Practice Variance in Thyroid Screening of Youth with Type 1 Diabetes Mellitus.

BACKGROUND: Variance between current American Diabetes Association (ADA) and International Society for Pediatric and Adolescent Diabetes (ISPAD) guidelines and in clinical practice exists for the use of thyroid antibody and thyroid function screening in pediatric patients with new-onset type 1 diabetes (T1D).

METHODS: North American Pediatric Endocrine Society (PES) members were surveyed regarding their thyroid screening practices of euthyroid youth with T1D. An institutional analysis of the ability of antithyroid peroxidase (aTPO) and antithyroglobulin antibodies (aTG) to predict the subsequent use of levothyroxine was performed.

RESULTS: Forty-eight percent of 374 survey respondents tested both aTPO and aTG at diagnosis of T1D, but 35% performed no baseline antibody testing. If antibodies were positive, 89% of the respondents would perform annual thyroid function testing, but if antibodies were negative, 62% would follow thyroid function annually and 29% biannually. Institutionally, aTPO had significantly greater sensitivity (p = 0.04) but lower specificity (p = 0.008) than aTG for predicting the use of levothyroxine.

CONCLUSIONS: Variance exists among North American PES members regarding thyroid disease screening for pediatric patients diagnosed with T1D, and this appears to reflect differences between ADA and ISPAD guidelines. A prospective multicenter observational study which shares electronic medical record data and compares aTPO and TSH as primary screening tests may allow for more uniform guidelines and address the possibility of using TSH alone.