单纯性肥胖与皮质醇增多症的实验室鉴别评价

目的对肾上腺皮质功能在肥胖与皮质醇症的鉴别进行研究和评价。方法肥胖 10 4例 ,皮质醇症 15例 ,正常人 47例作皮质醇昼夜节律 ,过夜 1mg地塞米松抑制试验 (ODST)、2 4小时尿游离皮质醇 (UFC)测定 ,皮质醇测定采用放射免疫法。结果 3项试验结果比较 ,肥胖组与正常人组差异无显著意义 (P >0 0 5 ) ,肥胖组与皮质醇症组的差异有极显著意义 (P <0 0 1)。对诊断试验的评价 ,以敏感度、特异度、准确度 ,阳性似然比为主要指标 ,ODST分别为 93 3%、95 2 %、95 0 %、19 44 ;UFC为 10 0 %、94 2 %、95 0 %、17 2 4;夜 12时血浆皮质醇水平 >2 34nmol L时为 10 0 %、94 2 %、95 0 %、17 33。结论 2 4小时UFC排量和ODST具有高敏感度、特异度和高阳性似然比 ,表明ODST和UFC在鉴别中有高度准确性 ,夜 12时血浆皮质醇水平仅在 >2 34nmol L有辅助诊断价值 ,对 3项试验进行综合分析能清楚地将肥胖与皮质醇症区别开来。

Evaluation of laboratory differentiation between simple obesity and hypercortisonism

Objective To study and evaluate the adrenal cortical function in differentiation between simple obesity and hypercortisonism. Methods The plasma cortisol diurnal rhythm, overnight 1mg dexamethasone suppression test (ODST) and urinary free cortisol (UFC) determination were carried out in 104 patients with simple obesity, 15 patients with hypercortisonism and 47 normal sobjects, the cortisol being measured by radioimmunoassay. Results By these three tests, there was no significant difference ( P >0.05) between simple obesity and normal sobjects, while, very significant difference ( P <0.01 ) was occurred between simple obesity and hypercortisonism. Evaluation of the three tests showed that the sensitivity, specificity, accuracy, and positive likelihood ratio were 93.3%, 95 2%,95.0%, 19.44 in ODST; 100%, 94.2%, 95.0%, 17.24 in 24 hour UFC excretion, and 100%, 94.2%, 95.0%, 17.33 in midnight plasma cortisol level >234nmol/L respectively. Conclusion The 24 hour UFC excretion, ODST were valuable, reliable differential diagnostic tests. It was provided to clearly separation simple obesity from hypercortisonism by comprehensive evaluation of three tests.