BLOOD SPOT TSH IN CHILEAN NEONATES: IS A CUT-OFF VALUE OF 15 MU/L APPROPRIATE?

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 622-631-Pediatric Endocrinology: Thyroid
Clinical
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-629
Francisca Grob*1, Marcela Lagos2, Helena Poggi2, Ligia Valdivia2, Diego Ignacio Carillo2 and Alejandro Martínez-Aguayo1
1Pontificia Universidad Católica de Chile, Santiago, Chile, 2Pontificia Universidad Católica de Chile, Santiago de Chile, Chile
Introduction: The selection of an appropriate blood spot thyrotropin (ns-TSH) threshold value for screening newborns for hypothyroidism is still under discussion. In Chile, a cuff-off value of 15 mU/L for ns-TSH is currently recommended when using the DELFIA system.

Objective: To describe ns-TSH values in Chilean neonates.

Subjects and methods: We analyzed data from 2356 neonates, born in the Pontificia Universidad Católica de Chile Hospital between July 2010 and April 2011. We did not exclude newborns presenting comorbidities or admitted to intensive care unit. ns-TSH levels were determined with the DELFIA system, and results are expressed as median, 3rd and 97thcentiles. 

Results: Mean gestational age was 38.07 ± 2.1 weeks and mean birth weight was 3216.09 ± 583.4 g. The median ns-TSH was 2.97 mU/L [0.58 and 10.95 mU/L]. The percentage of neonates with ns-TSH levels >15 mU/L was 0.59 %, and 3.23% presented ns-TSH between 10 and 15 mU/L. Also, 0.33% had ns-TSH < 0.10 mU/L. 

Conclusion: The 97 percentile value of this sample was lower than the cutoff of neonatal TSH currently used in Chile. Regarding these results, we recommend the follow up newborns with ns-TSH between 10 and 15 mIU/L and to evaluate costs and benefits of lowering the cut-off from 15 to 10 mIU/L. Newborns with TSH < 0.58 mIU/L should be evaluated.

Nothing to Disclose: FG, ML, HP, LV, DIC, AM

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm