Nasopharyngeal Mycobacterium abscessus Infection: A Case Report and Literature Review

Masanori Kaji; Ho Namkoong; Genta Nagao; Shuhei Azekawa; Kensuke Nakagawara; Hiromu Tanaka; Atsuho Morita; Takanori Asakura; Hirofumi Kamata; Yoshifumi Uwamino; Mitsunori Yoshida; Koichi Fukunaga; Naoki Hasegawa

doi:10.2147/IDR.S415197

Nasopharyngeal Mycobacterium abscessus Infection: A Case Report and Literature Review

Infect Drug Resist. 2023 Jun 20:16:3955-3963. doi: 10.2147/IDR.S415197. eCollection 2023.

Authors

Affiliations

¹ Division of Pulmonary Medicine, Department of Medicine, Keio University School of Medicine, Tokyo, Japan.
² Department of Infectious Diseases, Keio University School of Medicine, Tokyo, Japan.
³ Department of Clinical Medicine (Laboratory of Bioregulatory Medicine), Kitasato University School of Pharmacy, Tokyo, Japan.
⁴ Department of Respiratory Medicine, Kitasato University, Kitasato Institute Hospital, Tokyo, Japan.
⁵ Department of Laboratory Medicine, Keio University School of Medicine, Tokyo, Japan.
⁶ Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, Japan.

Abstract

Background: Mycobacterium abscessus (M. abscessus) is a rapidly growing bacterium (RGM) that causes refractory pulmonary and extrapulmonary infections. However, studies investigating pharyngeal and laryngeal M. abscessus infections are limited.

Case presentation: A 41-year-old immunocompetent woman complaining of bloody sputum was referred to our hospital. Although her sputum culture tested positive for M. abscessus subsp. abscessus, radiological findings were not indicative of pulmonary infection or sinusitis. Further diagnostic workup, including laryngeal endoscopy and positron emission tomography/computed tomography (PET/CT), confirmed the presence of nasopharyngeal M. abscessus infection. The patient was initially treated with intravenous amikacin, imipenem/cilastatin, azithromycin, and clofazimine for 28 days, after which the patient was provided with amikacin, azithromycin, clofazimine, and sitafloxacin for four months. After the completion of antibiotic therapy, the patient showed negative results on sputum smear and culture and normal findings on PET/CT and laryngeal endoscopy. Whole-genome sequencing of this strain revealed that it belonged to the ABS-GL4 cluster, which has a functional erythromycin ribosomal methylase gene, although it is not a major lineage in non-cystic fibrosis (CF) patients in Japan and Taiwan and in CF patients in European countries. We conducted a literature review and identified seven patients who developed pharyngeal/laryngeal non-tuberculous mycobacterium (NTM) infection. Four of the eight patients had a history of immunosuppressant use, including steroids. Seven of the eight patients responded well to their treatment regimens.

Conclusion: Patients whose sputum culture tests are positive for NTM and who meet the diagnostic criteria for NTM infection but do not have intrapulmonary lesions should be evaluated for otorhinolaryngological infections. Our case series revealed that immunosuppressant use is a risk factor for pharyngeal/laryngeal NTM infection and that patients with pharyngeal/laryngeal NTM infections respond relatively well to antibiotic therapy.

Keywords: laryngeal NTM; pharyngeal NTM; whole-genome sequencing.

Publication types

Case Reports

Grants and funding

This study was funded by AMED (Japan Agency for Medical Research and Development) (JP22wm0325044, JP21fk0108621, and JP22wm0325055), a JSPS Grant-in-Aid for Young Scientists (21K15667), Grant-in-Aid for Scientific Research (21KK0148 and 22H03122), a JAID Clinical Research Promotion Grant, The Mitsubishi Foundation (Research Grants in the Natural Sciences), and JST PRESTO (JPMJPR21R7).