Yao Qin, Xu Zuo-Jun, Huang Hui, Tian Xin-Lun, Liu Hong-Rui, Xu Wen-Bing, Chen Yong, Zhu Yuan-Jue, Luo Wei-Ci
Department of Respiratory Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
Zhonghua Jie He He Hu Xi Za Zhi. 2008 Jul;31(7):488-91.
To evaluate the predictive value of single and combined indexes in the diagnosis of sarcoidosis.
Eighty-eight patients suspected of having sarcoidosis were retrospectively investigated. The diagnostic predictive value of lymphocyte percentage and CD4/CD8 ratio in bronchoalveolar lavage (BAL), angiotensin converting enzyme (ACE) and their combination was evaluated by ROC curve method and Bayes' rule.
Final diagnosis of sarcoidosis by biopsy was available in 59 patients (67%), 16 were males (27%), 43 were females (73%), with a mean age of (48 +/- 10) years. The diagnosis of non-sarcoidosis was available in 29 patients (33%), 12 were males (41%), 17 were females (59%), with a mean age of (49 +/- 13) years. The ROC curve area of lymphocyte percentage, CD4/CD8 ratio and ACE were 0.64, 0.74 and 0.69 respectively; CD4/CD8 ratio had the best diagnostic efficiency. The optimized cut-offs of the three single indexes, lymphocyte percentage > or = 30%, CD4/CD8 ratio > or = 4.0 and ACE > or = 40 U/L, were determined by the tangential points and coordinates of the ROC curve. The positive predictive values were 76.7%, 80.4% and 76.8% respectively; CD4/CD8 ratio had the best predictive value. The ROC curve area of the combined CD4/CD8 ratio and ACE was 0.81, and the combination of lymphocyte percentage, CD4/CD8 ratio and ACE was 0.78. They were both higher than those of the respective single indexes. The combination of CD4/CD8 ratio and ACE had the best diagnostic efficiency. On the other hand, it had the best positive predictive value of 90.5% in all the diagnostic indexes.
CD4/CD8 ratio in BAL is still a useful index in the auxiliary diagnosis of sarcoidosis. The combination of CD4/CD8 ratio and ACE can improve the diagnostic efficiency and predictive value of sarcoidosis.
评估单项指标及联合指标在结节病诊断中的预测价值。
对88例疑似结节病患者进行回顾性研究。采用ROC曲线法和贝叶斯法则评估支气管肺泡灌洗（BAL）中淋巴细胞百分比、CD4/CD8比值、血管紧张素转换酶（ACE）及其联合指标的诊断预测价值。
59例患者（67%）经活检最终确诊为结节病，其中男性16例（27%），女性43例（73%），平均年龄（48±10）岁。29例患者（33%）诊断为非结节病，其中男性12例（41%），女性17例（59%），平均年龄（49±13）岁。淋巴细胞百分比、CD4/CD8比值和ACE的ROC曲线面积分别为0.64、0.74和0.69；CD4/CD8比值诊断效率最佳。通过ROC曲线的切点和坐标确定三个单项指标的最佳截断值，淋巴细胞百分比≥30%，CD4/CD8比值≥4.0，ACE≥40 U/L；阳性预测值分别为76.7%、80.4%和76.8%；CD4/CD8比值预测价值最佳。CD4/CD8比值与ACE联合的ROC曲线面积为0.81，淋巴细胞百分比、CD4/CD8比值与ACE联合的为0.78。两者均高于各自单项指标。CD4/CD8比值与ACE联合诊断效率最佳。另一方面，在所有诊断指标中其阳性预测值最佳，为90.5%。
BAL中的CD4/CD8比值仍是结节病辅助诊断的有用指标。CD4/CD8比值与ACE联合可提高结节病的诊断效率和预测价值。
