Developmental Outcomes in Early-treated Congenital Hypothyroidism: Specific Concern in Tc99m Thyroid Scan Role

Background Congenital hypothyroidism (CH) may cause alterations in the child's global development. The current study aimed to screen the global development of children with and without congenital hypothyroidism, focusing on communication, and cognitive abilities and to investigate the influence of illness severity, clinical history, and treatment factors in the evaluated results. Materials and Methods A case control study was conducted on 20 children with early-treated congenital hypothyroidism (CH), and controls without CH (n=100), both groups were matched for age and sex. Patients were subjected to a protocol of assessment applied in Pediatric and Phoniatrics Unit Sohag, Egypt. Assessments included detailed history and medical data, language development testing, intelligence quotient (IQ). According to TSH and T4 levels, case group was divided into controlled group and uncontrolled group.  99m pertechnetate scintigraphy of thyroid (Tc-99m TS) was recommended for all CH children.  Results Children’s ages ranged between 3-7 years with a mean age of (4.6 ±1.9year). There were statistically significant differences between study and control group in presence of middle ear effusion, delayed language development, IQ scores (p<0.001). Interestingly, there was a negative correlation between IQ test and total language age with TSH level (r = -0.06, p= 0.004; r =-0.4, p=0.06), respectively. Tc-99m pertechnetate scintigraphy of thyroid confirmed transient CH diagnosis in three cases. Conclusion Despite early treatment in the studied CH children, language and cognitive skills impairments were detected. The magnitude of these impairments significantly related to TSH values and regularity of hormone replacement therapy. TS confirmed transient CH diagnosis in three cases, replacement therapy stopped in those children.