Endocrine and Growth Disorders in Children with Haemoglobin-SS

Abstract

Background: Suboptimal growth and certain metabolic disorders are commonly presented by children with Sickle Cell Disease (SCD). SCD is an autosomal recessive genetic condition common in regions with intense malaria prevalence. The cycles of de-oxygenation and oxygenation of red
blood cells producing repeated sickling and unsickling, leading to red cell damage is a concern. There was need to establish the cause of common triggers for Vaso-Occlusive crises which include dehydration, infections, extreme temperature and emotional stress. Recurrent painful episodes, several physical and biochemical disorders including suboptimal growth, low immunity, anemia and a variety of serious organ system complications that cause life-long disabilities and/or early death in HbSS patients was a challenge. The highest frequencies (3 to 4% of populations) of Homozygous Sickle Cell disease occur in Sub-Saharan Africa.

Methodology: Twenty eight children aged 4-10 years with Hemoglobin-SS (HbSS) and Vaso-Occlusive crisis attending Children Emergency Clinic at  Ladoke Akintola University of Technology Teaching Hospital and another 30 healthy sex and age matched children with HbAA (controls) participated
in this study. Plasma levels of Growth Hormone(GH), cortisol, prolactin, Total Thyroxin(TT4), Total Triiodotyronine(TT3), Thyroid Stimulating  Hormone(TSH) and insulin were determined in all respondents using enzyme linked immunosorbent assay methods.

Results: The weight, height and BMI decreased significantly (p<0.05) in HbSS children compared with the controls. Plasma levels of GH, cortisol, TT3 and TT4 increased significantly (p<0.05) in HbSS-children compared with controls. Plasma levels of prolactin, TSH and insulin did not show significant (p>0.05) changes in the HbSS children compared with the controls. There was a significant (r=0.46, p=0.04) positive correlation between cortisol and GH in the children with HbSS. A negative correlation (r=-0.45, p=0.045) existed between TT4 and weight of HbSSchildren.

Conclusion: The lower levels of height, weight and BMI despite increased plasma level of GH could suggest peripheral tissue resistance and/or GH-receptor deficiency in HbSS children. Elevated cortisol levels and the positive correlation between cortisol and GH could suggest a link between metabolic stress and GH secretion in HbSS Children.

Key words: Hormones, growth disorders, Haemoglobin-SS(HbSS)