Low serum carnitine in HIV-infected children on antiretroviral treatment

Objective: 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. Design and setting: Cross-sectional study performed in a tertiary care hospital. Subjects: A total of 79 HIV-infected children on antiretroviral therapy, monitored prospectively in our hospital. Interventions: 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. Results: 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). Conclusions: 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.