Evaluating the Patients with Thalassemia Major for Long Term Endocrinological Complicatoins after Bone Marrow Transplantation

Many vital organs, including the endocrine glands, are affected by iron deposition in thalassemia major (TM) patients causing significant growth and endocrine disturbances. The progressively increasing number of long-term survivors after allogeneic bone marrow transplantation (BMT) led the researchers to focus on the early and late complications of this procedure. The aim of this study was to evaluate the endocrinological complications of the patients with TM who underwent bone marrow transplantation (BMT) and followed-up more than two years in our centre. Fourty one patients with TM (15 boys, 26 girls) in the "transplantation group", who were performed bone marrow transplantation between January 1998 and January 2007 in Pediatric Stem Cell Transplantation Unit in Akdeniz University Faculty of Medicine, evaluated during the study. Their age ranged 3,3-24 years and transplantation age of the patients was mean 7,5±4,9 years. Post-BMT follow-up lasted from 24 to 122 months (mean 65,07 months). Thirty two patients with TM (13 boys, 19 girls), in the similar age group and with the same history of transfusion and chelation entered the study as the "control group". In addition to detailed endocrinologic examination and anthropometric measurements of the patients, bone metabolism parameters (serum calcium, phosphor, alkaline phosphatase and intact parathormone), thyroid stimulating hormone, follicle stimulating hormone, cortisol, adrenocorticotropic hormone, estradiole for girls, testosterone for boys, blood glucose, insulin, IGF-1, IGF-BP3, ferritin and hemoglobin values obtained from both two groups. Compared with the controls, there was no statistical difference for short height in the transplant group (p=0,68). In transplantation group mean height SDS score before BMT was -1,42±0,26 and mean height SDS score after transplantation was -1,21±0,23 and there was no statistical difference (p=0,96). The weight SDS score after transplantation was found better than before transplantation (p=0,010). Significantly adverse correlations was founded between height SDS and BMT age (p=0,008). Height SDS values were lower in the patients with increased BMT age but no relationship was seen between BMT age and weight SDS values. The height SDS scores founded better in patients whose BMT age was under seven years old compared to older than seven years old (p=0,02). Z scores of femur neck and L2-4 vertebra were decreased (p=0,032, p=0,0001) and the risk of the insulin resistance increased (p=0,01) in the patients with increased BMT age. In the patients who underwent the transplantation under 7 years of age, the risk of the gonadal insufficiency was founded significantly lower than the patients whom BMT was performed over 7 years (p=0,009). There was no statistically significant relationship between BMT age and the complications such as hypothyroidism, hypoparathyroidism and adrenal insufficiency. In this study we founded that the height SDS and DEXA Z scores were significantly better and the frequency of the hypogonadism and insulin resistance were significantly lower in the patients who underwent BMT before 7 years of age. For this reason, we suggest that, the patients with TM should be evaluated for transplantation in early stage of the disease. Because of the bone marrow transplantation can not correct the endocrinological complications of TM completely, the patients should be followed up regularly after the transplantation.