To 'umbrella' the gonads in transfusion rain.

Sir,

Hypogonadism is an important and most common endocrine complication arising in transfusion-dependent diseases like thalassemia. About half of thalassemia patients over 15 years of age tend to develop hypogonadism with a male preponderance. Hypogonadotropic hypogonadism secondary to siderosis (serum ferritin levels above 2000 μg/L) underlies this complication.[1] Short stature, another usual accompaniment of hypogonadism results from reduced growth hormone response, low insulin-like growth factor I levels. Other disorders resulting from iron overload include hypothyroidism, hypoparathyroidism and diabetes mellitus although serum ferritin is usually more than 3000 μg/L in these entities.[2] Increased incidence of cardiomyopathy, endocrinopathy, cirrhosis, hepatocellular carcinoma osteopenia/osteoporosis, hepatitis C and hepatitis B has also been noted. There is ample evidence that the incidence of hypogonadism is considerably higher in patients who received transfusions earlier and iron chelation therapy later in life. Conversely, earlier chelation therapy (in the first years) with constantly good compliance may show normal growth and sexual maturation.

Clinically, hypogonadotropic hypogonadism may manifest with failure of puberty, arrested/delayed puberty, amenorrhea (primary or secondary) or irregular menstrual cycles. Hormone replacement therapy may have a role to provide normal sexual maturation. Genetic differences in thalassemia major and the hematologic phenotype may mediate the varying susceptibility to hypogonadotropic hypogonadism, possibly as a result of differences in the amounts of blood transfused and/or their vulnerability to free radical damage.[3]

Plasma nontransferrin-bound iron levels are characteristically lower in sickle cell disease than in thalassemia patients at matched iron overload levels. Sickle cell patients have raised plasma hepcidin due to chronic inflammation, have lower growth differentiation factor-15 levels due to less ineffective erythropoiesis, and induce heme oxygenase by intravascular hemolysis. These mechanisms may explain the lesser incidence of extrahepatic complications including hypogonadism in sickle cell patients compared to thalassemia.[4]

Luteinizing hormone/follicle-stimulating hormone (LH/FSH) and estradiol routinely used to predict the fertility potential in thalassemia have not proved consistently reliable, and other markers of ovarian reserve testing and liver iron concentration may be better indicators in fathoming the presence of hypogonadism. In magnetic resonance imaging (MRI) the pituitary-to-fat signal intensity ratios and the pituitary height and volume are significantly lower in hypogonadotropic hypogonadism (with the former occurring earlier than the latter) compared to controls which are pointers in delineating the disorder. MRI may also quantify the pituitary iron deposition.

Combination therapy (use of two chelators on the same day), promises increased efficacy and may induce negative iron balance in these patients. Long-term studies have shown that deferiprone and deferoxamine (DFO) have shown to accelerate iron chelation by rapidly reducing liver iron, serum ferritin, and myocardial siderosis. The combination has also reversed and prevented hypogonadism and endocrine complications, reduced cardiac mortality and improved survival. Combination chelation therapy with deferasirox and DFO has also been shown beneficial.[5]

The ultimate goals of preventing gonadal jeopardy, preserving fertility and reproductive ability in these entities can be achieved by having a high index of clinical suspicion, administering scrupulous transfusions and superior tailoring of iron chelation to the needs of the patients.