Surgical Pathology in HIV Infection in the Era of Antiretroviral Therapy
The natural history of infection with human immunodeficiency virus (HIV) has changed with the introduction of antiretroviral therapy (Fischl et al 1987), these drugs have the ability to inhibit viral replication and immune recovery of infected patients (Lalezari et al 1999). This has resulted in reduced mortality and morbidity caused by this viral infection (Mellors et al 1996). The human immunodeficiency viruses have extraordinary structural and evolutionary complexity since its original identification and description for over 25 years. Nine subtypes are known and three different subtypes, a total of 12, with subtype C HIV-1 responsible for more than half of infections in the world. The molecular and genetic study of HIV reflects the enormous and increasing variability of these organisms (Hue et al 2005). The HIV viruses are highly variable and are adapted to the selective pressure of antiretroviral drugs, hence antiviral treatments, which started 19 years ago have selected strains with resistance mutations that complicate or invalidate the continuity of certain treatments and sometimes of all. The geographical distribution and the percentage in the distribution of transmission pathways of the disease have changed over the past 25 years that have elapsed since the start of the epidemic (CDC, 2002). AIDS is an emerging disease in countries of the former Soviet Union, China, and sub-Saharan countries, the number of children and adults who are being infected is higher, producing a characteristic accelerating effect of prolonged epidemics. The AIDS program of the United Nations estimates that by the end of 2005, the total number of people worldwide living with HIV-/-AIDS was 40.3 million, 64% are in sub- Saharan Africa (WHO, 2005). In Europe 294,571 cases were reported in late 2004, 18.6% were women and 3.7% were children. The main transmission groups in Europe are injecting drug users (38.1%), homosexual contacts (29.5%), and heterosexual contacts (20%), although these parameters are not evenly distributed across the continent. While there has been an overall decrease of 6.7% over the previous year 2004 (HIV EURO 2005). In Mexico, the first case was diagnosed in 1983 and currently the largest number of cases (38.400) live in Mexico City, that is 17% of all HIV cases in the country for 2010. The age of onset is 15 to 49 years, 87% are men and 13% are women. The main route of infection is homosexual practice. In this country, AIDS is the third leading cause of death nationally among men 25 to 34 years and the sixth among women in this age group (http: // www. aid-sida-org/estadistic05.htlm).The clinical presentation of AIDS varies from one geographic area to another according to the most prevalent transmission groups. The purpose of this chapter is to conduct a general review of infectious agents and neoplasmas associated with some viral agents in the era of antiretroviral treatment of HIV- infected patients in specimens obtained by biopsy, surgical resection, or cytology material.