Laboratory-based surveillance of non-tuberculous mycobacterial pulmonary disease in Japan

Background: Intractable pulmonary diseases with non-tuberculous mycobacteria (NTM-PDs) and antimicrobial resistance have become increasingly concerning worldwide. Nevertheless, a surveillance system for NTM has not been established in most countries, thus requiring repeated, intermittent, and time-consuming cross-sectional nationwide surveys. Methods: To establish a nationwide surveillance system for NTM-associated diseases, we aimed to develop a prototype computer system primarily designed to continuously estimate NTM-PD incidence using a bacteriological case-defining algorithm through an automatic process of integrating bacteriological data collected from microbiology laboratories across Japan. To validate the accuracy of our study results, we compared the distribution of pulmonary TB cases between our laboratory data and the national surveillance data, which is representative of the Japanese population. Results: Our estimates implied a 17.7% increase in NTM-PD incidence from 15.8 [14.9-16.8] in 2013 to 19.2 [18.2-20.4] in 2017, per 100,000 population. Moreover, 93.0% of the identified NTM-PD cases were dominated by the Mycobacterium avium-intracellulare complex, and the proportion of M. abscessus species exceeded that of M. kansasii for the first time in Japan. We also revealed significant age and sex differences in NTM-PDs. Notably, we found similar characteristics between our laboratory data and national surveillance data covering almost the entire Japanese population. Conclusion: These findings, despite being laboratory-based, are extrapolatable to the general population in Japan and provide evidence that supports our system as a viable alternative to the nationwide NTM surveillance system. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This research was supported by the Research Program on Emerging and Reemerging Infectious Diseases of the Japan Agency for Medical Research and Development (AMED; 23fk0108673h0801) ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study was approved by the Ethics Committee of Fukujuji Hospital (approval #19046) I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data generated in this study are essentially unavailable.