Dopamine infusion: a possible cause of undiagnosed congenital hypothyroidism in preterm infants.

OBJECTIVE: To describe the possibility that dopamine infusion can prevent early diagnosis of congenital hypothyroidism. DESIGN: Case report. SETTING: Medical neonatal intensive care unit of a tertiary academic medical center. PATIENTS: We report four preterm newborns affected by transient primary congenital hypothyroidism who showed low serum thyroxine and normal thyroid-stimulating hormone concentrations on primary screening performed during treatment with dopamine. INTERVENTIONS: Thyroid reevaluation screening after dopamine discontinuation. MEASUREMENTS AND MAIN RESULTS: Thyroid reevaluation showed elevated thyroid-stimulating hormone levels. CONCLUSION: We emphasize that dopamine capacity to suppress thyroid-stimulating hormone could prevent early diagnosis of congenital hypothyroidism. We suggest all newborns to be tested simultaneously for thyroid-stimulating hormone and thyroxine values at primary screening. A reevaluation of thyroid hormones after dopamine discontinuation is advisable in patients treated with dopamine.