Congenital hypothyroidism in Saudi population in two major cities: A retrospective study on prevalence and therapeutic outcomes

OBJECTIVE: Congenital hypothyroidism (CH) is a common cause of preventable severe neurocognitive impairment in children. Previously conducted studies describing the natural history of CH in Saudi Arabia were either of shorter duration or a limited number of patients. In this study, we aim to assess our experience in the clinical course and therapeutic outcome of CH in two large tertiary centers in Saudi Arabia. METHODS: This is a retrospective chart review of patients <18 years of age diagnosed with CH at King Abdulaziz Medical City in Jeddah and Riyadh, Saudi Arabia, between 2000 and 2018. Data were collected from the patients’ medical records, including epidemiological, clinical, laboratory, and radiological features as well as a long-term outcome of CH. Statistical analysis was carried out using the JMP statistical software. This study was approved by the Institutional Review Board (IRB) at King Abdullah International Medical Research Center (KAIMRC). RESULTS: Out of the 71 cases, 53.5% were female, and 80.3% of these cases were diagnosed in the 1(st) week of life. The estimated incidence of CH is 1:2470 in the two study centers. Ectopic thyroid (43%, n = 25/58), dyshormonogenesis (34.5%, n = 20/58), and thyroid agenesis and hypoplasia (22.4%, n = 13/58). Learning difficulty was significantly associated with delayed treatment onset (P = 0.044) and lower compliance with treatment (P = 0.001). CONCLUSION: In our study, the incidence of dyshormonogenesis in CH is higher than international rates (34.5% vs. 20%), possibly because of consanguinity. Effective neonatal screening program facilitates early diagnosis that leads to prompt management of CH and avoidance of long-term outcome of neurocognitive impairment.