Clinical utility of metagenomic next-generation sequencing (mNGS) and a novel PCR-based point-of-care testing (POCT)...

Metagenomic next-generation sequencing (mNGS) and multiple point-of-care testing (POCT) techniques have demonstrated significant potential in pathogen detection. However, neither technology fully meets all clinical diagnostic needs for pulmonary infections. This study aimed to evaluate the complementary detection performance and clinical applicability of POCT and mNGS in pulmonary infections, using conventional culture as a reference.

This study enrolled forty-five patients with suspected lower respiratory tract infections for concurrent evaluation using POCT and mNGS. The detection performance of traditional culture methods, POCT, and mNGS was subsequently analyzed and compared.

Both molecular methods showed high positive detection rates, surpassing that of the culture method. When conventional culture was used as the gold standard, the sensitivity and positive predictive value (PPV) within the detection range of the PM Easy Lab Respiratory Panel (RP) were 97.1% and 80.5%, respectively, whereas for mNGS, these values were 90.2% and 92.5%, respectively. A comparison of the PM Easy Lab RP and mNGS results revealed that the PM Easy Lab was faster (100 min vs. 24 h) and more sensitive (88 vs. 63 pathogens) within its detection range, whereas mNGS offered a broader spectrum of pathogen detection. The overall consistency between PM Easy Lab RP and mNGS was 88.9%. Klebsiella pneumoniae and Acinetobacter baumannii were identified as the most prevalent bacterial infections by all three detection methods. Moreover, both PM Easy Lab RP and mNGS demonstrated enhanced capability over culture in detecting mixed infections (57.8%, 84.4% vs. 15.6%, all P < 0.01), uncovering a substantial number of viral and bacterial-viral co-infections that are undetectable by conventional culture methods. The most common combination of mixed infections in the PM Easy Lab RP was mixed bacterial infections (76.9%, 20/26), whereas in mNGS, it was bacterial-fungal-viral mixed infections (36.8%, 14/38).

The findings indicate that PM Easy Lab RP and mNGS offer distinct yet complementary value. PM Easy Lab has potential advantages in speed, sensitivity, and efficiency in detecting pathogens within its panel, and it could be considered for rapid, frontline testing, while mNGS provides a broad-spectrum detection capability, making it more suitable for comprehensive investigation of complex cases, though careful clinical interpretation is required to distinguish pathogenic from colonizing or contaminating organisms. Understanding their respective strengths can guide the development of optimized, hierarchical diagnostic pathways.