Background: Argentina has the sixth largest number of cumulative pediatric cases of acquired immunodeficiency syndrome (AIDS) in the Americas; therefore, this study was designed to characterize human immunodeficiency virus-1 (HIV-1) infection in children in Buenos Aires, Argentina.
Materials and methods: Medical records of 389 children at risk and infected with HIV-1, an urban population followed by the AIDS Reference Center at the Hospital de Niños "Dr. Ricardo Gutiérrez" of Buenos Aires, from February 1990 to June 1997, were retrospectively reviewed. Mother-infant pairs were analyzed according to clinical and epidemiologic patterns.
Results: Perinatal transmission occurred in 94.9% of the 389 cases classified as seroreverter (n=104, 26.7%), exposed (n=64, 16.4%), asymptomatic (n=13, 3.4%), and symptomatic patients (n=208, 53.5%); 132 patients met the Centers for Disease Control and Prevention (CDC) criteria for AIDS. The main maternal risk factor was sexual transmission 58.9% (73.4% of their sexual partners were injection drug users [IDU]). Among the AIDS patients, the most common AIDS-defining condition and death-related disease were severe bacterial infection and Pneumocystis carinii pneumonia, respectively. Death occurred in 51 of 221 HIV-infected children. Low CD4 was related to death (P < 0.001). Mortality was estimated for two periods: January 1990 to December 1995 (G1) and January 1996 to May 1997 (G2). In G1, 37 of 127 (29.1%) died compared with 14 of 154 (9.1%) in G2 (P=0.001). The median age of death was 10 months for G1 and 29 months for G2 (P=0.01). The 3-year survival rate was 72% for G1 and 87% for G2 (log rank P=0.06).
Conclusions: Intravenous drug use is the leading risk factor among parents of children exposed to HIV. Infant mortality was related to age less than 12 months, low CD4 count, severe bacterial infection and P. carinii pneumonia. In this study, P. carinii pneumonia prophylaxis and combined antiretroviral therapy routinely implemented since 1996 has demonstrated a trend toward increased survival rates (P=0.06) and a lower mortality rate (P=0.001).