We gratefully acknowledge the contribution of Piccirillo et al to the discussion about glutamine supplementation in transplanted patients. In our original report, we have already mentioned patient heterogeneity as one variable that could contribute to our results. However, the glutamine patients were not disadvantaged by their disease status at transplant. If we count multiple sclerosis (MS) patients among those treated for advanced disease, then there were 15 patients in the glutamine group transplanted upfront and six patients with advanced disease. In the placebo group these numbers are 12 and 7. If we exclude the MS patients, the ratios will still be similar, with no statistical difference. As to the myeloablative potential of the conditioning regimens used in our study, we wish to emphasize that bone marrow toxicity is not equivalent to mucosal toxicity and in fact the mucosal toxicity of melphalan is its dose-limiting toxicity in conditioning regimens. However, the absence of other contributing factors to mucosal toxicity (namely GvHD) may be responsible for the lack of benefit of glutamine in ASCT patients.
It is not routine in our center to give all transplant patient parenteral nutrition from the beginning, as some other centers do. Most of our patients maintained good oral intake despite the need for opioid analgesia with the mean negative nitrogen balance being only −36.8 g in glutamine and −21.4 g in the placebo patients (difference not significant Beneš et al 1). Therefore, it is less probable that amino-acid imbalance could contribute to our results, although this aspect was not studied. As to lymphocyte regeneration, we can confirm similar trends to those of Piccirillo, although they have not reached statistical significance.
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