Changing patterns of clinical events in perinatally HIV-1 infected children during the era of HAART.

Background: The introduction of HAART has decreased mortality and progression to AIDS in perinatally HIV-1-infected children, but information on modification of the rate of specific clinical events is limited. Method: An observational population study on changes in HIV-1-related morbidity was conducted on 1402 perinatally HIV-1-infected children enrolled in the Italian Register for HIV Infection in Children and prospectively followed in the pre-HAART (1985–1995) and post-HAART periods (1996–2000, and 2001–2005). Of this group, 773 children (55.1%) were followed from birth. Median observation time was 8.58 years (interquartile range, 3.71–13.72). Results: Overall, 666 (47.5%) children developed AIDS and 420 (29.9%) died. Improved survival over time was evidenced at Kaplan–Meier analysis (P<0.0001). Poisson regression analysis indicated that Centers for Disease Control and Prevention class B and C clinical event rates and most of the HIV-1-related organ complication rates significantly decreased starting from 1996–2000. Significant reductions in rates of cancer and opportunistic infections were evidenced after 2000. Nevertheless, opportunistic infections still occurred at high rates (6.09/100 person-years) in 2001–2005, with high rate of bacterial infections (3.55/100 person-years), particularly pneumonia (1.66/100 person-years), in this period. CD4 cell percentage was >15% in 58.5% children with pneumonia. Conclusions: Progressive reductions of both mortality and rates of class B and C clinical events, including organ complications, were evidenced in the HAART era. Nevertheless, severe bacterial infections, particularly pneumonia, still occurred at considerable high rates, even in the absence of a severe CD4 cell depletion