Diagnostic performance and clinical impacts of metagenomic sequencing after allogeneic hematopoietic stem cell transplantation

Background: Metagenomic Next -Generation Sequencing (mNGS) is a rapid, culture-based, high-throughput technique for pathogen diagnosis. Despite its numerous tages, only a few studies have investigated its use in patients undergoing allogeneic poietic stem cell transplantation (allo-HSCT). Methods: We conducted a retrospective analysis of 404 mNGS tests performed on 264 after allo-HSCT. The tests were divided into three groups (Phase A, B, C) based on the spent hospitalized post -transplantation, and we evaluated the analytical performance mNGS in comparison with conventional microbiological tests (CMT), while also analyzing clinical utility for clinical impacts. Results: Metagenomic sequencing demonstrated a significantly higher rate of positive ological findings as compared to CMT (334/404 (82.7 %) vs. 159/404 (39.4 %), respectively, P < 0.001). The detection rates by both mNGS and CMT varied across the three-phase A-60/89 (67.4 %), B-147/158 (93.0 %), C-125/157 (79.6 %), respectively, P < 0.001; CMT: 89 (23.6 %), B-79/158 (50.0 %), C-59/157 (37.6 %), respectively, P < 0.001). The infection and types of pathogens were also different across the three phases. Compared to non-GVHD cases, mNGS detected more Aspergillus spp. and Mucorales in GVHD patients (Aspergillus: 12/102 (11.8 %) vs. 8/158 (5.1 %), respectively, P = 0.048; Mucorales: 6/102 (5.9 %) vs. 2/158 (1.3 %), respectively, P = 0.035). Forty-five (181/404) percent of mNGS tests yielded a positive impact on the clinical diagnosis, while 24.3 % (98/404) of tests benefited the patients in antimicrobial treatment. Conclusion: mNGS is an indispensable diagnostic tool in identifying pathogens and optimizing antibiotic therapy for hematological patients receiving allo-HSCT. Copyright <feminine ordinal indicator> 2023, Taiwan Society of Microbiology. Published by Elsevier Taiwan LLC. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/bync-nd/4.0/).