopenia, adenitis
Dx: blood culture, node/marrow biopsy

Question 29

HIV

prophylaxis

Answer 29

PCP: CD4 <100 azithromycin
MTB: isonazid for +PPD or close contacts
S. pneum: immunization