238. Direct identification of Bacterial Species with MinION Nanopore Sequencer In Clinical Specimens Suspected of Polybacterial Infection

BACKGROUND: Conventional culture tests usually identify only a few bacterial species, which can grow well in the culture system, in the cases of polybacterial infection. 16S rRNA gene nanopore sequencing enables semi-quantitative identification of bacterial genetic materials. We aimed to evaluate usefulness of 16s rRNA gene nanopore sequencing in the cases suspected of polybacterial infection. METHODS: The research was conducted in a single university hospital for one year. Conventional bacterial culture identification and nanopore sequencing of 16s rRNA gene were carried out simultaneously for cases where polybacterial infection is strongly suspected. Blood agar plate was used for conventional culture, and Microscan (Beckman Coulter, United States) and Vitek 2 (Biomerieux, FR) automated systems were used for identification. For nanopore sequencing, 16S rRNA gene PCR was performed from the clinical specimens, and sequencing libraries were generated from the PCR products using the rapid barcoding sequencing kit (Oxford nanopore technologies, UK). MinION sequencing was performed for 1–3 hours and the generated reads were analyzed using the EPI2ME 16S BLAST workflow. RESULTS: Specimens were obtained from 15 patients; 6 liver abscess, 2 psoas abscess, 2 thigh abcess, 1 paraspinal abscess, 1 mycotic aneurysm, 1 necrotizing fasciitis, 1 fingertip gangrene and 1 abscess in coccyx area. 16s rRNA gene nanopore sequencing showed monobacterial organism in 8 (53.3%) specimens and polybacterial organisms in 7 (46.6%) specimens. In three (37.5%) cases of 8 cases with monobacterial infections identified by 16s rRNA gene sequencing, no organism was grown in conventional culture, possibly due to previous antibiotic administration. Notably, among 8 cases with polybacterial infection by 16s rRNA gene nanopore sequencing test, traditional culture test showed polybacterial infection in only two (25%) cases and single bacterial organism was identified in the other 6 (75%) cases. CONCLUSION: Nanopore sequencing of 16s rRNA gene using the MinION sequencer may be useful for identification of causing microorganism and differentiation between monobacterial and polybacterial infection when polybacterial infection is suspected. DISCLOSURES: All authors: No reported disclosures.