Obstetrics - TORCHES Infection - HIV

Question 1

TORCHES Infections?

HIV

What is it?

Answer 1

What is HIV:

• RNA retrovirus (Lentivirus genus)
• Virus causes acquired immunodeficiency syndrome (AIDS)

Causes:

• HIV1:
  
  • Group M, subtypes A to J: Europe, North America, Australia, Sub Saharan Africa
  • Groupo O, mainly in Cameroon
• HIV2:
  
  • Confined to West Africa

Question 2

TORCHES Infections?

HIV?

Transmission?

Answer 2

Unprotected sexual intercourse

Shared needles

Contaminated blood transfusions

Vertical transmission, mother to child

Virus passes thro placenta

Also passed thro breast milk

Question 3

TORCHES Infections?

HIV?

Genes required for viral replication?

Answer 3

PEG:

P - Pol: encodes reverse transcriptase and integrase

E - Env: encodes envelops proteins (eg gp 120)

G - Gag: encodes viral structure proteins

Question 4

TORCHES Infections?

HIV?

Investigations?

Answer 4

Enzyme-linked immunosorbent assay (ELISA))

Western blot test

Immunofluorescence assay (IFA)

Nucleic acid testing

Question 5

TORCHES infections?

HIV?

Treatment?

Answer 5

Conservative:

• Patient advice
• Ceasarian delivery

Medical:

• Highly active antiretroviral therapy (HAART):
  
  • Nucleoside reverse transcriptase inhibitors (NRTIs) eg zidovudine (particulsrly reverses vertical transmission)
  • Non-nucleoside reverse transcriptase inhibitors (NNRTIs) eg nevirapine
  • Protease inhibitors (PIs) eg atazanavir
• Give either:
  
  • Two NRTIs combined with one NNRTI, or
  • Two NRTIs combined with a PI, or
  • Two NRTIs with one Intergrase Inhibitor eg raltegivir

Question 6

TORCHES infections?

HIV?

Treatment?

Special Notes?

Answer 6

• NRTs cross the placenta
• NNRTIs nevirapine/efirenz cross the placenta
• PIs do not cross the placenta easily
• Zidovudine given IV during labour

Neonatal care:

• Infant zidovudine started after delivery, contd for 6 weeks

Hepatitis B co-infections:

• tenofovir/lamivudine, or
• emtricitabine

Question 7

TORCHES infections?

HIV?

Complications?

Answer 7

Fetal:

• IUGR - Intrauterine growth restriction
• Stillbirth

Maternal:

• Pre-eclampsia
• Increased risk of infection
  
  • Toxoplasmosis
  • CMV retinitis
  • Pneumocystic jiroveci pneumonia
  • Kaposi’s sarcoma
  • Cryptococcal meningitis
  • Mycobacterium avium complex