An unusual cause of neonatal coagulopathy and liver disease.

Congenital thyrotoxicosis is a rare and potentially fatal illness. We report a case in a preterm infant delivered to a mother known to have autoimmune endocrine disease. Diagnosis was difficult because the infant's presenting symptoms and signs closely resembled congenital viral infection with co-existent hepatic dysfunction and coagulopathy. The associated hepatic dysfunction was so severe that liver biopsy was scheduled before the diagnosis emerged. A high degree of clinical suspicion coupled with prenatal identification of pregnancies at risk of complication by congenital thyrotoxicosis is imperative to facilitate prompt diagnosis and treatment.