Right-sided Thyroid Hemiagenesis in a Male Newborn with Congenital Hypothyroidism: A Case Report with Review of Literature

Abstract

Background: Thyroid hemiagenesis (THA) is a rare aberration in the development of the thyroid gland, denoted by the absence of either thyroid lobe with or without the isthmus, common in females, predominantly involving left lobe of thyroid, usually maintaining a euthyroid state. Clinical Description: A premature male baby born at 34 weeks gestation with birth weight 1100 g was admitted in the neonatal intensive care unit (NICU) for respiratory distress soon after birth. The antenatal period was uneventful and maternal thyroid status was within normal limits. Management and Outcome: While the newborn was being stabilized in NICU, the results of routine cord blood screening revealed raised thyroid-stimulating hormone levels, following which an ultrasound examination showed right THA, confirmed further by technetium-99 radionuclide scan. Thyroxine was initiated for persistent hyperthyrotropinemia. The baby was eventually discharged and was doing well till 6 months of follow-up. Conclusion: Unlike the common scenario published in literature, our case of THA was seen in a male newborn, involving the right lobe of the thyroid along with a hypothyroid state. As THA is a state of continuous overstimulation of thyroid tissue, newborn screening and detection of this abnormality at this early age is important.