Epidemiology, risk factors, and outcomes of adult cutaneous non‐tuberculous mycobacterial infection over a 10‐year period in Singapore

Abstract

Background Unfamiliarity with the presentation, diagnostic process, and treatment of cutaneous non‐tuberculous mycobacterium (NTM) infection leads to poorer outcomes. We describe our experience with managing cutaneous NTM infection in a regional hospital in Singapore from 2005 to 2014. Methods Adult patients with cutaneous NTM infections were identified through positive skin tissue cultures in this retrospective case series. We excluded patients younger than 21 years of age, patients whose care was transferred to another hospital, and patients with catheter‐related infections. Data including demographic variables, as well as disease and treatment outcomes, were collected. We compared the data between patients with and without risk factors for immunosuppression to look for any significant difference. Results Fifty‐eight cases were reviewed. Mycobacterium abscessus was the commonest organism isolated (51.7%), and abscesses or inflamed cysts were the most common presentation. Nineteen specimens (57.6%) showed suppurative or necrotizing granulomatous dermatitis on biopsy and acid‐fast bacilli were identified in 2 of 21 histologic specimens (9.5%) stained for mycobacterium. Treatment included systemic antibiotics, surgery, or both. In total, 33 cases had clinical resolution while 25 cases were lost to follow‐up. Our study was limited by the under‐reporting of cases, bias due to data from a single center, and high dropout rates, thereby precluding a detailed assessment of treatment outcomes. Conclusions A high index of suspicion is required to diagnose cutaneous NTM infection. Education of both patients and physicians will help to raise the level of awareness and reduce treatment delays.

A Case of Pediatric Subcutaneous Abscess Caused by <i>Mycobacterium mageritense</i> Infection

“…of M. mageritense bacteremia followed by skin abscess, although skin and soft tissue infection is a common presentation of non-tuberculous mycobacterium infection (11).…”

DNA microarray chip assay in new use: early diagnostic value in cutaneous mycobacterial infection

“…The present study identified 5 MTB and 55 NTM positive cutaneous infections by combining clinical spectrum and etiological examination. In general, the incidence of NTM infections has been on the rise ( Wentworth et al., 2013 ; Mei et al., 2019 ; Yeo et al., 2019 ) and the same was evidenced by the increased number of cutaneous mycobacterial infection cases detected from 2019 to 2021 in our hospital. In addition to the general increase of infections, improved diagnostic accuracy was responsible for the augmented incidence of cutaneous mycobacterial infections ( Wang and Pancholi, 2014 ).…”

Treatment of non-tuberculosis mycobacteria skin infections

“…Combined antibiotics treatment is often required, and surgical therapy may be needed optionally ( Philips et al, 2019 ). After reviewing several in vitro antimicrobial susceptibility research ( Forbes et al, 2018 ; Yeo et al, 2019 ; Da et al, 2020 ; Kumar et al, 2021 ; Das et al, 2022 ), we found that M. fortuitum strains were susceptible to many antibiotics. The isolates are susceptible to amikacin (intermediate to highly sensitive), ciprofloxacin (highly susceptible), doxycycline (intermediate susceptible), clofazimine, trimethoprim-sulfamethoxazole (TMP-SMX) and linezolid, resistance to all the antituberculosis agents, while different to macrolides (decreased sensitivity due to inducible susceptibility) and imipenem.…”