Endocrinopathies in adolescents with thalassaemia major receiving oral iron chelation therapy

Endocrinopathies are common in patients with thalassaemia major (TM) despite parenteral iron chelation therapy with deferoxamine. There are only a few studies on the efficacy of oral deferiprone in preventing endocrine dysfunction.

To determine the growth and endocrine complications in children with TM receiving oral iron chelation with deferiprone.

All adolescents with TM receiving regular blood transfusion and deferiprone were evaluated prospectively for growth and pubertal status over a 1-year period. Tests for endocrine function included oral glucose tolerance test, calcium, phosphate, alkaline phosphatase, parathyroid hormone and thyroid profile and, in those with delayed/arrested puberty, sex steroids and gonadotropins. Clonidine-stimulated growth hormone (GH) was measured in patients with height ≤-3 SD.

89 patients [51 males, 38 females, mean (SD) age 13·6 (2·5) years] were evaluated. Mean (SD) pre-transfusion haemoglobin was 9·2 (1·1) g/dl and the mean (SD) age of starting deferiprone was 5·1 (2·4) years. Mean (SD) ferritin was 9159 (3312) pmol/L (normal <2247). 49 (55%) subjects were of short stature and 25 (27%) had a height Z-score ≤ -3. GH testing was performed in 19 patients, of whom 17 had peak GH values <10 μg/L. Delayed puberty and/or hypogonadism was present in 54·1% patients at or beyond the age of normal puberty. Impaired glucose tolerance/diabetes mellitus, hypoparathyroidism and primary hypothyroidism (subclinical) were present in 13·0%, 10·1% and 8·9%, respectively. Overall, 44 (49·4%) adolescents had at least one endocrinopathy.

Adolescents with TM on oral iron chelation therapy with deferiprone experienced a high prevalence of growth faltering and endocrinopathies which was comparable to that previously reported with deferoxamine. A combination of deferoxamine and deferiprone may be necessary to prevent growth and endocrine problems.