The Canadian Journal of CME / July 2004 101

When the AIDS epidemicemerged at the beginning of the 80s, it was the number one cause of death among people aged 20 to 40 until the mid-1990s. Highly active antiretroviral therapy (HAART) has significantly improved HIV-related mortality and morbidity since its introduc-tion in 1996. Prophylaxis guide-lines against opportunistic infec-tions were modified since HAART’s success, however, limi-tations of anti-HIV drugs have since emerged, relating to: • drug-specific resistance, • toxic side-effects, • drug interactions, and • high pill burden. Moreover, increases in CD4 levels do not always represent a complete reconstitution of immunity and are sometimes accompanied by an inflammatory syndrome known as immune reconstitution syndrome. Antiretroviral therapy Since the introduction of antiretroviral therapy (ART), modifications have been made based on time of initiation, the type of regimen to be used, and strategy taken after the initial failure of therapy. These modifications are related to the occurrence of drug resistance, drug toxicity, the advent of new drugs, and new laboratory assays to monitor outcome. There are currently 19 anti