Cross-transmission Is Not the Source of New Mycobacterium abscessus Infections in a Multicenter Cohort of Cystic Fibrosis Patients. (19th June 2019)

• Record Type: Journal Article
• Authors: Doyle, Ronan M; Rubio, Marc; Dixon, Garth; Hartley, John; Klein, Nigel; Coll, Pere; Harris, Kathryn A
• Is Part Of: Clinical infectious diseases. Volume 70:Number 9(2020)
• Page Start: 1855
• Page End: 1864
• Publication Date: 2019-06-19
• Subjects: nontuberculous mycobacteria -- whole-genome sequencing -- transmission -- cystic fibrosis -- phylogenomics; Communicable diseases -- Periodicals; 616.905
• DOI: 10.1093/cid/ciz526
• Languages: English
• ISSNs: 1058-4838

Abstract

Abstract: Background: Mycobacterium abscessus is an extensively drug–resistant pathogen that causes pulmonary disease, particularly in cystic fibrosis (CF) patients. Identifying direct patient-to-patient transmission of M. abscessus is critically important in directing an infection control policy for the management of risk in CF patients. A variety of clinical labs have used molecular epidemiology to investigate transmission. However, there is still conflicting evidence as to how M. abscessus is acquired and whether cross-transmission occurs. Recently, labs have applied whole-genome sequencing (WGS) to investigate this further and, in this study, we investigated whether WGS can reliably identify cross-transmission in M. abscessus . Methods: We retrospectively sequenced the whole genomes of 145 M. abscessus isolates from 62 patients, seen at 4 hospitals in 2 countries over 16 years. Results: We have shown that a comparison of a fixed number of core single nucleotide variants alone cannot be used to infer cross-transmission in M. abscessus but does provide enough information to replace multiple existing molecular assays. We detected 1 episode of possible direct patient-to-patient transmission in a sibling pair. We found that patients acquired unique M. abscessus strains even after spending considerable time on the same wards with other M. abscessus– positive patients. Conclusions: This novel analysis has demonstrated that the majority of patients in this study have not acquired M. abscessus through direct patient-to-patient transmission or a common reservoir. Tracking transmission using WGS will only realize its full potential with proper environmental screening, as well as patient sampling. Abstract : Whole-genome sequencing should replace the current molecular typing used routinely in clinical microbiology laboratories. The patient-to-patient spread of Mycobacterium abscessus is not common. Environmental screening may provide a better understanding of the acquisition of M. abscessus infections.