放宽肝硬化腹水中性多核粒细胞的诊断标准对自发性细菌性腹膜炎的早期诊断价值

Broadening the diagnostic criteria of polymorphonuclear in cirrhotic ascites for the early diagnosis of spontaneous bacterial peritonitis

目的评价放宽肝硬化腹水中性多核粒细胞(polymorphonuclear,PMN)的诊断标准是否可以提高自发性细菌性腹膜炎(spontaneous bacterial peritonitis,SBP)的早期诊断。方法回顾性分析2012年4月至2016年12月首都医科大学附属北京佑安医院根据腹水培养阳性并存在临床可疑SBP症状诊断的SBP患者340例及无任何临床SBP表现且2次腹水培养阴性排除SBP的患者67例,完成腹水培养同时完善腹水常规检查,评价腹水PMN的不同取值对SBP的诊断效率。结果根据腹水PMN计数诊断SBP的诊断效率较高,ROC曲线下面积为0.95(95%CI:0.93~0.97);通过约登指数在ROC曲线上选取最佳cut-off值,cut-off=0.25×10^9L^-1和cut-off=0.10×10^9L^-1有相同的约登指数,均为0.7;当cut-off=0.25×10^9L^-1时的诊断敏感性为74.4%,特异性100%,特异性较高,适合作为确诊指标;当cut-off=0.10×10^9L^-1时的诊断敏感性为93.2%,特异性77.1%,敏感性较高,适合发现早期SBP。对腹水培养阳性的SBP患者,当腹水PMN的cut-off=0.10×10^9L^-1时,假阴性率为6.5%;当腹水PMN的cut-off=0.25×10^9L^-1时,假阴性率为19.1%,经配对χ^2检验,腹水PMN的不同取值对假阴性率的差异有统计学意义(P<0.05)。当腹水PMN的cut-off=0.10×10^9L^-1时,对SBP的敏感度更高,更容易发现早期SBP患者。结论腹水PMN计数是诊断SBP十分有效的诊断指标,当PMN≥0.25×10^9L^-1时可以确诊SBP,但敏感度欠佳,漏诊率高达19.1%;以腹水PMN≥0.10×10^9L^-1诊断SBP可明显降低SBP的漏诊率,可提高早期SBP的诊断效率,同时具有相对较高的特异性。

Objective To evaluate whether broadening the diagnostic criteria of ascites polymorphonuclear (PMN) can improve the early diagnosis of spontaneous bacterial peritonitis (SBP). Methods From Apr.2012 to Dec.2016 in Beijing YouAn Hospital,Capital Medical University,340 patients diagnosed SBP by ascites culture positive combined with suspected SBP symptoms and 67 patients diagnosed no SBP by ascites culture negative combined with no clinical manifestations of SBP were analyzed retrospectively.Routine ascites examination was performed simultaneously with ascites culture,the affection between different values of ascites PMN and the diagnostic efficiency of SBP were evaluated. Results The ascites PMN had a high efficiency in diagnosis of SBP,its area under ROC curve was 0.95 (95% CI :0.93- 0.97 ),the best cut-off value selected on the ROC curve by Jordan index was cut-off was 0.25×10^9 L^-1 or cut-off was 0.10× 10^9 L^-1,which had the same Jordan index (0.7).When cut-off was 0.25×10^9 L^-1,the diagnostic sensitivity was 74.4%,specificity was 100%,it was suitable for diagnostic indicator.When cut-off was 0.10×10^9 L^-1,the diagnostic sensitivity was 93.2%,specificity was 77.1%,it was suitable for early detection of SBP.In ascites culture positive SBP patients,the false negative rate was 19.1% when cut-off was 0.25×10^9 L^-1,but the false negative rate was only 6.5% when cut-off was 0.10×10^9 L^-1,there was statistical difference though χ^2 test ( P <0.05).When ascites PMN cut-off was 0.10×10^9 L^-1,early SBP was more sensitive and easier to be detected. Conclusion Ascites PMN count is a very effective diagnostic index for SBP.When PMN was over 0.25×10^9 L^-1,SBP can be diagnosed,but its sensitivity is not good,the rate of missed diagnosis is 19.1%.Diagnosis of SBP with PMN ≥0.10×10^9 L^-1 can significantly reduce the missed diagnosis rate of SBP and improve the diagnostic efficiency of early SBP,and it has a relatively high specificity.