根据孕周调整先天性肾上腺皮质增生症筛查切值的初步研究

Pilot study on the adjustment of the cut-off value for congenital adrenal hyperplasia screening according to gestational age

目的探讨孕周与性别对新生儿足跟血17-羟孕酮浓度的影响,建立切合新疆地区实际情况的筛查切值。方法选择2019年8月至2020年12月于我中心进行先天性肾上腺皮质增生症筛查的新生儿足跟血17-羟孕酮浓度数据进行回顾性分析。将新生儿按照性别、孕周进行分组并比较各组间17-羟孕酮浓度的差异,采用百分位数法优化设定筛查切值。结果2019年8月至2020年12月共9552例新生儿参加先天性肾上腺皮质增生症筛查,其中男性4969人,女性4583人;早产儿901人,足月儿8651人。分析显示男性新生儿的17-羟孕酮浓度高于女性新生儿,差异具有极显著性(P<0.01);早产儿的17-羟孕酮的浓度高于足月儿,差异具有极显著性(P<0.01)。最终根据孕周分组分别设定筛查切值,早产儿切值设定为30nmol/L,足月儿切值设定为12nmol/L。采用新的切值后,筛查阳性率从2.59%下降至0.96%,差异具有显著性(P<0.05)。结论与足月儿相比,早产儿17-羟孕酮浓度高,易导致筛查假阳性,应根据孕周分别设定切值可提高检验效能。

Objective To explore the influence of gestational age and gender on the concentration of 17-hydroxyprogesterone in neonatal heel blood,and to establish the screening cut-off value suitable for the actual situation in Xinjiang.Methods The 17-hydroxyprogesterone(17-OHP)concentration data of neonates screened for congenital adrenal hyperplasia(CAH)in our center from August 2019 to December 2020 were retrospectively analyzed.The newborns were divided into groups according to the gestational age of sex and the difference of 17-hydroxyprogesterone concentration among the groups was compared.The screening cut-off value was set by percentile method.Results From August 2019 to December 2020,a total of 9552 newborns were screened for CAH,including 4969 males and 4583 females,901 premature infants and 8651 full-term infants.The analysis showed that 17-OHP concentration in male neonates was higher than that in female neonates,and the difference was very significant(P<0.01).The concentration of 17-OHP in preterm infants was higher than that in term infants,and the difference was very significant(P<0.01).Finally,screening cut-off values were set according to gestational age.The cut-off values for premature infants were set as 30 nmol/L,and those for full-term infants were set as 12 nmol/L.The positive rate of screening with the new cut-off value decreased from 2.59%to 0.96%,and the difference was significant(P<0.05).Conclusion The concentration of 17-OHP in preterm infants is higher than that in term infants,which is easy to lead to false positive screening.The cut-off values should be set according to the gestational age to improve the screening efficiency.