Growth in children after bone marrow transplantation

Growth velocity pattern and growth hormone (GH) secretion were evaluated in 18 prepubertal patients (13 males, 5 females), receiving an allogeneic (7 patients) or autologous (11 patients) bone marrow transplantation (BMT). Children were affected by oncological or hematological malignancies and the age range was between 2 and 11 years. Nine patients received a conditioning regimen consisting of chemotherapy and fractionated total body irradiation (TBI) (12 Gy in 6 fractions over 3 days), whereas 9 children also received previous prophylactic cranial irradiation during first-line chemotherapy. GH secretion in response to pharmacological stimuli (insulin, arginine and/or L-Dopa) was evaluated when growth failure occurred. The 9 prepubertal patients who had received previous prophylactic cranial irradiation during first-line chemotherapy, showed a significant decrease in growth rate already 1 year after BMT and this reduced growth rate presented a progressive further decrease in the 2nd and 3rd year after BMT. On the contrary, in the 9 prepubertal children treated with TBI and chemotherapy alone, growth rate presented an impressive decrease only during the 3rd year. In the two groups of patients, pretransplantation growth rates were comparable, while, due to the earlier growth failure in children receiving TBI and previous prophylactic cranial irradiation, mean standard deviation score (SDS) significantly differed at 1 and 2 years following BMT. Such a difference disappeared at 3 years after BMT, because of the late decrease in growth rate in patients given TBI and chemotherapy alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant human erythropoietin is effective in correcting erythropoietin-deficient anaemia after allogeneic bone marrow transplantation

Two children affected by severe aplastic anaemia (SAA) underwent allogeneic bone marrow transplantation (BMT) using partially matched family donors. In both cases there was a successful engraftment of donor haemopoietic stem cells. However, after an initial erythropoietic recovery, 5 months following BMT both children became severely anaemic. Although multiple factors were responsible for anaemia, in both cases there was a markedly impaired erythropoietin response to anaemia, as indicated by the inappropriately low levels of serum erythropoietin (EPO). Treatment with recombinant human erythropoietin (rHuEPO) induced a sustained erythropoietic response with complete correction of anaemia. This pilot study suggests that rHuEPO can be effective in correcting long-lasting anaemia after marrow transplantation, characterized by inadequate erythropoietin production.

Effect of corticoid therapy on growth hormone secretion

Exogenous corticoids are known to be potent inhibitors of linear growth in children. We investigated the mechanisms underlying growth failure by evaluating growth hormone (GH) release during short-term high-dose prednisone treatment (40 mg/m2/day given orally in 3 divided doses) and 7 days after steroid withdrawal in 7 prepubertal children (4 males, 3 females, age range 3-12 years), affected by acute lymphoblastic leukemia. Patients also received weekly administrations of vincristine (1.5 mg/m2 i.v.), daunomycin (20 mg/m2 i.v.) and L-asparaginase (6,000 IU/m2 i.m.). Corticoid therapy suppressed GH secretion during deep sleep as well as in response to arginine, insulin and GH-releasing hormone (GHRH) administration. A significant recovery of GH responsiveness after drug discontinuation was observed during deep sleep (14.03 +/- 3.47 vs. 1.49 +/- 0.43 ng/ml, p less than 0.025) as well as in response to arginine (13.63 +/- 2.73 vs. 4.95 +/- 1.54 ng/ml, p less than 0.025) and GHRH (32.62 +/- 4.59 vs. 7.27 +/- 3.52 ng/ml, p less than 0.005) but not to insulin (7.12 +/- 0.88 vs. 4.47 +/- 0.96 ng/ml, p = NS). Insulin-like growth factor 1 levels during deep sleep (0.61 +/- 0.13 IU/ml/min) were found to be low in the course of steroid therapy and did not increase after drug withdrawal (0.41 +/- 0.07 IU/ml/min). Our preliminary data suggest that recovery of adrenergic response to insulin does not immediately follow corticosteroid discontinuation.

[Gonadal function in adolescents after total body irradiation in bone marrow transplantation]

Gonadal impairment has been observed in patients who underwent bone marrow transplantation with TBI-containing cytoreductive regimen. In order to study the effects of radiations on the pituitary and gonadal hormones 12-18 months after transplantation sexual development and plasma levels of gonadotropins, estradiol, and testosterone were evaluated in 9 patients (4 boys and 5 girls, age range 11-20 years). The preliminary results of this study show that TBI produces in both sexes a gonadal impairment, as shown by the high plasma levels of gonadotropins. Nevertheless, the gonadal damage seems to be more important in girls and we suppose a greater sensitivity to radiation injury of the ovary than of the testis.