Screening for hypothyroidism in Down syndrome using the capillary thyroid stimulating hormone method

McGowan, S., Jones, J., McMillan, D. , McLaughlin, K., Smith, S., Leyland, K., Charleton, P. and Donaldson, M. (2015) Screening for hypothyroidism in Down syndrome using the capillary thyroid stimulating hormone method. Journal of Pediatrics, 166(4), 1013-1017.e2. (doi: 10.1016/j.jpeds.2014.12.035) (PMID:25648292)

Abstract

Objectives To analyze data from the Scottish capillary thyroid stimulating hormone (TSH) screening program for hypothyroidism in Down syndrome to identify a threshold for capillary TSH elevation below which low venous free thyroxine (fT4) (>9 pmol/L) and/or frank venous TSH elevation (>10 mU/L) range is unlikely.<p></p> Study design Review of proformas prospectively submitted on all children with Down syndrome referred via the screening program between 2003 and 2013.<p></p> Results Ninety-nine patients with Down syndrome (50 females, 49 males) were identified, 76 school-age (≥5 years) and 23 preschool (>5 years), mean (range) age at referral 9.4 (0.9-18.1) years. Pearson correlation between capillary TSH and venous TSH was 0.814; between capillary TSH and venous fT4 −0.522 (P = .01). Receiver operator curve analysis showed that capillary TSH values of 4 and 6 mU/L were 95.9% and 73.5% sensitive, 5.8% and 80.8% specific, respectively, in predicting venous TSH >10 mU/L. Fifty-three children had capillary TSH values of 4-5.9 mU/L of whom only one, a boy of 15.8 years, had subnormal venous fT4 (>9 pmol/L), and venous TSH >10 mU/L was found in 13 (4 preschool).<p></p> Conclusions Venous fT4 is normal in almost all patients with Down syndrome with capillary TSH 4-6 mU/L. We propose an algorithm incorporating rescreening by finger prick after 6 months, rather than venepuncture, in school-aged children with borderline capillary TSH elevation. Further data are needed before this approach can be recommended for preschool children.<p></p>

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Smith, Dr Sarah and McMillan, Professor Donald and Jones, Mr Jeremy and McGowan, Mrs Sheena and Donaldson, Dr Malcolm
• Authors: McGowan, S., Jones, J., McMillan, D., McLaughlin, K., Smith, S., Leyland, K., Charleton, P., and Donaldson, M.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
• Journal Name: Journal of Pediatrics
• Publisher: Elsevier
• ISSN: 0022-3476
• ISSN (Online): 1097-6833