Objective: To evaluate the application value of metagenomic next-generation sequencing (mNGS) in the diagnosis and treatment of pulmonary infection in immunocompromised patients. Methods: A total of 78 patients with immunocompromised pulmonary infection [55 males and 23 females, aged (50.3±16.9) years] and 61 patients with non-immunocompromised pulmonary infection [42 males and 19 females, aged (63.6±15.9) years] in the Intensive Care Unit of the First Medical Center of College of the Pulmonary & Critical Care Medicine, Chinese PLA General Hospital from November 2018 to May 2022 were retrospectively selected. Patients in both groups received bronchoalveolar lavage fluid (BALF) mNGS and conventional microbiological tests (CMTs) while clinically diagnosed with pulmonary infection. The diagnostic positive rate, pathogen detection rate and clinical coincidence rate of the two methods were compared. At the same time, the difference of adjustment rate of anti-infective treatment strategy based on the results of mNGS detection was compared between the two groups. Results: The positive rates of mNGS in patients with pulmonary infection were 94.9% (74/78) and 82.0% (50/61) in the immunocompromised group and the non-immunocompromised group, respectively. The positive rates of CMTs in patients with pulmonary infection were 64.1% (50/78) and 75.4% (46/61) in the immunocompromised group and the non-immunocompromised group, respectively. The positive rates of mNGS and CMTs in patients with pulmonary infection in immunocompromised group showed a statistically significant difference (P<0.001). The detection rates of mNGS in the immunocompromised group for pneumocystis jirovecii and cytomegalovirus were 41.0% (32/78) and 37.2% (29/78), respectively, and the detection rates of Klebsiella pneumoniae, chlamydia psittaci and Legionella pneumophila were 16.4% (10/61), 9.8% (6/61) and 8.2% (5/61) in the non-immunocompromised patients, respectively, which were higher than those of CMTs [1.3% (1/78), 7.7% (6/78), 4.9% (3/61), 0 and 0] (all P<0.05). In the immunocompromised group, the clinical coincidence rates of mNGS and CMTs and were 89.7% (70/78) and 43.6% (34/78), respectively, with a statistically significant difference (P<0.001). In the non-immunocompromised group, the clinical coincidence rates of mNGS and CMTs were 83.6% (51/61) and 62.3% (38/61), with a statistically significant difference (P=0.008). In the immunocompromised group, according to the results of the etiology of mNGS, the adjustment rate of anti-infection treatment strategy was 87.2% (68/78), while in the non-immunocompromised group, the adjustment rate of anti-infective treatment strategy was 60.7% (37/61), with a statistically significant difference (P<0.001). Conclusion: In patients with immunocompromised pulmonary infection, mNGS has more advantages than CMTs in diagnostic positive rate, diagnosis rate of mixed infection, pathogen detection rate and guidance of anti-infection treatment strategy adjustment, which is worthy of clinical promotion and application.
目的： 评价宏基因组高通量测序（mNGS）在免疫缺陷患者肺部感染诊断与治疗中的应用价值。 方法： 回顾性选取2018年11月至2022年5月在解放军总医院呼吸与危重症医学部第一医学中心重症监护室的78例免疫缺陷肺部感染患者［男55例，女23例，年龄（50.3±16.9）岁］和61例非免疫缺陷肺部感染患者［男42例，女19例，年龄（63.6±15.9）岁］。两组患者在临床诊断为肺部感染的同时，均行支气管肺泡灌洗液（BALF）的mNGS及常规微生物学检测（CMTs）。比较两种检测方法的诊断阳性率、病原体检出率以及与临床符合率的差异。同时比较两组患者根据mNGS检测结果抗感染治疗策略调整率的差异。 结果： 免疫缺陷组与非免疫缺陷组肺部感染患者mNGS诊断阳性率分别为94.9%（74/78）和82.0%（50/61），CMTs诊断阳性率分别为64.1%（50/78）和75.4%（46/61），免疫缺陷组mNGS与CMTs诊断阳性率差异有统计学意义（P<0.001）。mNGS在免疫缺陷组中耶氏肺孢子菌、巨细胞病毒的检出率分别为41.0%（32/78）、37.2%（29/78），在非免疫缺陷组中肺炎克雷伯菌、鹦鹉热衣原体、嗜肺军团菌的检出率分别为16.4%（10/61）、9.8%（6/61）、8.2%（5/61），均高于CMTs的1.3%（1/78）、7.7%（6/78）、4.9%（3/61）、0、0（均P<0.05）。免疫缺陷组mNGS、CMTs与临床符合率分别为89.7%（70/78）、43.6%（34/78），差异有统计学意义（P<0.001）。非免疫缺陷组mNGS、CMTs与临床符合率分别为83.6%（51/61）、62.3%（38/61），差异有统计学意义（P=0.008）。免疫缺陷组根据mNGS病原学结果，抗感染治疗策略调整率为87.2%（68/78），非免疫缺陷组抗感染治疗策略调整率为60.7%（37/61），差异有统计学意义（P<0.001）。 结论： 在免疫缺陷肺部感染患者中，与CMTs相比，mNGS在诊断阳性率、混合型感染诊断率、病原体检出率及指导抗感染治疗策略的调整方面更具优势，值得临床推广应用。.