Clinical impact of 16S rRNA RC-PCR NGS on infectious disease management.

16S rRNA metagenomics provides a culture-independent method for diagnosing infections with fastidious or uncultivable organisms, guiding targeted therapy, and detecting polymicrobial communities. This study utilizes reverse complement (RC)-PCR next-generation sequencing (NGS) to accurately identify bacterial pathogens from clinical specimens and assess its impact on clinical decision-making, setting it apart from conventional 16S sequencing approaches. A retrospective analysis of an ISO 15189 accredited 16S RC-PCR NGS diagnostic workflow targeting the V1-6 and V9 regions of the 16S rRNA gene was conducted over a 2-year period, including 390 clinical specimens from 316 patients. 16S RC-PCR NGS results were discussed in a multidisciplinary consultation and subsequently reported to the clinic. In total, 1,283 RC-PCR results were analyzed, of which 517 were from clinical specimens, 284 were negative controls, 66 were positive controls, and 416 were from wet lab and bioinformatic pipeline validation. 16S RC-PCR NGS assay detected bacterial taxa in 179/390 (45.9%) of clinical specimens, while 201/390 (51.5%) were negative, and 10/390 (2.6%) yielded uninterpretable results. The specimen types pus, pleural fluid, and heart valves exhibited the highest positivity rate (68% to 70%). Overall, 16S RC-PCR NGS influenced diagnostic decision making in 145/282 (51.4%) clinical cases and guided therapeutic management in 77/282 (27.3%) cases. Results providing definite evidence for either the presence or absence of bacterial infection were considered clinically valuable. Integration of 16S RC-PCR NGS pathogen detection with multidisciplinary consultation markedly improved clinical management, directly impacting diagnosis and treatment of complex clinical cases in a tertiary care setting. The effect was most pronounced in brain abscess patients, where RC-PCR results guided treatment decisions in 9/13 (69.2%) of cases.IMPORTANCETimely and accurate diagnosis is essential for managing serious infections, yet clinicians often face situations where routine laboratory tests do not provide clear answers. This study demonstrates that next-generation sequencing (NGS) of the bacterial 16S rRNA gene can decisively resolve these uncertainties. By revealing whether bacteria are present in clinical specimens, this approach influenced clinical reasoning and supported treatment decisions across a variety of challenging cases. 16S reverse-complement PCR was especially powerful for brain abscesses and infections where the causative microorganism was unclear, providing clarity that directly improved patient care. These findings show that integrating advanced sequencing with expert clinical interpretation can enhance the management of complex infections and support more confident, evidence-based therapy.