Clinical characteristics of extrapulmonary nontuberculous mycobacteria infections in comparison with pulmonary infections: A single-center, retrospective study in Japan

Keitaro Omori; Hiroki Kitagawa; Kakuhiro Yamaguchi; Shinjiro Sakamoto; Yasushi Horimasu; Takeshi Masuda; Shintaro Miyamoto; Taku Nakashima; Hiroshi Iwamoto; Kazunori Fujitaka; Hironobu Hamada; Kayoko Tadera; Toshihito Nomura; Norifumi Shigemoto; Gaku Aoki; Noboru Hattori; Hiroki Ohge

doi:10.1016/j.jiac.2023.05.013

Clinical characteristics of extrapulmonary nontuberculous mycobacteria infections in comparison with pulmonary infections: A single-center, retrospective study in Japan

J Infect Chemother. 2023 Sep;29(9):875-881. doi: 10.1016/j.jiac.2023.05.013. Epub 2023 May 19.

Authors

Keitaro Omori¹, Hiroki Kitagawa², Kakuhiro Yamaguchi³, Shinjiro Sakamoto³, Yasushi Horimasu³, Takeshi Masuda³, Shintaro Miyamoto³, Taku Nakashima³, Hiroshi Iwamoto³, Kazunori Fujitaka³, Hironobu Hamada³, Kayoko Tadera⁴, Toshihito Nomura⁵, Norifumi Shigemoto⁶, Gaku Aoki⁷, Noboru Hattori³, Hiroki Ohge⁵

Affiliations

¹ Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan; Department of Molecular and Internal Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan. Electronic address: a722@hiroshima-u.ac.jp.
² Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan; Department of Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
³ Department of Molecular and Internal Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
⁴ Section of Clinical Laboratory, Department of Clinical Support, Hiroshima University Hospital, Hiroshima, Japan; Division of Clinical Laboratory Medicine, Hiroshima University Hospital, Hiroshima, Japan.
⁵ Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan.
⁶ Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan; Department of Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan; Translational Research Center, Hiroshima University, Hiroshima, Japan.
⁷ Department of Biostatistics, Clinical Research Center, Hiroshima University Hospital, Hiroshima, Japan.

PMID: 37209842
DOI: 10.1016/j.jiac.2023.05.013

Abstract

Introduction: The prevalence of nontuberculous mycobacteria (NTM) infections is increasing worldwide. Although NTM can affect extrapulmonary organs, studies on the clinical characteristics of extrapulmonary NTM are rare.

Methods: We retrospectively analyzed patients who were newly diagnosed with NTM infections at Hiroshima University Hospital between 2001 and 2021 to investigate species distribution, infected sites, and risk factors of extrapulmonary NTM compared to pulmonary NTM.

Results: Of the 261 NTM infections, 9.6% and 90.4% had extrapulmonary and pulmonary NTM, respectively. The mean ages of patients with extrapulmonary and pulmonary NTM were 53.4 and 69.3 years, 64.0% and 42.8% were male, 36.0% and 9.3% received corticosteroids, 20.0% and 0% had acquired immune deficiency syndrome (AIDS), and 56.0% and 16.1% had any immunosuppressive conditions, respectively. Younger age, corticosteroid use, and AIDS were associated with extrapulmonary NTM. In pulmonary NTM, Mycobacterium avium complex (MAC) accounted for 86.4% of NTM species, followed by M. abscessus complex (4.2%), whereas in extrapulmonary NTM, M. abscessus complex, MAC, M. chelonae, and M. fortuitum accounted for 36.0%, 28.0%, 12.0%, and 8.0%, respectively. Compared to pulmonary NTM, extrapulmonary NTM were significantly more likely to be rapid-growing mycobacteria (RGM) (56.0% vs. 5.5%). The most common sites of infection were the skin and soft tissues (44.0%), followed by the blood (20.0%), tenosynovium, and lymph nodes (12.0%).

Conclusion: Younger age and immunosuppressive conditions are associated with extrapulmonary NTM, with a higher prevalence of RGM in extrapulmonary NTM than in pulmonary NTM. These results provide a better understanding of extrapulmonary NTM.

Keywords: AIDS; Corticosteroid; Extrapulmonary; Immunosuppression; Nontuberculous mycobacteria; Rapid-growing mycobacteria.

Copyright © 2023 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.

MeSH terms

Acquired Immunodeficiency Syndrome*
Aged
Female
Humans
Japan / epidemiology
Male
Middle Aged
Mycobacterium Infections, Nontuberculous* / diagnosis
Mycobacterium avium Complex
Nontuberculous Mycobacteria
Pneumonia*
Retrospective Studies