Growth retardation in children receiving long-term total parenteral nutrition: effects of ornithine alpha-ketoglutarate.

We evaluated the effect of ornithine ketoglutarate (OKG) in reversing abnormal growth in six prepubertal children receiving total parenteral nutrition (TPN) for 5-10 y. They were 1-4 SDs below their expected 50th percentile for height. The energy and nitrogen intakes were unchanged from 8 mo before the beginning of the study until its completion. Two consecutive periods of 5 mo each were studied. OKG (15 g) was added to the parenteral solution during the first period (OKG+) but not during the second period (OKG-). Height velocity (HV) increased (P < 0.05) from a median of 3.8 cm/y to 6.45 cm/y (range 1.8-6.7) during the OKG+ period, and decreased (P < 0.05) to a median of 3.65 cm/y in the OKG- period. Plasma concentrations of insulin-like growth factor 1 (IGF1), glutamine, and glutamate increased (P < 0.05) during the OKG+ period. Variations of IGF1 concentrations correlated with HV variations (r = 0.82, P < 0.005) during both periods. This study demonstrates that OKG is associated with statural growth acceleration and increased IGF1 concentrations.