Physician's Weekly Article - Administering Proper Prophylaxis After HIV Exposure

       Guidelines from the CDC are available to help physicians manage both occupational and non-occupational exposures to HIV. The key message is that appropriate postexposure prophylaxis is paramount.

      Preventing exposures to blood and bodily fluids has long been considered the primary means of preventing occupationally and non-occupationally acquired HIV infection. Appropriate postexposure management is also a critical element of workplace safety for hospital settings. “Both occupational and non-occupational exposures are likely to continue to occur in the future,” says William Short, MD, “making postexposure prophylaxis [PEP] to HIV an important issue for all hospital settings.”

      The CDC recommendations on the use of PEP were updated in 2005 for both occupational and non-occupational HIV exposure largely because of the newer antiretroviral agents that have been approved by the FDA and due to additional information that has emerged regarding the use and safety of HIV PEP.

      Highlighting New Occupational Guidelines

      One of the key changes in the 2005 PEP guidelines for occupational exposures to HIV is that the list of antiretroviral medications that can be considered for use as PEP has been modified and expanded. Dr. Short says, “the CDC now emphasizes prompt management of occupational HIV exposures, the selection of tolerable HIV PEP regimens, and attention to potential drug interactions involving drugs that could be included in HIV PEP regimens and other medications [Table 1].” In addition, the CDC recommends consultation with experts for PEP management strategies, especially when determining whether an exposure has actually occurred. Use of HIV rapid testing and counseling and follow-up of exposed personnel are also paramount.

      Healthcare personnel receiving PEP are recommended to complete a full 4-week HIV PEP regimen, but Dr. Short says that many workers—as many as 50%, according to published studies—are unable to complete such a course because of issues with toxicity and side effects. “The toxicity profile of antiretroviral agents—including the frequency, severity, duration, and reversibility of side effects—is an important consideration when selecting an HIV PEP regimen,” he says. “The selection of regimens should be heavily influenced toward those that are tolerable for short-term use.” Careful evaluation of concomitant medications, including over-the-counter medications and supplements, is also needed before prescribing PEP.

      The CDC states that clinicians treating healthcare personnel will need to determine which agents and how many to use; they will also need to know when to alter a PEP regimen based on empiric decisions. Use of varying drug regimens might be justified for exposures that pose an increased risk for transmission. Two- and three-drug regimens may be viable options, depending on the exposure type. The PEP guidelines provide guidance for two- and three- (or more) drug PEP regimens on the basis of the level of risk for HIV transmission represented by the exposure. “Clinicians should review the updated guidelines before initiating PEP regimens,” Dr. Short says.

      Seeking Expert Advice

      Expert consultation may be required for occupational exposures to HIV, especially when PEP is initiated. The updated PEP guidelines provide important information on situations for which expert consultation for HIV PEP is advised, including delayed exposure reports (later than 24 to 36 hours), unknown sources of HIV (eg, needles in sharps disposal containers or laundry), and known or suspected pregnancy in the exposed person. Other situations may include resistance of the source virus to antiretroviral agents and toxicity of the initial PEP regimen.

      “The use of PEP should be decided on a case-by-case basis, considering the severity of the exposure and the epidemiologic likelihood of HIV exposure,” says Dr. Short. “Follow-up of exposed healthcare personnel—including postexposure testing and monitoring of PEP toxicity—are also important [Table 2]. Those with occupational exposures to HIV should receive follow-up counseling, postexposure testing, and medical evaluations regardless of whether they receive PEP. After initial baseline testing, when the exposure is suspected, follow-up tests should be performed at 6 weeks, 3 months, and 6 months after exposure. When workers are exposed to HIV, it’s imperative to advise them of the importance of completing the prescribed regimen.”

      Analyzing Non-Occupational Exposures

      In 2005, the CDC also released an updated version of PEP for non-occupational exposures to HIV. Data from new clinical investigations have indicated that PEP might help reduce the risk for HIV infection after non-occupational exposures. “It’s important to note that many clinicians are unaware that there are guidelines for non-occupational exposures too,” says Dr. Short. “Many of the principles that apply to occupational PEP also apply to non-occupational PEP. We want to learn from our experiences with healthcare workers who have taken PEP after occupational HIV exposures and then apply those lessons to non-occupational exposures. “To effectively deliver non-occupational PEP after HIV exposures, the CDC recommends that patients be promptly evaluated to determine the viral status of the potentially exposed person. “Instituting antiretroviral regimens within a certain timeframe—usually hours, not days—is also critical,” says Dr. Short.

      The CDC reports that several considerations should be taken into account for all patients treated with antiretroviral non-occupational PEP (Table 3). Using a starter pack of medications for 3 to 5 days and scheduling a follow-up visit to review the results of baseline HIV testing are among the actions to be considered. Additional counseling and support, assessments of medication side effects and adherence, and additional medications may be necessary.

      “Consultation with infectious disease or other HIV-care specialists might also be warranted before prescribing non-occupational PEP,” says Dr. Short. “Adherence to antiretroviral medications can be challenging—even for 28-day durations—so taking steps to maximize medication adherence can help.” Such efforts may include prescribing medications with fewer doses and fewer pills per dose, educating patients, or offering ancillary medications for side effects.

      Furthermore, the CDC states that all patients seeking care after HIV exposure should receive HIV antibody testing at baseline and at 4 to 6 weeks, 3 months, and 6 months after exposure to determine whether HIV infection has occurred. Testing for sexually transmitted diseases, hepatitis B and C, and pregnancy should also be offered. Dr. Short adds that HIV prevention counseling may be beneficial “because the majority of people who seek care after a possible HIV exposure do so because of failure to initiate or maintain effective risk-reduction behaviors.”

      Dr. Short has indicated to Physician’s Weekly that he has worked as a paid speaker for Tibotec, Abbott, and Gilead Sciences. He has also received grants/research aid from Gilead Sciences.