Clinical Application and Evaluation of Metagenomic Next-Generation Sequencing in Pulmonary Infection with Pleural Effusion

PURPOSE: Metagenomic next-generation sequencing (mNGS) is a novel technique of pathogens detection that plays an increasingly important role in clinical practice. In this study, we explored the application value of mNGS in pulmonary infection combined with pleural effusion applied to samples of pleural effusion fluid. PATIENTS AND METHODS: We reviewed 80 cases of pulmonary infection with pleural effusion between August 2020 and October 2021. Among them, 40 patients were placed in the mNGS group and underwent both culture and mNGS testing; the patients in the control group were only subjected to culture test. The effectiveness of mNGS was evaluated for microbial composition and diagnostic accuracy in every pleural effusion specimen type. RESULTS: We found that the positive rate of mNGS was 70% (28/40). The comparison between mNGS and culture method resulted that the sensitivity was 100% (95% CI: 29.2–100%) and the specificity was 64.9% (95% CI: 47.5–79.8%). The positive predictive value of mNGS was 18.8% (95% CI, 13.0–26.3%), and the negative predictive value was 100%. The most commonly identified potential pathogens were bacteria, such as Streptococcus, Prevotella, Parvimonas, Porphyromonas and Gemella. The most detected fungal infection was Candida and Pneumocystis. A total of 11 patients were identified as mixed infection by mNGS. Treatment regimen adjustments were made according to mNGS results and the overall length of hospital stay in the mNGS group was shorter compared to that of the control group. CONCLUSION: In this study, mNGS produced higher positive rates than the culture method in detecting pathogens in the pleural effusion specimens. The technology performed satisfactorily, providing more diagnostic evidence and reducing the length of hospital stay.