HIV post-exposure prophylaxis

Background

• Probability of HIV transmission from a percutaneous needle stick is approximately 0.3% (1 in 300) and 0.09% from mucous membrane exposure.
• Also known as HIV Post-Exposure Prophylaxis (PEP)
• ~79% transmission reduction
• Initiate ASAP (goal = <2 hours after exposure)
• >36 hours: normally deferred, unless particularly high risk
• Common side-effects = constitutional, gastrointestinal

National Clinician's Post-Exposure Prophylaxis Hotline

• 1-888-448-4911, call for expert advice

Exposure Transmission Risk

Exposure^	Risk
Percutaneous	0.3%
Mucocutaneous	0.09%
Needle-sharing injection drug	0.7%
Receptive anal intercourse	0.5%
Receptive penile-vaginal intercourse	0.1%
Insertive anal intercourse	0.07%
Insertive penile-vaginal intercourse	0.05%
Receptive oral (male) intercourse	0.01%
Insertive oral (male) intercourse	0.005%

^assumes no condom use

High Risk Exposures

Source

1. Symptomatic HIV/AIDS
2. Acute seroconversion
3. High viral load

Exposure

1. Deep injuries
2. Visible blood on device
3. Injuries sustained placing a catheter in a vein/artery

Low Risk Exposures

• Dried blood on an old needle
• Human Bites

Workup (Before Giving)

• CBC
• C7
• LFTs
• Pregnancy test

Management

Percutaneous Injuries

Superficial wound or solid needle

• If HIV+ source asymptomatic or if viral load <15000 RNA/mL give basic regimen
• If HIV+ with AIDS, acute seroconversion or high viral load give expanded regimen
• If HIV status unknown then no PEP (consider PEP if possible HIV risk from source)

Deep wound or hollow needle

• If HIV+ source asymptomatic or if viral load <15000 RNA/mL give expanded regimen
• If HIV+ with AIDS, acute seroconversion or high viral load give expanded regimen
• If HIV status unknown then no PEP (consider PEP if possible HIV risk from source)

Mucous Membrane Exposure

Small volume (few drops)

• If HIV+ source asymptomatic or if viral load <15000 RNA/mL consider basic regimen
• If HIV+ with AIDS, acute seroconversion or high viral load give basic regimen
• If HIV status unknown then no PEP (consider PEP if possible HIV risk from source)

Large volume (splash)

• If HIV+ source asymptomatic or if viral load <15000 RNA/mL give basic regimen
• If HIV+ with AIDS, acute seroconversion or high viral load give expanded regimen
• If HIV status unknown then no PEP (consider PEP if possible HIV risk from source)

Treatment Regimens

2 drug Basic

• Tenofovir-Emtricitabine (Truvada) one tablet (300 mg of tenofovir with 200 mg of emtricitabine) once daily OR
• Zidovudine–lamivudine (Combivir) one tablet (300 mg of zidovudine with 150 mg of lamivudine) twice daily
  • this regimen is preferred in pregancy

3 drug Expanded

• Ritonavir–lopinavir (Kaletra) PLUS either tenofovir–emtricitabine or zidovudine–lamivudine)
  • Two tablets (50 mg of ritonavir with 200 mg of lopinavir per tablet) twice daily, or four tablets once daily
• Ritonavir plus atazanavir (plus either tenofovir–emtricitabine or zidovudine–lamivudine
  • 100 mg of ritonavir plus 300 mg of atazanavir once daily
• Ritonavir plus darunavir (plus either tenofovir–emtricitabine or zidovudine–lamivudine)
  • 100 mg of ritonavir plus two tablets, each containing 400 mg of darunavir, once daily

CDC recommendations

From 2013 recommendations

1. PEP is recommended when occupational exposures to HIV occur
2. HIV status of the exposure source patient should be determined, if possible, to guide need for HIV PEP
3. PEP medication regimens should be started as soon as possible after occupational exposure to HIV, and continued for a 4-week duration
4. New recommendation - PEP medication regimens should contain 3 (or more) antiretroviral drugs for all occupational exposures to HIV
5. Expert consultation is recommended for any occupational exposures to HIV a
6. Close follow-up for exposed personnel should be provided that includes
   1. Counseling
   2. Baseline and follow-up HIV testing
   3. Monitoring for drug toxicity
   4. Follow-up appointments should begin within 72 hours of an HIV exposure
7. New recommendation - if a newer fourth-generation combination HIV p24 antigen-HIV antibody test is utilized for follow-up HIV testing of exposed HCP, HIV testing may be concluded 4 months after exposure; if a newer testing platform is not available, follow-up HIV testing is typically concluded 6 months after an HIV exposure.

Negligible Risk

• NOT recommended

Substantial Risk

• CDC preferred regimen for 28 days:^
  • Raltegravir (isentress) 400mg PO twice daily, plus
  • Truvada (tenofovir 300mg + emtricitabine 200mg) 1 PO once daily
• If known source patient with resistant HIV strain, consult HIV service for source-patient-specific PEP

^Consider interactions with current medication interactions and contraindications, such as renal impairment with Truvada

Pregnant Patients

• Same as above

See Also

• Occupational exposure
• Sexual assault
• Hepatitis B
• HIV testing (in California)

References

Authors

Ross Donaldson