HIV

Question 1

Human Immunodeficiency Virus

Answer 1

HIV infects and destroys cells of the immune system especially T-Helper cells that are CD4+

Question 2

HIV: Virology

Answer 2

1. Viral surface glycoprotein (gp120) binds to CD4 glycoprotein on host cell
2. Virus penetrates host cell and releases RNA
3. Reverse transcriptase converts RNA to DNA
4. DNA incorporated into host genome

Question 3

HIV diversity

Answer 3

Mutations during RNA transcription

Question 4

HIV progression influenced by

Answer 4

• Age
• HLA type
• History of seroconversion

Question 5

Chemokine receptor 5

Answer 5

• Co-factor for viral attachment
• Mutation of allele: resistance
• Single mutant: slow progression

Question 6

HIV Epidemiology

Answer 6

• Sexual transmission
• IVDU
• Blood products
• Vertical transmission
• Organ transplant
• Needle-stick injury

Question 7

Symptoms of HIV

Answer 7

• Weight loss
• Lymphadenopathy
• Thrush
• Skin/oral disease

Question 8

Primary HIV/seroconversion symptoms

Answer 8

Similar to EDV

• Flu-like
• Fever
• Malaise/lethargy
• Pharyngitis
• Lymphadenopathy
• Toxic exanthema (rash)
• Diarrhoea, meningitis, neuropathy

Question 9

HIV Skin manifestations

Answer 9

• Seborrhoeic dermatitis
• Molluscum contagiosum
• Shingles
• Recurrent varicella zoster
• Recurrent genital, peranal, oral herpes

Question 10

HIV Mouth manifestations

Answer 10

• Oral hairy leukoplakia

- Oral candidiasis

Question 11

HIV Tumours

Answer 11

• Kaposi’s sarcoma

- B-cell lymphoma

Question 12

HIV Clinical Staging

Answer 12

1. Asymptomatic, normal activity, persistent lymphadenopathy
2. Symptomatic, normal activity, weight loss (<10%), skin changes, URTI
3. Bedridden <50%/day
4. Bedridden >50%/day

Question 13

HIV Primary Infection Investigations

Answer 13

• Acute phase serum

- Convalescent phase serum

Question 14

HIV Investigations

Answer 14

• CD4 lymphocyte

- HIV viral load

Question 15

CD4 lymphocyte

Answer 15

Normal = 500-1500 cells/mm3
Symptomatic <200 cells/mm3
- Measures disease progression

Question 16

HIV viral load

Answer 16

• Quantification: PCR assay (RNA copies/ml blood)

- Measures ART effect

Question 17

HIV Resistance (to ART) testing

Answer 17

• Specific nucleic acid mutations

- Optimal therapy

Question 18

HIV Management

Answer 18

Lifelong antiretroviral therapy

• <350 cells/mm3
• Different classes inhibit different stages
• Combination: 3 drugs, 2 groups
• Side effects: metabolic, lipodystrophy

Question 19

Reverse transcription inhibitors

Answer 19

Inhibit viral RNA conversion to DNA

Nucleoside: marrow toxicity, neuropathy, lipodystrophy

Non-nucleoside: rashes, hypersensitivity, interactions, psychiatric

Question 20

Integrase inhibitor

Answer 20

• Prevent integration into host genome

- Side effects: rashes, disturbed sleep

Question 21

Protease inhibitor

Answer 21

• Prevent maturation of virus

- Side effects: interactions, diarrhoea, lipodystrophy, hyperlipidaemia

Question 22

Fusion inhibitor

Answer 22

Block attachment (GP41)

Question 23

CCR-5 receptor antagonists

Answer 23

Prevent viral attachment

Question 24

Prevention of HIV

Answer 24

• Behaviour change and condoms
• Circumcision
• Treatment as prevention
• Pre-exposure prophylaxis
• Post-exposure prophylaxis for sexual exposure

Question 25

Needlestick injury: transmittable infections

Answer 25

• HIV
• Hep B
• Hep C

Question 26

Needlestick injury: recommended procedure

Answer 26

1. Wash off splashes on skin, eyes, nose, mouth
2. Encourage bleeding
3. Assessment of risk
   - HIV: combination ART
   - Hep B: vaccine
   - Hep C: no vaccine, immunoglobulin, ART for post-exposure
4. Report incidence