二代基因测序技术联合半乳甘露聚糖检测对重症肺炎合并真菌感染的诊断价值

目的 探究二代基因测序技术（NGS）联合半乳甘露聚糖（GM）检测对重症肺炎合并真菌感染的诊断价值。方法 选取2020年3月—2023年3月大庆龙南医院急诊重症监护室收治的重症肺炎患者148例。收集支气管肺泡灌洗液行病原微生物培养及肺泡灌洗液NGS检测，同期行血清GM检测。以病原微生物培养为金标准，分析血清GM及肺泡灌洗液NGS诊断重症肺炎合并真菌感染的敏感性、特异性，评估血清GM检测、肺泡灌洗液NGS检测单独及联合诊断重症肺炎合并真菌感染结果与病原微生物培养结果的一致性。结果 148例重症肺炎中合并真菌感染30例，其中肺孢子菌10例、白色念珠菌8例、曲霉菌7例、根霉菌1例、肺孢子菌感染合并白色念珠菌3例、肺孢子菌感染合并鲍曼不动杆菌1例。血清GM检测结果显示，阳性28例，阴性120例，与病原学培养诊断真菌感染的Kappa值为0.700。肺泡灌洗液NGS诊断结果显示，阳性34例，阴性114例，与病原学培养诊断真菌感染的Kappa值为0.841。血清GM联合肺泡灌洗液NGS诊断结果显示，阳性30例，阴性118例，病原学培养诊断真菌感染的Kappa值为0.916。血清GM、肺泡灌洗液NGS单独及联合诊断重症肺炎合并真菌感染的敏感性分别为73.3%（95% CI：0.538，0.870）、93.3%（95% CI：0.765，0.988）、93.3%（95% CI：0.765，0.988），特异性分别为94.9%（95%CI：0.888，0.979）、94.9%（95% CI：0.889，0.979）、98.3%（95% CI：0.934，0.997），曲线下面积分别为0.841、0.941和0.958。结论 血清GM联合肺泡灌洗液NGS诊断重症肺炎合并真菌感染，在肺孢子菌、白色念珠菌及曲霉菌等常见菌种中的诊断效能良好。

Diagnostic value of next-generation sequencing combined with serum galactomannan antigen test for severe pneumonia complicating fungal infection

Objective To investigate the diagnostic value of next-generation sequencing (NGS) combined with serum galactomannan (GM) antigen test for severe pneumonia complicating fungal infection.Methods Between March 2020 and March 2023, a total of 148 patients with severe pneumonia admitted to the Emergency Intensive Care Unit of Daqing Longnan Hospital were included in this study. Bronchoalveolar lavage fluid was collected and subjected to microbial culture and NGS analysis. The serum GM antigen test was performed concurrently. With the results of microbial culture as the gold standard, the sensitivity and specificity of the serum GM antigen test and NGS on bronchoalveolar lavage fluid for diagnosing fungal infections in severe pneumonia were analyzed. The concordance of the serum GM antigen test and NGS on bronchoalveolar lavage fluid alone and their combination with the microbial culture was evaluated.Results Among 148 cases of severe pneumonia, 30 cases were complicated with fungal infections, including 10 cases of Pneumocystis, 8 cases of Candida albicans, 7 cases of Aspergillus, 1 case of Rhizopus, 3 cases of Pneumocystis with Candida albicans, and 1 case of Pneumocystis with Acinetobacter baumannii. The serum GM antigen test demonstrated that 28 cases were positive and 120 cases were negative, with a Kappa value of 0.700 for diagnosing fungal infections in comparison with the microbial culture. The NGS on bronchoalveolar lavage fluid showed that 34 cases were positive and 114 cases were negative, with a Kappa value of 0.841 for diagnosing fungal infections in comparison with the microbial culture. The combined detection via the serum GM antigen test and NGS on bronchoalveolar lavage fluid revealed that 30 cases were positive and 118 cases were negative, with a Kappa value of 0.916 for diagnosing fungal infections in comparison with the microbial culture. The sensitivities of the serum GM antigen test and NGS on bronchoalveolar lavage fluid alone and their combination for the diagnosis of severe pneumonia with fungal infection were 73.3% (95% CI: 0.538, 0.870), 93.3% (95% CI: 0.765, 0.988) and 93.3% (95% CI: 0.765, 0.988), with the specificities being 94.9% (95% CI: 0.888, 0.979), 94.9% (95% CI: 0.889, 0.979) and 98.3% (95% CI: 0.934, 0.997), and the areas under the curves (AUCs) being 0.841, 0.941 and 0.958.Conclusions The combination of the serum GM antigen test and NGS on bronchoalveolar lavage fluid exhibits great diagnostic efficacy for fungal infections in severe pneumonia, especially for common fungal species such as Pneumocystis, Candida albicans, and Aspergillus.