Ritonavir combination therapy restores intestinal function in children with advanced HIV disease

Objectives: To investigate the intestinal absorptive processes in children with HIV infection before and after treatment with combination therapy that includes ritonavir. To test the hypothesis that combination therapy improves intestinal function. Design: Intestinal function tests were performed in 10 children with advanced HIV disease at the enrollment and after 3 and 6 months of therapy with ritonavir combined with two HIV reverse transcriptase inhibitors. HIV viral load and CD4 cell counts were also determined; body weight was monitored. Methods: The D-xylose absorption test, the steatocrit and the determination of fecal alpha(1)-antitrypsin concentration were used to evaluate carbohydrate and fat absorption, as well as fecal protein loss. Serum iron levels were measured to indirectly evaluate iron absorption. HIV-I RNA-polymerase chain reaction (PCR) and immunofluorescence imaging were used to evaluate virologic and immunologic responses. Results: In all, 9 children had carbohydrate malabsorption, 3 steatorrhea, 2 protein loss, and 7 iron deficiency. Most tests produced normal results after 3 months of therapy, and all abnormalities were abolished 6 months after institution of combination therapy. Mean results of each of four absorption tests were significantly changed on combination therapy. Viral load was progressively reduced and CD4 count was increased, with an inverse relationship. An evident shift of body weight pattern toward catch-up growth was observed in all children. Conclusions: Ritonavir combination therapy results in prompt and sustained restoration of intestinal function, which is associated with reduction in viral load, increase in CD4 counts, and gain in body weight.