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Infectious Disease II, Case 0007 — HIV

Post-Exposure Prophylaxis, Sixty Hours Late

A needlestick with visible blood and an unknown source isn't the borderline case the old two-drug-versus-three-drug debate was built for — the real question tonight is whether sixty hours is still soon enough to matter.

Abbreviations, terms, and other agents mentioned in this case PEP — post-exposure prophylaxis  ·  CDC — Centers for Disease Control and Prevention  ·  HIV — human immunodeficiency virus  ·  HBV — hepatitis B virus  ·  HCV — hepatitis C virus
Presentation

L.S., a 33-year-old emergency department nurse, sustained a needlestick while drawing blood from a trauma patient during an overnight shift that, by her account, had already run two codes and a mass-casualty drill by the time it happened. She didn't report it that night — the department was short-staffed and she assumed she'd deal with it in the morning — and by the time she came to occupational health the next evening, sixty hours had passed since the stick. The needle was a hollow-bore blood-draw needle with visible blood, and the source patient, who arrived unconscious after a motor vehicle collision and remains intubated, has no HIV status on file and no family available yet to consent to testing. L.S. has no chronic illness, is not currently on any medications, and her most recent HIV test, part of a routine annual employee health screen four months ago, was negative. She has worked in this same emergency department for nine years and, by her own account, has never before delayed reporting an exposure this long — a detail she raised herself, unprompted, clearly uneasy about the gap.

Two genuinely different questions are in front of the team tonight, and it matters which one actually applies. The older PEP framework used to reserve a full three-drug regimen for higher-risk exposures and offer a simpler two-drug regimen for lower-risk ones — but a hollow-bore needle with visible blood from an unknown source was never the low-risk case that distinction was built around, so the regimen question here is less contested than the timing one. Current CDC guidance describes PEP as most effective the sooner it starts, ideally within hours, and names 72 hours as the outer window past which there's no reliable evidence of benefit and case-by-case judgment takes over. At sixty hours, she is inside that window, but close enough to its edge that the decision isn't automatic — twelve hours further and this would be a different conversation entirely, one about whether to start PEP at all rather than which regimen to use.

L.S. · 33 60 Hours Post-Exposure
Exposure
Hollow-bore needlestick, visible blood, hour 60
Source patient status
Unknown — unconscious, unable to consent to testing
L.S. baseline HIV status
Negative, tested 4 months ago
L.S. HIV test today
Negative (baseline for this exposure)
Renal function
Creatinine 0.7 mg/dL, normal
Hepatitis B status
Immune (prior vaccination)
Pregnancy status
Not pregnant
Other history
No chronic illness, no current medications

Occupational health clinic, evening of day three

Infectious Disease Physician Opening

Start standard three-drug PEP — bictegravir with tenofovir alafenamide and emtricitabine, as the single tablet. The 2013 PHS guidelines are what made three drugs the rule for every occupational exposure rather than only the ones an older framework called high-risk, and the 2025 PHS update kept that rule while replacing the raltegravir backbone many of us still have in our heads. The framework is what changed, not the exposure.

Emergency Medicine Physician Response

I'd actually go a step further on the framing — I don't think the two-drug-versus-three-drug question was ever really live for a stick like this one.

A hollow-bore needle with visible blood from a source of unknown status was always the kind of exposure that framework treated as higher-risk, even under the old stratified approach. The actual decision point tonight is the sixty hours, not the drug count. CDC names 72 hours as the outer window with no reliable evidence of benefit past it — she's inside it, but I want that named directly rather than buried under a regimen debate that isn't really in question.

Occupational Health Pharmacist Final

Agreed on both points — start three-drug PEP now, inside the window. One practical note, and I'd push back gently on how it's usually framed: the argument for the current regimen isn't that it's more potent. The 2025 PHS review found no effectiveness difference against the old raltegravir backbone. It's that raltegravir was twice daily and this is one tablet once a day, and completion rates are measurably better for the once-daily regimens. That matters here specifically because she may end up taking a full 28-day course for an exposure whose source status is still unconfirmed — the moment the urgency drops is the moment a twice-daily regimen stops getting taken.

Regimen selected
Bictegravir / Tenofovir Alafenamide / Emtricitabine
INSTI + NRTI backbone · single tablet · 28-day course
One of the two regimens named preferred in the 2025 PHS occupational-PEP guidelines (listed alphabetically, not by preference, alongside dolutegravir plus two NRTIs); started tonight given she remains inside the 72-hour window. Chosen as the single-tablet option for a 28-day course she may complete after the urgency has passed.
Raltegravir + Tenofovir DF / Emtricitabine — Superseded
Former preferred regimen
The preferred regimen under the 2013 PHS guidelines and still the one many clinicians reach for by habit; no longer among the recommended regimens after the 2025 PHS update, which cited equivalent effectiveness but better course completion with once-daily options.
Source Patient HIV/HBV/HCV Testing
Diagnostic · Pending consent
Ordered as soon as consent can be obtained; a confirmed-negative result would allow PEP to be discontinued before the full 28-day course.
Two-Drug PEP Regimen — Not Selected
Considered, not adopted
This exposure was never the lower-risk scenario the older stratified framework reserved a two-drug regimen for; current guidance favors three-drug regardless.
Where this was left

Agreed without real disagreement once the two questions were separated: three-drug PEP started tonight, at hour sixty, inside the 72-hour window. Source-patient testing will be pursued as soon as consent is available, with L.S.'s own final HIV testing scheduled at 12 weeks. Because she started PEP well beyond 24 hours after the exposure, she also meets the 2025 PHS criterion for interim testing at 4-6 weeks, which a healthcare worker who presented promptly would not.

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