采血时间对新生儿先天性甲状腺功能减低症筛查结果的影响

The influence of blood collection time on screening results of neonatal congenital hypothyroidism

目的 分析采血时间与新生儿促甲状腺素水平的关系及对新生儿先天性甲状腺功能减低症筛查结果的影响。方法 回顾分析2013年4月至2021年12月筛查的新生儿促甲状腺(TSH)水平,TSH水平检测结果来自于时间分辨荧光分析法的3种检测平台,包括半自动时间分辨荧光分析仪(Wallac 1420)、全自动时间分辨荧光分析仪(Wallac1235)和遗传学筛查系统(GSP)。当TSH水平位于截断值及以上,进行召回复查或进一步诊断,确诊患儿给予规范治疗并定期随访。结果 新生儿TSH水平和初筛阳性率在出生后3~6 d仍然偏高,第4天仍然达到最高,随后急剧下降,在出生后第7天趋于平稳。初筛阳性中患儿占比与新生儿TSH水平和初筛阳性率分布相反,随采血时间的延长有上升的趋势(RR=0.779,P<0.001)。在出生后第4天最低,随后急剧升高,在出生后第12天趋于平稳。结论 新生儿TSH水平受采血时间的影响,可能会导致过多的假阳性和假阴性,建议建立采血时间特异性的TSH截断值。

Objective To analyze the relationship between blood collection time and neonatal thyroid-stimulating hormone(TSH)level and its influence on the screening results of neonatal congenital hypothyroidism(CH).Methods The TSH values of newborns screened from April 2013 to December 2021 were retrospectively analyzed.The TSH results were obtained from three detection platforms of time-resolved fluorescence analysis,including semi-automatic time-resolved fluorescence analyzer(Wallac 1420),fully automatic time-resolved fluorescence analyzer(Wallac 1235)and genetic screening processor(GSP).When the TSH level is higher than the cut-off value,recall for re-examination or further diagnosis is carried out,and the children diagnosed with CH are given standard treatment and regular follow-up.Results Neonatal TSH level and screening positive rate increased from the 3rd to 6th day after birth,reached the highest on the 4th day,then decreased sharply,and stabilized on the 7th day.The distribution of proportion of children with CH in primary positive results was negatively correlated with the neonatal TSH level and primary positive rate(PPR),and there was a rising trend with the blood collection time(RR=0.779,P<0.001).It was the lowest on the 4th day after birth,then increased sharply,and stabilized on the 12th day.Conclusion Neonatal TSH level is affected by blood collection time,which can lead to excessive false positives and false negatives.It is recommended to establish a blood collection time-specific TSH cutoff value.