盐酸对24小时尿游离皮质醇测定的影响

Influence of Hydrochloric Acid to the Measurement of Free Cortisol in 24-hour Urine

目的研究尿标本中防腐剂盐酸对24h尿游离皮质醇测定的影响。方法收集2008年7月2009年1月正常人、库欣病患者及其他疾病患者的24h尿液,混匀后,一部分浓盐酸防腐,一部分未加盐酸直接保存。电化学发光免疫分析法同步检测尿游离皮质醇浓度。结果经配对t检验加浓盐酸后的24h尿游离皮质醇测值均高于未加酸者,比较有统计学意义(P<0.05)。加盐酸和未加盐酸所测尿游离皮质醇二者之间具有较好的相关性,相关系数r=0.97,P<0.05。结论浓盐酸防腐的标本24h尿游离皮质醇测值较未加酸保存的标本高。因此,为了得到相对准确的值,更好地反映肾上腺实际分泌情况,测定24h尿游离皮质醇的标本不应使用盐酸防腐。

Objective This article discussed the influence of hydrochloric acid in the urine to the measurement of 24-hour urinary free cortisol. Methods 24-hour urine specimens of normal people,patients clinically diagnosed Cushing＇s syndrome and patients with other disease were collected,and 24 hour urine volumes were recorded. After vigorous shaking,part of the urine is preserved by hydrochloric acid,the rest is preserved without hydrochloric acid. Allurine specimens were assayed synchronously by Electro Chemiluminescence Immuno Assay（ECLIA）. Result The concentration of the 24-hour urinary free cortisol preserved by hydrochloric acid is much higher than that preserved without hydrochloric acid. Conclusion In order to obtain an accurate result the 24-hour urine specimens of measuring 24-hour urinary free cortisol should not be preserved by hydrochloric acid.