Efficacy of morning serum LH combined with IGF–1 on pubertal initiation in children

Abstract

Objective To explore the screening cut-off point and screening efficacy of morning serum LH combined with IGF–1 levels on puberty initiation to provide the basis for developing the gnrh stimulation test reasonably and promoting the systematic management of children and adolescence.

Methods A retrospective study was conducted to select 1 724 children aged 8–13 years who took physical examination and were identified of breast development (between grade 2 and grade 3) or increased testicular volume (4.00–10.00 mL) in Child Health Department of Wuhan Children’s Hospital during January 1st 2019 and December 31th 2021, and gonadotropin releasing hormone (GnRH) stimulation test was performed in endocrinology department ward in the same period. Doppler ultrasound was used to determine gonadal volume, and GnRH stimulation test was conducted to determine the puberty initiation in children. The ROC curve was utilized to determine the screening cut-off points of morning serum LH and IGF–1 on puberty initiation, and the reliability and validity of the cut-off points were all tested.

Results The testicular volume was (4.88±2.19) mL in boys, and 75.5% was classified as initiation of gonadal growth. Whereas the ovaries volume was (1.78±0.65) mL in girls, and 91.39% classified as initiation of gonadal growth. The results of the GnRH stimulation test showed that among boys and girls, the medians LH peak were 13.22 and 21.79 IU/L, and the median LH/FSH peak ratios were 2.13 and 1.87. As a result, 597 boys and 864 girls were diagnosed as puberty initiation. Screening efficacy analysis indicated that the cut-off point of morning serum LH on puberty initiation were 0.23 IU/L in male ( Kappa = 0.60) and 0.22 IU/L in female ( Kappa = 0.66), and IGF–1 cut-off point were 187.00 IU/L in male ( Kappa = 0.45) and 178.00 IU/L in female ( Kappa = 0.46). High sensitivity and specificity and better screening efficacy ( Kappa = 0.60, 0.64) on single-item screening of morning blood LH in boys and tandem screening of LH and IGF–1 in girls.

Conclusion Morning serum LH and IGF–1 are good predictors on puberty initiation. GnRH stimulation test should be carried out to determine the puberty initiation when morning serum LH reaches 0. 23 IU/L in boys, morning serum LH reaches 0.22 IU/L and IGF–1 reaches 178.00 IU/L in girls.

Abstract

【摘要】 目的 探索晨血促黄体生成素 (LH) 和胰岛素样生长因子 (IGF–1) 水平对青春期启动的筛査切值点及筛査效能, 为合理开展 GnRH 刺激试验、促进儿童青春期系统管理提供依据。 方法 采用回顾调査的方法, 选取 2019 年 1 月 1 日至 2021 年 12 月 31 日在武汉儿童医院儿童保健科体检、乳房发育在 B2~B3 期或睾丸体积在 4.00~10.00 mL、同期在内分泌病 房进行 GnRH 刺激试验的 1 724 名 8~13 岁儿童为研究对象。采用彩色多普勒超声测定性腺容积, 采用 GnRH 刺激试验判 断儿童青春期启动状况, 采用 ROC 曲线确定晨血 LH、IGF–1 筛査切值点, 并进行信度和效度检验。 结果 男童睾丸容积 (4.88±2.19) mL, 性腺启动者检出率 75.5%; 女童卵巢容积 (1.78±0.65) mL, 性腺启动者检出率 91.39%。GnRH 刺激试验显 示, 男、女童 LH 峰值中位数为 13.22, 21.79 IU/L, LH/FSH 峰值比中位数为 2.13, 1.87, 青春期启动者 597, 864 例。男、女童 晨血 LH 对青春期启动的筛査切值点为 0.23 ( Kappa = 0.60) 和 0.22 IU/L ( Kappa = 0.66), IGF–1 切值点为 187.00 ( Kappa =0.45) 和 178.00 IU/L ( Kappa = 0.46)。男童晨血 LH 单项筛査、女童晨血 LH 与 IGF–1 串联筛査的灵敏度和特异度均较髙, 筛査效能较好 ( Kappa 指数分别为 0.60, 0.64)。 结论 晨血 LH、IGF–1 是儿童青春期启动的良好预测指标, 当男童晨血 LH 达 0.23 IU/L、女童晨血 LH 达 0.22 IU/L 且 IGF–1 达 178.00 IU/L 时, 应进行 GnRH 刺激试验明确青春期启动状况。