Primer 14

Question 1

Describe the HIV genome

Answer 1

diploid RNA; has assc reverse transcriptase

Question 2

What are the two envelope proteins assc with HIV and what are their functions?

Answer 2

gp120- grabs onto CD4+ receptors on T cells & macs; allows it to bind co-receptor (CCR5 or CXCR4)
gp41- allows fusion and entry of virus into host cells

Question 3

What cells are infected early in HIV?

Answer 3

Macs first via CCR5 co-receptor

T cells later via CXCR4 receptor

Question 4

What are the three genes assc with the HIV virus and what do they code for?

Answer 4

gag- p24 capsid protein
env- gp120/41
pol- reverse transcriptase/ integrase

Question 5

How is HIV diagnosed?

Answer 5

1st- ELISA- very sensitive, not selective (get false +)
Later- Western Blot- very specific/ selectivity (get TRUE +’s)

New test: Also, 4th gen: p24 antigen testing

Question 6

How is the effectiveness of antiviral drug therapy measured? When else is this technique useful?

Answer 6

viral load

• can also be used to confirm a diagnosis in neonates (who may have mom’s Abs but not mom’s virus)
• can pick up acute HIV infection

Question 7

When is AIDs diagnosed?

Answer 7

-CD4+

Question 8

Describe time course of HIV infection:

Answer 8

• 1-2 months asx + possible negative tests
• 2 months: flu sx (acute retroviral syndrome) for weeks
• many years of asymptomatic state
• decreasing CD4 counts/ opportunistic disease/ AIDs

Question 9

Malignancies assc with AIDs (3)

Answer 9

1. Diffuse Large B Cell lymphoma (EBV)
   * May be primary CNS; single ring enhancing lesion
2. Kapsoci’s Sarcoma (HHV 8)
   * purple spots!
3. Squamous cell carcinoma of cervix/ anus (HPV 16/18)

Question 10

Neurological infections assc with HIV (5)

Answer 10

1. cryptococcal meningitis #1
2. toxo- many ring enhancing lesions!
3. primary CNS lymphoma- single ring enhancing lesion
4. PM- reactivation JC virus
5. AIDs dementia

Question 11

Pulmonary infections assc with AIDs

Answer 11

• MAC; CD4+ below 50
• TB
• PCP; interstitial infiltrates on Xray
• histoplasma in certain regions; bird/ bat droppings

Question 12

Most common cause of retinitis in AIDS + how do you treat it? Sign on fundoscopic exam?

Answer 12

CMV

• cotton wool spots
• gancyclovir

Question 13

Owl’s eye inclusion is assc with?

Answer 13

CMV

Question 14

Cryptosporidiosis causes what in AIDs patients?

Answer 14

chronic diarrhea and wasting

Question 15

Mouth infections in AIDs

Answer 15

esophageal candidiasis- PAINFUL! (CD4

Question 16

When does prophylaxis against opportunistic infections begin for HIV patients?

Answer 16

CD4

Question 17

What are the assc pathologies for:

1. Ab’s against platelets
2. bamboo spine
3. Webbed neck, short stature
4. painful lesions on finger pads + fever
5. dry eyes and mouth + arthritis
6. posterior cervical lymphadenopathy
7. low serum ceruloplasmin

Answer 17

1. ITP
2. akylosing spondylosis
3. Turner’s syndrome
4. Osler’s nodules= endocarditis
5. Sjorgens Syndrome
6. EBV mono; otitis media
7. Wilson’s Disease

Question 18

Primary energy source during a 2 day fast

Answer 18

fatty acids

Question 19

How does a G6PD deficiency effect red cells?

Answer 19

needed to convert NADPH –> glutathione
glutathione is responsible for preventing oxidative damage of red cells; deficiency= hemolytic anemia

• G6PD is the rate limiter for the HMP shunt!