Whole body protein turnover in children with human immunodeficiency virus (HIV) infection

The purpose of this study was to determine the rate of whole body protein t urnover (WBPT) in human immunodeficiency virus (HN)-infected children, and to determine the relationship between WEPT and growth. The rate of WEPT was calculated from the cumulative excretion of labeled urinary ammonia after a single intravenous dose of N-15-glycine in three groups of children: 1) H IV+ with growth retardation (HIV+Gr); 2) HIV+ with normal growth (HIV+); an d 3) HIV-uninfected with normal growth (HIV-). Twenty-six children between 2 and 11 y of age were studied (10 HIV+Gr, 12 HIV+, 4 HIV-). All children w ere afebrile and free of acute infection during the study. Rates of WEPT (m ean +/- SD) for the study groups were: HIV+Gr, 12.2 +/- 4.8; HIV+, 10.7 +/- 5.1; and HIV-, 8.6 +/- 2.1 g.protein.kg(-1).d(-1) (NS, P > 0.05). Although not statistically significant, mean WEPT was 42% greater in HIV+Gr, and 24 % greater in HIV+ compared to HIV-. Statistically significant correlations were found between WEPT and Z scores' for height (r = -0.39, P = 0.05) and weight-for-age (r = -0.51, P = 0.01) and dietary intake of protein (r = 0.3 9, P = 0.05), and between protein balance (synthesis-catabolism) and intake s of energy (r = 0.47, P = 0.02) and protein (r = 0.40, P = 0.04). There wa s no statistically significant correlation between WEPT and resting energy expenditure (r = 0.27, P = 0.19), or CD4 cell number (r = 0.05, P = 0.82). These data suggest an association between increased rates of protein turnov er and low weight and height-for-age Z scores, and that it may be possible to achieve positive protein balance given an adequate intake of nutrients. Nutrition 1999;15:189-194. (C)Elsevier Science Inc. 1999.