Aims 1. To assess current practice in diagnosis and management of babies with hypothyroidism admitted to a neonatal unit against national guidelines.

2. To assess the clinical profiles of cases with eventual outcome.

Method This was a retrospective casenote review of all babies with the diagnosis ‘hypothyroidism’ admitted to a tertiary neonatal unit between 2010–2015, identified on Badgernet. Clinical presentation, diagnosis and management information was collected on proformas created using the BPSED Congenital Hypothyroidism guidelines. Guthrie results were obtained to check correlation with serum thyroid function tests (TFTs).

Results 37 infants with hypothyroidism were identified. 30 case notes were reviewed; 22 male and 8 female. 21/30 infants had negative Guthrie tests. Of the 7/30 infants with a positive Guthrie, no specific pattern could be described. 16 infants were <32 weeks gestation, 14 infants were >32 weeks gestation.

15/30 babies had another abnormality, with the majority identified in babies>32 weeks gestation.

Commonest presentations in babies<32 weeks were prolonged neonatal jaundice and feed intolerance.

29/30 cases commenced treatment but most babies were treated after 28 days of age, largely due to delayed Guthrie results. 27/30 cases were referred to an Endocrinologist, with most followed up in an appropriate clinic.

Conclusion The majority of babies treated for hypothyroidism on the neonatal unit are Guthrie negative. Recognisable patterns of clinical presentations should prompt further screening and early treatment. Babies<32 weeks are more likely to have delayed Guthrie results and/or first TFTs performed. Preterm babies are more likely to have sick/immature thyroid, whereas term babies are more likely to have an underlying syndrome.