University of Missouri, Columbia, Mo. 65212, USA.
Respiration. 2012;83(3):198-208. doi: 10.1159/000327200. Epub 2011 May 11.
Eosinophilic pleural effusion (EPE) is defined by an eosinophil count of ≥10% in the pleural fluid and often caused by air or blood in the pleural space. The diagnostic significance of EPEs is still a matter of debate.
The objective of this study was to systematically review the medical literature to evaluate the diagnostic significance of EPEs.
Electronic databases were searched from 1950 to April 2010 to perform a meta-analysis. Data were extracted using standardized forms, and pooled odds ratios with 95% confidence intervals were calculated. A logistic regression analysis was also performed to evaluate the association between the pleural eosinophil counts and the likelihood of underlying causes of EPEs.
We identified a total of 687 cases of EPE. The most common cause of EPEs was malignancy (26%) followed by idiopathic (25%) and parapneumonic (13%) effusions. The likelihood of malignancy or tuberculosis was somehow lower in EPEs than in non-EPEs, but the differences were not statistically significant. The prevalence of malignancy was significantly lower in the group of patients that required a pathologic confirmation (21 vs. 30%; p = 0.01). The likelihood of malignancy was inversely correlated with the pleural fluid eosinophil counts. The likelihood of idiopathic effusion was significantly higher in EPEs than in non-EPEs.
Malignancy was the most common cause of EPEs. EPEs appeared to be a negative predictor of malignancy when a pleural fluid eosinophil count was extremely high. EPEs were more likely to be idiopathic as compared with non-EPEs.
嗜酸粒细胞性胸腔积液（EPE）定义为胸腔积液中嗜酸粒细胞计数≥10%，通常由胸腔内空气或血液引起。EPE 的诊断意义仍存在争议。
本研究旨在系统回顾医学文献，评估 EPE 的诊断意义。
从 1950 年到 2010 年 4 月，我们通过电子数据库进行了荟萃分析。使用标准化表格提取数据，并计算合并优势比及其 95%置信区间。还进行了 logistic 回归分析，以评估胸腔嗜酸粒细胞计数与 EPE 潜在病因的可能性之间的关联。
我们共确定了 687 例 EPE。EPE 最常见的病因是恶性肿瘤（26%），其次是特发性（25%）和类肺炎性（13%）胸腔积液。EPE 患者发生恶性肿瘤或结核的可能性低于非 EPE 患者，但差异无统计学意义。需要病理证实的患者组中恶性肿瘤的发生率明显较低（21%比 30%；p=0.01）。恶性肿瘤的可能性与胸腔积液嗜酸粒细胞计数呈负相关。特发性胸腔积液在 EPE 患者中的发生率明显高于非 EPE 患者。
恶性肿瘤是 EPE 最常见的病因。当胸腔积液嗜酸粒细胞计数极高时，EPE 似乎是恶性肿瘤的阴性预测指标。与非 EPE 相比，EPE 更可能是特发性的。
