[Correlation between serum L-carnitine concentration and neutrophil engraftment in patients treated with cord blood transplantation].

In cord blood transplantation (CBT), the amount of time elapsing until hematological engraftment has effects on the transplantation results. Carnitine deficiency has been reported to cause erythropoietin refractory anemia in chronic hemodialysis patients and thrombocytopenia or leukopenia of cirrhosis, and carnitine supplementation can improve hematopoiesis in patients with hepatic or renal failure. Patients who receive CBT may suffer from carnitine deficiency, but no studies have investigated the carnitine status of such patients. Herein, we determined the concentration of free carnitine (FC) and investigated the correlation between FC and engraftment in patients who received CBT. Twenty-three patients who received CBT at our hospital during the period from April 2013 to January 2015 were enrolled in this study. One patient was excluded because of graft failure, such that 22 patients were ultimately evaluable. FC concentrations of the patients were sequentially monitored at 4 time points (before conditioning therapy, day 0, day 7, and day 14), basic laboratory data were collected, and their correlations with engraftment were analyzed. FC concentrations of the patients were generally low (before conditioning therapy: 33.1, day 0: 43.2, day 7: 38.3, and day 14: 37.8 µmol/l). Significant inverse correlations were observed between FC concentrations and the number of days required for neutrophil engraftment on day 0 and day 14 (before conditioning therapy: P=0.15, r=-0.33, day 0: P=0.04, r=-0.43, day 7: P=0.30, r=-0.23, and day 14: P=0.01, r=-0.55). These results suggest carnitine to be an important nutrient that promotes hematopoietic recovery after CBT.