Hello Dr. Frascino!

Thank you very much for your reply! Apparently I couldn't make myself clear enough - probably because I'm not a native speaker.

With my question I didn't mean the ARS - of course I know it take a couple of weeks to develop (and I hope this diminishes your surprise as to how I got through med school). What I meant was a lymph node reaction at the ENTRY SITE, assuming I could have been contaminated through the oral mucosa. It is not uncommon that pathogens first reach the lymph nodes draining the region where they entered the body and first produce an early lymph node reaction there, before a systemic reaction appears, right? I was wondering if that were also possible with HIV - that it reaches the regional lymph nodes via lymph vessels, infects the lymph cells in those nodes a produces a slight lymph node reaction, before having replicated enough to induce an ARS. I imagine it could reach the regional lymph nodes within 24 hours after inoculation...

As to the guidelines - I live in Europe and the European guidelines (or at least the ones in use in my country) state PEP should be started within 24 hours, the sooner the better, and it is ineffectiv if started later than 72 hours after exposure. So this leaves a grey zone between 24 and 72 hours... Moreover I was wondering how steep the decline of PEP efficiency is if taken after let's say 2 hours compared with 24-25 hours, which is the recommended limit in the European guidelines. Sorry for not being acquainted with the PEP guidelines in use on other continents...

Hope to hear from you again!

Regards, Toni

Hi Toni,

Although regional lymph nodes may be the first to encounter HIV, for a number of immunologic reasons we do not see an initial isolated lymphadenopathy reaction. HIV reproduces extremely quickly and is largely unchecked by the immune system during acute disease. It rapidly disseminates widely. Recent work by a number of investigators has shown the real action (damage) is done in the gastrointestinal tract where CD4+ T-cells are dramatically and drastically depleted very early in the course of this disease.

Regarding the PEP guidelines, all guidelines stress PEP should be started as soon as possible after an exposure. If 72 hours has lapsed, PEP is no longer felt to be of benefit. There really isn't a gray zone between 24 and 72 hours. The chances of PEP aborting an infection decrease steadily with time from exposure. Certainly 24 hours is better than 72 hours, just as 12 hours is better than 24 hours. Consequently the guidelines in Europe and the U.S. are basically in concurrence.

Good luck!

Dr. Bob

How soon can infection acute symptoms appear? May 12, 2009

Hello Doc!

I started freaking out (again) - on Fri evening I had protected receptive anal intercourse with an unknown guy. After he came once he continued the intercourse without changing the condom. At some point the condom broke while he was inserting his penis and he withdrew immediately - at least that's what he said; I couldn't notice that the condom broke. So I cannot tell how large the contamination with his semen was. Anyway I rinsed the anal mucosa with cold water. The next afternoon I realised since I didn't know his HIV status and the TRUE extent of contact with his semen the whole exposure would not be as low risk as I initially thought. After doing some reading (radiologist resident here) I found out PEP is given in case of non-occupational exposures as well and would be indicated in such a case as mine. Ran to the hospital where I got the PEP, some 25 hours after the incident. Is it really crucial that PEP begins STRICTLY within 24 hours and 25 hours migght be too late already?

The whole anxiety got a lot worse when on the afternoon after exposure (before getting the PEP) a small (approx. 6-7 mm) lymph node in in front of my left ear got a bit firm and was (still is) well palpable throught the slightly reddened skin over it. Now (2 days later) another even smaller node with reddened overlying skin is palpable behind my left ear / mastoid. IS IT REALLY POSSIBLE for lymph nodes to become firm / slightly swollen within 2-3 days after an HIV infection?

For fairness only: I had some dental treatment which involved some bleeding and pain of the gums the day before the encounter.

Response from Dr. Frascino

Hi Radiology Resident,

PEP (post-exposure prophylaxis) should be started as soon as possible and no later than 72 hours after an HIV exposure. I would suggest you download a copy of the updated guidelines for PEP in both the occupational (http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5409a1.htm) and nonoccupational (www.cdc.gov/mmwr/PDF/rr/rr5402.pdf ) settings. This is information that as a physician and sexually active gay man you should be well versed in.

The symptoms associated with acute retroviral syndrome (ARS) following HIV primary infection take several weeks (not several hours or days)to become manifest. Consequently your isolated lymphadenopathy would not be related to HIV. I'm a bit surprised you made it through medical school without a better working knowledge of HIV disease. I think it's time for a refresher course. A good place to start would be with the wealth of information on this Web site, in its archives and on the related links. Have a look!

Good luck. Get informed!

Dr. Bob