Effect of Zinc Status on Sexual Maturation in Children with Transfusion Dependent Thalassemia

Background: A child with thalassemia major has a particular growth pattern, which is relatively normal until age of 9–10 years; after this age a slowing down of growth velocity and a reduced or absent pubertal growth spurt are observed. Zinc is known to affect normal growth and sexual development and an estimation of 20% to 30%of patients with thalassmia are zinc deficient. Our aim was to determine the relationship between zinc status and Tanner stage to evaluate the effect of zinc deficiency on sexual maturation in transfusion dependent thalassemia. Methods: we included 40 children with transfusion dependent β-thalassemia and 40 sex and age matched apparently healthy children as control group. All children were subjected to thorough history taking and full medical examination with body mass index calculation and pubertal stage assessment using Tanner scale, serum zinc and ferritin levels were assayed. Results: there was a significant delay in sexual maturation assessed by Tanner staging in children with thalassemia than controls (p=0.003). Mean age of menarche in cases was 15.1 ± 1.7 years, this was significantly higher than that in controls which was 11.9 ± 1.3 years (p=0.001). Serum zinc in cases was 58.01±10.58 µg/dl, which was significantly lower than serum zinc of controls (68.37 ± 8.67 µg/dl, p = 0.001). Tanner stage was found to positively correlated with BMI and serum zinc (r= 0.54, p= 0.04 and r=0.22, p=0.012 respectively) and negatively correlated with serum ferritin (r=-0.34, p=0.03). Conclusion: Reduced serum zinc and iron overload in children with thalassmic patients was associated with delayed sexual maturation.