运动筛查和左旋多巴激发试验在儿童矮小症中的应用

目的评价左旋多巴和运动激发试验对矮小症儿童脑垂体生长激素（GH）分泌的影响。方法对1839例矮小儿童以运动激发为筛查，GH峰值小于5μg／L者再行左旋多巴激发试验。GH检测采用全自动化学发光法，以激发后GH最高值为峰值，峰值大于或等于5μg／L为垂体有应答，小于5μg／L为GH缺乏，大于或等于10μg／L为GH无缺乏，记为激发试验阳性。结果1839例矮小儿童运动激发峰值大于或等于6μg／L者占56．23％，GH无反应者占33．77％，阳性率为24．96％。521例左旋多巴激发无反应者占25．14％，阳性率为40．88％。峰值主要集中在药后30（30．9％）～60min（46．83％），药后120min最少（4．61％，阳性5例）；峰值强度约每30min衰减一半。从整体或有应答来看，左旋多巴峰值强度均高于运动筛查，差异有统计学意义（P〈0.001），但阳性峰值差异无统计学意义。结论运动激发安全、经济，便于门诊筛查，运动筛查结合左旋多巴激发试验可获得较高阳性率。

Application and analysis of the provocation test by exercise screening and levodopa in short stature children

Objective To assess the stimulating effect of levodopa and exercise on pituitary growth hormone （GH） secretion in short stature children. Methods 1 839 cases of short stature children were screened with exercise provocation test, and then the subjects with a GH peak value lower than 5 μg/L underwent levodopa provocation test. Serum GH levels were determined with chemiluminescent immunoassay （CLIA）. The highest GH value after provocation was termed as the peak value. The judging standard was as follows： the peak value was 5 μg/L or above as pituitary gland response; lower than 5 μg/L as GH deficiency; and 10μg/L or above as provocation test positive （no deficiency of GH）. Results Exercise provocation test results of 1 839 cases of short stature children., the short stature children with a GH peak value of 6 μg/L or above accounted for 56.23% GH nonresponders were 33.77%; and the exercise provocation test positive rate was 24.96%. Levodopa provocation test results of 521 cases of short stature children： GH nonresponders accounted for 25.14%, and the levodopa provocation test positive rate was 40.88%. The peak value of levodopa provocation test mostly focused on time period of 30 to 60 min after administration, least at 120 min after administration （5 cases, 4.61%）. About half of the peak value of serum GH was attenuated per 30 minutes. The magnitude of peak value was much higher in levodopa provocation test than that in exercise provocation test from the point of entirety or GH reaponse （P〈0. 001）. Nevertheless, the difference in positive peak value wasn＇t statistically significant between the two tests. Conclusion Exercise provocation test is safe and economic, convenient for screening of growth hormone deficiency （GHD） in out-patient clinic. And higher positive rate may be acquired with combined detection of exercise and levodopa provocation test.