An audit of local practice was undertaken as regards requests for thyroid function tests (TFT) in children aged between birth and 3 months at two local hospitals in South-West England between 2005 and 2008.
A total of 406 tests were performed (2.6 tests per week) over a two-year period at a teaching hospital (70 tests per 1000 live births yearly), with 233 tests (1.5 tests per week) performed over a three-year period at a local district hospital (39 tests per 1000 live births yearly). The highest proportion of all the tests was performed as routine investigation of prolonged neonatal jaundice (64% and 55% respectively). Other common indications were maternal thyroid disorders (5.4% vs 4.7) and suspected neonatal thyroid disorders (3% vs 9%). There was no confirmed diagnosis of infantile thyroid disease.
Available evidence and this audit suggest that too many thyroid function tests are unnecessarily performed in young infants.