生长激素缺乏症生化检测综合分析

Evaluation of the diagnostic value of biochemical tests in children with growth hormone deficiency

目的以临床诊断作为矮小症患儿(可疑GHD)诊断标准,评估生长激素激发试验、胰岛素样生长因子Ⅰ(IGFⅠ)及IGF结合蛋白3(IGFBP3)对GHD的诊断价值。方法放免方法检测84例可疑GHD患者及63例非GHD患者GH峰值、IGFⅠ及IGFBP3,运用ROC曲线方法选定各生化检测的最佳截定值,并计算各最佳截定值的敏感性(sensitivity,S)、特异性(specificity,Sp)及诊断有效率(diagnosticefficiency,DEf)。结果ROC曲线显示GH激发试验GH峰值7.65μg/L为最佳截定值,DEf达84.4%,S为75.9%,Sp达94.9%;IGFⅠSDS最佳截定值为-1.85,S为70.2%、Sp为83.1%、DEf为70.2%;IGFBP3SDS最佳截定值为-1.55,比传统-2SD高,DEf为64.3%,Sp较高(89.8%),但S仅为45.8%。联合使用上述3种测定有较佳的DEf(91.2%),S(89.3%)和Sp(93.7%)。结论GH激发试验如选取一个好的截定值(本研究为GH峰值7.65μg/L),则该试验对GHD具有较高诊断价值;单个IGFⅠ检测则逊于GH激发试验;IGFBP3单独诊断GHD价值不大。三者联合使用诊断率及准确率皆很高,最具诊断价值。

Objective To evaluate the diagnostic value of biochemical tests（GH stimulation tests, IGF-Ⅰ and IGFBP-3） in short children suspected with growth hormone deficiency （GHD）. Methods The patients were divided into 2 groups ： GHD group including 84 suspected GHD short children aged （ 10.8±1.9 ） years, in whom diagnosis of GHD was based on a medical history associated with typical phenotypic feature, and non-GHD group including 63 short children aged （10.6±2.7 ）years, in whom GHD was not suspected. The receiver operating characteristic （ROC） plot analysis was used and sensitivity （S） , specificity （Sp） and diagnostic efficiency （DEf） of cut-off point were calculated. Results The ROC plot showed that the cut-off point for GH stimulation ： （ 1 ） The peak value of GH was 7.65ng/ml with sensitivity （S） 75.9%, specificity （Sp） 94.9%, diagnostic efficiency （ DEf）, 84.4% ; （2） IGF-Ⅰ SDS was -1.85 with S 70.2%, Sp 83.1%, DEf, 70.2% ; （3） The IGFBP-3 SDS was -1.55 with S 45.8% , Sp 89.8% , DEf, 64.3%. The joint use of these 3 laboratory assays showed higher S （ 89.3% ） , Sp（93.7% ） , and Def（ 91.2% ）. Conclusions Our findings support the need to define the best cut-off line for each laboratory assay for diagnosing GHD. Pharmaceutical stimulation test is more valuable than measurement of serum IGF-Ⅰ alone. Serum IGFBP-3 does not significantly contribute to the diagnosis of GHD. The joint use of these 3 laboratory assays seems to be most effective for GHD diagnosis with high value of DEf, S, and Sp.