新生儿先天性肾上腺皮质增生症筛查分析

The analysis on neonatal screening for congenital adrenal hyperplasia

目的探讨新生儿先天性肾上腺皮质增生症（CAH）筛查情况，为CAH的早期筛查、确诊和治疗提供依据。方法选择柳州市新生儿疾病筛查中心2010年9月至2012年12月进行CAH筛查的新生儿，采用时间分辨荧光免疫分析方法检测滤纸片17．羟孕酮（17-OHP）浓度，通过数据分析确立实验室筛查的切值。结果研究期间共筛查46592例新生儿，初筛阳性304例，确诊1例CAH。同一胎龄组中17-OHP浓度随体重增加而降低，同一体重组中早产儿17-OHP浓度大于足月儿，差异均有统计学意义（P〈0．05）。3327例早产儿97．5^th和99^th分位数值分别为40．1nmol／L和57．3nmoL／L，体重〈2500g早产儿切值定为40．0nmo]／L，体重≥2500g定为30．0nmol／L；足月儿中，体重〈2500g者97．5^th和99^th分位数值分别为20．9nmol／L和27．5nmol／L，体重2500～4000g 97．5^th和99^th分位数值分别为16．8nmol／L和21．1nmol／L，但初筛17-OHP浓度分布显示99．8％的新生儿筛查结果分布在O．0～30．0nmol／L，所以，足月儿无论体重大小17-OHP实验室筛查切值均定为30．0nmoL／L。结论确立17．OHP筛查切值，规范实验室管理，具有临床意义。

Objective To evaluate neonatal screening test for congenital adrenal hyperplasia （CAH） to facilitate early screening, prompt diagnosis and treatment. Methods Neonates were screened for CAH in Liuzhou newborn screening center from September 2010 to December 2012 in the study. 17-OHP on filter paper were analyzed using time-resolved fluoroimmunoassay （TRFIA）, and the cutoff values of 17-OHP were determined through data analysis. Results Total of 304 neonates showed positive results on initial screening out of a total of 46 592 newborns. The diagnosis was confirmed in only one neonate subsequently. In neonates with the same gestational age, 17-OHP levels decreased as birth-weight increasing, and in the group with the same birth-weight, 17-OHP levels were higher in premature neonates than that of full-term neonates, the differences were statistically significant （ P 〈 0. 05 ）. The 97.5^th and 99^th percentiles of 17-OHP levels were 40. 1nmol/L and 57.3 nmol/L in the 3327 premature newborns, respectively. The 17-OHP cutoff values were 40. Onmol/L for birth-weight 〈 2500 g, and 30. 0 nmol/L for birth-weight ≥2500 g. Of the full-term newborns, the 97.5^th and 99^th percentiles were 20. 9 nmol/L and 27.5 nmol/L respectively for birth-weight 〈 2500 g, 16.8nmol/L and 21.1 nmol/L for birth-weight 2500 -4000 g. However, 17-OHP distribution curve showed that 99. 8% of neonatal screening results scattered between 0. 0 and 30.0 nmol/L, so 17-OHP cutoff value was determined as 30. 0 nmol/L for full-term newborns regardless of birth-weight. Conclusions Determining 17-OHP cutoff values could standardize both clinical diagnosis and laboratory management.