Abstract: 【Objective】 To investigate the changes and clinical significance of body mass index (BMI), serum insulin-like growth factor 1 (IGF-1) and leptin in the female children with idiopathic central precocious puberty (ICPP) and simple premature thelarche (SPT). 【Methods】 BMI, serum IGF-1 and leptin were detected in 28 female children with ICPP and 32 cases with SPT. 26 children with normal puberty and 30 underdeveloped children were as control group. The correlations of BMI, serum IGF-1 and leptin were analyzed. The diagnostic value of IGF-1 and leptin was evaluated in the patient with ICPP. 【Results】 The serum levels of IGF-1 and leptin in the patients with ICPP were higher than those of children with SPT and the underdeveloped children, which there was statistical significance (P<0.01). There was no statistical significance between ICPP and the normal puberty groups (P>0.05). Serum level of IGF-1 and leptin were both positively correlated with BMI (r=0.67,0.71,P<0.01) in the patients with ICPP, and there were also positive correlations between IGF-1, leptin and BMI (r=0.63,0.68,P<0.01) in the children with normal puberty. There were no correlations between IGF-1, leptin and BMI in the children with SPT and underdeveloped children. The sensitivity, specificity and positive predictive value were 95.4%, 96.3% and 95.6% respectively for the diagnosis of ICPP when the serum IGF-1 was above 319.47 ng/mL. The sensitivity, specificity and positive predictive value were 96.5%, 95.7% and 94.8% respectively for the diagnosis of ICPP when the serum leptin was above 6.32 ng/mL. 【Conclusions】 The serum level of IGF-1 and leptin are useful for differential diagnosis of ICPP with SPT and can be as reference factors for the diagnosis of ICPP. IGF-1 and leptin are probably the factors in the activating of the GnRH pulse secretion.

Key words: precocious puberty, insulin-like growth factor 1, leptin, simple premature thelarche

摘要： 【目的】 探讨特发性中枢性性早熟(idiopathic central precocious puberty, ICPP)女童、单纯性乳房早发育(simple premature thelarche, SPT)患儿血清胰岛素样生长因子-1(IGF-1)、瘦素(leptin)、体质指数(body mass index, BMI)的变化及临床意义。 【方法】 测定28例ICPP及32例SPT女童BMI、血清IGF-1和leptin的水平,并以26名正常青春发育期女童及30名未发育女童作为对照,观察BMI及血清IGF-1、leptin水平的相互关系;以IGF-1及leptin为诊断指标,对ICPP进行诊断试验评价。 【结果】 ICPP组女童血清IGF-1及leptin水平均明显高于SPT及未发育女童,差异有统计学意义(P<0.01),而与正常青春发育女童差异无统计学意义(P>0.05)。ICPP组女童IGF-1及leptin水平均与BMI呈正相关(r=0.67,0.71,P<0.01);正常青春发育组女童IGF-1及leptin水平均与BMI亦呈正相关(r=0.63、0.68,P<0.01);SPT组、未发育组女童IGF-1及leptin水平均与BMI无相关关系(P>0.05)。IGF-1>319.47 ng/mL对诊断ICPP的灵敏度、特异度、阳性预测值分别为95.4％、96.3％、95.6％;leptin>6.32 ng/mL对诊断ICPP的灵敏度、特异度、阳性预测值分别为96.5％,95.7％,94.8％。 【结论】 IGF-1和leptin水平的测定可作为ICPP诊断的参考指标,对鉴别ICPP与SPT具有重要临床意义;同时,IGF-1和Leptin可能是激活GnRH脉冲分泌的相关代谢因子。

关键词: 性早熟, 胰岛素样生长因子-1, 瘦素, 单纯性乳房早发育