Hipotireoidismo congênito diagnosticado no sexto dia de vida: um relato de caso

INTRODUCTION: Congenital hypothyroidism results from insufficient secretion of thyroid hormones, which are related to the maturation of the central nervous system, being the main cause of preventable intellectual disability in childhood. The diagnosis can be suspected from the neonatal screening test, revealing its importance, since most cases are asymptomatic or oligosymptomatic at birth with nonspecific manifestations, as well as the classic manifestations become evident only later, causing neurological damage. OBJECTIVE: describe a clinical case of a patient diagnosed with congenital hypothyroidism on the sixth day of life, screened through the neonatal screening test, with subsequent laboratory confirmation, highlighting points of diagnosis, treatment and clinical follow-up, avoiding the progression of late diagnosis. CASE REPORT: male patient, born through normal delivery without complications, who developed asymptomatic hypoglycemia at the first hours of life, treatment resistant. The patient presented alterations compatible with congenital hypothyroidism in the neonatal screening test, with subsequent confirmation through laboratory tests. Thyroglobulin replacement was started on the seventh day of life, with progressive improvement in hypoglycemia and favorable clinical evolution throughout the first months of life. CONCLUSION: Congenital hypothyroidism is the main cause of preventable intellectual disability in childhood, it must be diagnosed as early as possible, demonstrating the importance of neonatal screening tools. After the institution of appropriate treatment and clinical follow-up, the evolution is favorable, avoiding the drastic progression of late diagnosis.