Endocrine complications in patients with Thalassaemia Major.

Patients with multi-transfused thalassaemia major may develop severe endocrine complications due to iron overload. The anterior pituitary is particularly sensitive to iron overload which disrupts hormonal secretion resulting in hypogonadism, short stature , acquired hypothyroidism and hypoparathyroidism. Glucose intolerance and diabetes mellitus are also common in thalassaemic patients. The severity of the clinical manifestation and laboratory findings in thalassaemia largely depends on the genotype; thus homozygotes or compound heterozygotes for the mutations beta0 or beta+ depend for life on frequent transfusions. A multicenter study in Cyprus including 435 patients showed hypogonadotrophic hypogonadism in 32.5%, short stature in 35%, acquired hypothyroidism in 5.9%, hypoparathyroidism in 1.2% and diabetes mellitus in 9.4%. A slowing down of growth velocity and a reduced or absent pubertal growth spurt is observed in early adolescence leading to short adult height. Delayed or absent puberty and hypogonadism may result in fertility problems which affect enormously the life of thalassemics. Glucose intolerance in adolescence and diabetes mellitus later in life are also frequent complications mainly due to iron overload, chronic liver disease and genetic predisposition. Primary hypothyroidism and hypoparathyroidsm usually appear in the second decade of life; are related to iron overload and may be reversible at an early stage by intensive chelation. Osteopenia and osteoporosis due to a complicated pathogenesis represent prominent causes of morbidity in young adults of both genders with thalassaemia. Early recognition and prevention of the endocrine complications, by early and regular chelation therapy, is mandatory for the improvement of the quality of life and psychological outcome of these patients.

The impact of iron overload and genotype on gonadal function in women with thalassaemia major.

OBJECTIVE: The purpose of this study is to evaluate the impact of chronic iron overload and genotype on gonadal function in women with thalassaemia major. PATIENTS AND METHODS: The study population consists of 101 women aged 15-48 years who were treated between 1981 and 1999. These women were divided into two groups according to their genotype: [A=no modifying genetic factor and B=presence of modifying factors], and into four groups according to their menstrual history: NM (normal menstruation), OLM (oligomenorrhea), PA (primary amenorrhea), and SA (secondary amenorrhea). RESULTS: Women with NM maintained eumenorrhoea for 14.62 years, whereas those with SA did so for 6.94 years. The serial values of both FSH and LH after stimulation with GnRH were lower in women with SA and PA (p<0.05) compared to women with OLM and NM. The average value of the minimum, mean and maximum ferritin levels over a period of 20 years displayed an increasing trend from women with NM to those with SA and PA. The lower levels of ferritin in women in Group A did not protect them from developing SA. In addition women with SA, who belong to Group A, had a shorter duration of eumenorrhoea compared to the ones with SA who belong to Group B. CONCLUSIONS: Although the pathogenesis of gonadal dysfunction in thalassaemia is known to be the consequence of iron overload, this study demonstrates that genotype acts as an independent variable, contributing to the development of SA in thalassaemic women.