Low serum carnitine in HIV-infected children on antiretroviral treatment

Abstract

HIV-infection and antiretroviral therapies are associated with energy dysfunction and lipid metabolism in adults. Our aim was to detect a possible carnitine deficiency in HIV-infected children on antiretroviral treatments. We analysed the relation among serum carnitine, its amino-acid precursors (methionine and lysine), clinical evaluation and antiretroviral therapy. Cross-sectional study performed in a tertiary care hospital. A total of 79 HIV-infected children on antiretroviral therapy, monitored prospectively in our hospital. Antiretroviral therapy included nucleoside analogues plus protease inhibitors and/or non-nucleoside analogues. Carnitine was analysed by an enzymatic-spectrometric procedure, and amino acids by ion exchange chromatography. Reference values of carnitine and amino acids were established in apparently healthy children who underwent presurgical analysis for minor surgery. Serum free and total carnitine, acylcarnitines, methionine and lysine were significantly lower in HIV-infected children compared with our reference values for similar ages (P<0.0001; Student's t-test). Low carnitine values were observed in 37% of our HIV-infected children. A significantly positive correlation was observed between serum total carnitine and methionine or lysine (P<0.0001 and P=0.005, respectively; Pearson test). No relation was observed between serum carnitine and clinical stage of HIV infection, immunological or nutritional status or lipodystrophy. Free and total carnitine were significantly lower (P=0.002 and 0.033, respectively) in HIV-infected patients on protease inhibitors (N=56) compared with those on other treatments (N=23). Low serum carnitine concentration was observed in 37% of our HIV-infected children on antiretroviral therapy. Malabsorption or defective synthesis may also account for the low serum carnitine values detected in these patients.