Opportunistic infections can occur in up to 40% of people with HIV infection and a CD4 count less than 250/mm3, although the risks are much lower with use of highly active antiretroviral treatment.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of prophylaxis for P carinii pneumonia (PCP) and toxoplasmosis? What are the effects of antituberculosis prophylaxis in people with HIV infection? What are the effects of prophylaxis for disseminated M avium complex (MAC) disease for people with, and without, previous MAC disease? What are the effects of prophylaxis for cytomegalovirus (CMV), herpes simplex virus (HSV), and varicella zoster virus (VZV)? What are the effects of prophylaxis for invasive fungal disease in people with, and without, previous fungal disease? What are the effects of discontinuing prophylaxis against opportunistic pathogens in people on highly active antiretroviral treatment (HAART)? We searched: Medline, Embase, The Cochrane Library and other important databases up to December 2004 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
We found 61 systematic reviews, RCTs, or observational studies that met our inclusion criteria.
In this systematic review we present information relating to the effectiveness and safety of the following interventions: acyclovir; antituberculosis prophylaxis; atovaquone; azithromycin (alone or plus rifabutin); clarithromycin (alone, or plus rifabutin and ethambutol, or plus clofazimine); clofazimine plus ethambutol; discontinuing prophylaxis for CMV, MAC, and PCP; ethambutol added to clarithromycin plus clofazimine; famciclovir; fluconazole; isoniazid; itraconazole; oral ganciclovir; rifabutin (alone or plus macrolides); trimethoprim-sulfamethoxazole; and valaciclovir.
Opportunistic infections can occur in up to 40% of people with HIV infection and a CD4 count < 250/mm3, although the risks are much lower with use of highly active antiretroviral treatment.
Trimethoprim-sulfamethoxazole or azithromycin may reduce the risk of PCP, but have not been shown to reduce toxoplasmosis infection.
Atovaquone may prevent PCP and toxoplasmosis in people who cannot take trimethoprim−sulfamethoxazole, although we don't know this for sure.
Tuberculosis can be prevented by standard prophylaxis in people who are tuberculin skin test positive, but not in those who are tuberculin skin test negative.
Short-term combination treatment has similar efficacy to long-term isoniazid monotherapy, but has greater risk of adverse effects.
Azithromycin or clarithromycin may reduce the risk of disseminated Microbacterium avium complex (MAC) disease in people without prior MAC disease.
Adding rifabutin may reduce the risk of MAC disease, while adding ethambutol decreases the risk of relapse, compared with other antibiotic regimens.Combination treatment with clarithromycin plus clofazimine may increase mortality and is usually avoided.
Aciclovir reduces the risk of herpes simplex virus (HSV) and varicella zoster virus infection and overall mortality, but has not been shown to reduce cytomegalovirus (CMV) infection.
Valaciclovir and ganciclovir may reduce the risk of CMV infection, but may be associated with serious adverse effects.
Fluconazole and itraconazole may reduce the risk of invasive fungal infections or their relapse, but can cause serious adverse effects.
In people with a CD4 cell count above 100−200/mm3, discontinuation of prophylactic treatment may not increase the risk of PCP, toxoplasmosis or MAC infection.