HIV Post-Exposure Prophylaxis after Occupational Exposure
A 32-year-old female nurse sustains a needlestick injury from a patient known to be HIV-positive with a viral load of 50,000 copies/mL and CD4 count of 200 cells/µL. The nurse is HIV-negative and not on pre-exposure prophylaxis. The injury involved a hollow-bore needle with visible blood. The source patient has been on antiretroviral therapy but has poor adherence. The nurse is 10 weeks pregnant. She has no allergies. Baseline labs: HIV rapid test negative, CBC normal, renal and hepatic function normal.
1. What is the recommended post-exposure prophylaxis (PEP) regimen for this nurse, considering her pregnancy?
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The nurse has a high-risk occupational exposure (hollow-bore needle, visible blood, source with high viral load). PEP should be initiated promptly, ideally within hours. Recommended regimen for adults and pregnant women is a 3-drug combination: tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) plus dolutegravir (DTG) or raltegravir (RAL). For pregnant women, DTG is considered safe and effective; however, some guidelines prefer RAL due to more data in pregnancy, but DTG is increasingly used. Alternatively, a protease inhibitor-based regimen (e.g., darunavir/ritonavir plus TDF/FTC) can be used, but DTG is preferred due to better tolerability. Because she is pregnant, avoid efavirenz? Actually EFV is acceptable but DTG is preferred. I would start TDF/FTC plus DTG 50 mg daily for 28 days. Baseline HIV testing should be repeated at 4-6 weeks, 3 months, and 6 months. She should be counseled about adherence and side effects.
2. If the source patient's HIV genotype shows resistance to integrase inhibitors, how would you adjust PEP?
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If the source virus has integrase inhibitor resistance, DTG or RAL may be less effective. In that case, a protease inhibitor-based regimen should be used: darunavir/ritonavir (DRV/r) 800/100 mg once daily plus TDF/FTC. Alternatively, if resistance to NRTIs is also present, consider adding a different agent, but typically TDF/FTC is still active unless resistance mutations are known. For pregnant women, DRV/r is considered safe. So I would switch to DRV/r + TDF/FTC for 28 days.