Treating Opportunistic Infections Among HIV-Infected Adults and Adolescents Infectious Diseases - Introduction       Opportunistic infections (OIs) continue to cause morbidity and mortality in patients with human immunodeficiency virus (HIV)-1 infection throughout the world. Potent combination antiretroviral therapy (ART) has reduced the incidence of OIs for certain patients with access to care. However, certain patients in the developed and developing world do not have access to care and have OIs. Other patients do not have a sustained response to antiretroviral agents for multiple reasons, including poor adherence, drug toxicities, drug interactions, or initial acquisition of a drug-resistant strain of HIV-1. Therefore, OIs will continue to cause substantial morbidity and mortality in patients with HIV-1 infection. The therapy of OIs has changed substantially during the AIDS epidemic. As more information about efficacy, toxicity, and interactions of the drugs to treat and prevent OIs has emerged, management strategies have evolved. New drugs have also become available that occupy important roles in our therapeutic armamentarium. These guidelines and the accompanying guidelines, Treating Opportunistic Infections Among HIV-Exposed and Infected Children, join two previous guidelines, The United States Public Health Service-Infectious Diseases Society of America Guidelines for the Prevention of Opportunistic Infections in Persons Infected with the Human Immunodeficiency Virus and The Department of Health and Human Services (DHHS) Guidelines for the Use of Antiretroviral Agents in HIV-Infected Adults and Adolescents. How To Use the Information in This Report    For each of the diseases covered in this report, specific recommendations are provided. Recommendations are rated by the IDSA rating system. In this system, the letters A through E signify the strength of the recommendation for or against a treatment measure, and Roman numerals I through III indicate the quality of evidence supporting the recommendation.