July 1, 1998
Recommendations for PEP for those exposed to blood or bodily fluids of HIV patients included ZDV + 3TC for 38 providers, ZDV + 3TC + indinavir for 18, a combination of two other nucleosides and a protease inhibitor for two, and another dual nucleoside combination for 7. The number of health care providers who completed 7-, 14-, or the complete 28-day course of PEP therapy is shown in the table below.
|Number Providers Completing Therapy|
|7 Days||14 Days||21 Days||Total|
|ZDV + 3TC||6||3||25||38|
|ZDV + 3TC + IDV||2||6||8||18|
|2 other NRTIs + PI||2||2|
|2 other NRTIs||7||7|
Therapy was discontinued by the prescribing physician in two cases. One provider stopped therapy after developing liver function abnormalities 14 days after beginning PEP. This individual was diagnosed with acute hepatitis C infection. The provider was started on interferon therapy for the HCV infection. HIV serology and PCR were negative 6 months after exposure, but were both positive when tested 13 months after exposure.
Several important observations can be made from this study. First, a group of highly motivated individuals who understand that their therapy will be of limited duration cannot complete a full course of PEP. This is an important message for people who take care of HIV infected individuals -- these medications can be tough to take. Another important observation is that PEP may alter the time that an individuals develops an antibody response to HIV and the time until someone has a detectable PCR. Without PEP it was assumed that all individuals would seroconvert within six months of exposure if they were going to. Certainly, one would have anticipated that the HIV PCR would be detectable within that period of time. The individual who became infected had a negative antibody and HIV PCR six months following exposure after taking two weeks of PEP. One unanswered question in this case is whether the interferon therapy could have affected HIV replication resulting in a delay in seroconversion and viral replication that could be detected by PCR.