Background: Acquired primary hypothyroidism in neonates and infants under 3 years of age is very rare. Herein we report the case of an infant female affected by acquired autoimmune hypothyroidism.
Patient report: The infant was transferred to the Pediatric Clinic, University of Catania, Italy for evaluation of dysmorphic features, growth and motor retardation, and hypothyroidism on laboratory testing. Neonatal screening test for TSH and PKU was negative. An ultrasound scan showed a non-homogeneous thyroid gland which was increased in volume. Based on the laboratory results, the diagnosis of autoimmune hypothyroidism was made and L-thyroxine treatment was initiated at 50 microg/day.
Conclusions: Autoimmune hypothyroidism in infancy is rare, but early recognition and therapy are essential to prevent neurologic damage and growth deficits. In this patient we would like to underline the early age of appearance of autoimmune thyroid disease and the possible onset of pathologic events before birth.