Infectious Disease

Question 1

What are the four H’s of HIV patient populations?

Answer 1

• Homosexuals
• Hemophiliacs
• Haitians
• Heroin addicts

Question 2

How is HIV measured now?

Answer 2

• HIV RNA is the main method
• 90% of people will have detectable HIV Ab 1 month after exposure (ELISA)–very sensitive but has some false positives (if positive, it’s always repeated before next step)
• Western blot if ELISA is positive

Question 3

What is the the general rule for acute HIV infection?

Answer 3

10 signs and symptoms in 24 hours

Question 4

What is the best marker for following HIV progression?

Answer 4

• Serial CD4 counts

* Viral loads (measures RNA)

Question 5

What conditions are associated with HIV+ CD4 > 500?

Answer 5

• Asymptomatic

* Increased bacterial infections, shingles, TB

Question 6

What conditions are associated with HIV+ CD4 200-500?

Answer 6

• Adenopathy
• Thrush
• Kaposi’s

Question 7

What conditions are associated with HIV+ CD4 <200?

Answer 7

• PCP
• Toxoplasmosis
• Cryptococcus

Question 8

What conditions are associated with HIV+ CD4 <50?

Answer 8

• CMV (in eyes)
• Mycobacterium avium
• ↑ risk lymphoma

Question 9

What are the main classes of HIV drugs?

Answer 9

• Reverse transcriptase inhibitors (can’t make DNA)
• Fusion/entry inhibitors (block entry into WBCs)
• Protease inhibitors (stops cleaving of HIV proteins after transcription)
• Integrase (can’t insert DNA–newest group of drugs)

Question 10

Example of integrase inhibitor?

Answer 10

Raltegravir

Question 11

Example of fusion inhibitor?

Answer 11

Enfuvirtide

Question 12

Example of CCR5 antagonist?

Answer 12

Maravioc

Question 13

What are some complications of HIV treatment?

Answer 13

• Lipodystrophy
• Lactic acidosis
• Osteopenia and porosis
• Avascular necrosis of hip
• Peripheral neuropathy

Question 14

What type of vaccines should be given with care in HIV patients?

Answer 14

Live vaccines. Seem to be more effective if given earlier in disease course.

Question 15

PCP symptoms?

Answer 15

• Gradual onset fever, dry cough, dyspnea

* CXR normal in 50% of PTs

Question 16

How do you diagnose PCP?

Answer 16

• Immunofluorescent antibody staining

* Sputum or bronchoscopy

Question 17

Best treatment for PCP (Meyers)?

Answer 17

Bactrim or a few other agents

Question 18

What is a side effect of bactrim use in HIV PTs?

Answer 18

Increased incidence of rash

Question 19

PCP prophylaxis in HIV PTs?

Answer 19

Use daily bactrim in PTs with CD4 < 200

Question 20

Cryptococcal meningitis in HIV patients?

Answer 20

• C. neoformans
• Subacute meningitis (looks different in HIV PTs)
• Often few symptoms with ↑ ICP
• Huge amounts of fungus in CSF
• Diagnose Ag in serum and CSF

Question 21

How do you treat cryptococcal meningitis?

Answer 21

• AmphoB and flucytosine

* Manage ↑ ICP

Question 22

Symptoms of CMV in HIV patients (typically in PTs below CD4 < 50)

Answer 22

• End organ manifestation
• Retinitis (most common)
• Colitis
• Esophagitis
• Neurological disease

Question 23

How does TB differ in AIDS patients?

Answer 23

• Not typical cavitary lesions (don’t have the immune system)
• Extra pulmonary manifestations more common
• More diffuse pattern in the lungs

Question 24

How does MAC (myco avium) present in HIV patients?

Answer 24

• Fever, sweats, diarrhea, hepatosplenomegaly
• Dx with blood culture
• Treat with azithromycin and prophylaxis < 50

Question 25

What kind of lesion is found in HIV PTs with toxoplasmosis encephalitis?

Answer 25

Ring-enhancing lesions (looks just like primary CNS lymphoma)

Question 26

What PML?

Answer 26

• Progressive multifocal leuko encephalopathy (from BK virus)
• No cure
• Just have progressive neurological symptoms
• No good treatment