Mycobacterium abscessus Soft Tissue Infection: Review of Published Cases and Challenges in Treatment

Nationwide Increasing Incidence of Nontuberculous Mycobacterial Diseases Among Adults in Denmark: Eighteen Years of Follow-Up

BACKGROUND

The epidemiology of nontuberculous mycobacteria (NTM) infections is not well described. In this study, we sought to determine the incidence and prevalence of NTM infections and focus on social risk factors. In addition, we describe people with pulmonary and extrapulmonary NTM.

RESEARCH QUESTION

What are the incidence and prevalence of NTM in Denmark, and what are the characteristics of the affected patients?

STUDY DESIGN AND METHODS

This is a nationwide retrospective register-based cohort study in Denmark. Adult patients in the Danish national registers who received a diagnosis of NTM disease from 2000 to 2017 were classified as having either pulmonary or extrapulmonary NTM disease.

RESULTS

We identified 1,146 adults with an NTM diagnosis. Of these, 661 patients had pulmonary NTM, of whom 50.4% were male, whereas 485 had extrapulmonary NTM, of whom 59.6% were male. The median age (interquartile range) was 66 (18) years and 57 (32) years, respectively. The yearly incidence rate per 100,000 increased between 2000 and 2017 for both pulmonary NTM (0.4 to 1.3) and extrapulmonary NTM (0.3 to 0.6). The annual prevalence per 100,000 inhabitants increased from 0.4 to 3.5 for pulmonary NTM and from 0.3 to 1.0 for extrapulmonary NTM. The incidence rate increased with age. The incidence of pulmonary NTM was highest among those who were aged 70 years or older (19.3 per 100,000 inhabitants). Compared with patients with pulmonary NTM, patients with extrapulmonary NTM were more likely to be employed and had a higher educational level.

INTERPRETATION

This study indicates that the prevalence of NTM disease in Denmark increased between 2000 and 2017. We found that patients with pulmonary NTM and patients with extrapulmonary NTM represent two distinct groups that differ in age, sex, education, and employment status. Increased suspicion of pulmonary NTM disease is warranted in older adults after exclusion of more common lung infections.

Dermatology practice updates in mycobacterial disease

Atypical mycobacterial infections are commonly acquired through exposure to water, and tuberculosis remains highly endemic in many parts of the world. In this era of global connection, travel, and immigration, it is more important than ever to maintain a high index of suspicion for infection from cutaneous tuberculosis and atypical mycobacteria. Epidemics related to surgical procedures have been related to inadequate sterilization, as almost 50% of public water supplies harbor mycobacteria. Improved diagnostic techniques for these microbes, including Auramine-Rhodamine staining and rapid detection of mycobacteria and drug susceptibilities through PCR and MALDI-TOF, have improved detection and treatment outcomes. Given an increasing number of patients on immunosuppressive therapies, clinicians must remain vigilant.

Cutaneous Mycobacterium Abscessus Infection Following Plastic Surgery: Three Case Reports

Aim

Mycobacterium abscessus is ubiquitous in the environment and seldom causes infections in immunocompetent individuals. However, skin and soft tissue infections caused by M. abscessus have been reported in recent years. Additionally, the cutaneous infections or outbreaks post cosmetic surgery caused by M. abscessus have been increasing due to the popularity of plastic surgery. The main modes of transmission are through contaminated saline, disinfectants, or surgery equipment, as well as close contact between patients. This article describes three patients who were admitted to our hospital between November 2019 and October 2020. They presented with long-term non-healing wounds caused by M. abscessus infection after undergoing plastic surgery. Symptoms presented by the three patients included swelling, ulceration, secretion, and pain. After identification of M. abscessus with Ziehl-Neelsen staining and MALDI-TOF MS system, the patients were treated with surgical debridement and clarithromycin.

Conclusion

It is important to note that a long-term wound that does not heal, especially after plastic surgery, should raise suspicion for M. abscessus infection. The infection mechanism in these three patients may have been due to exposure to surgical equipment that was not properly sterilized or due to poor sterile technique by the plastic surgeon. To prevent such infections, it is important to ensure proper sterilization of surgical equipment and saline.