Nontuberculous Mycobacteria

Successful management of surgical site infection caused by Mycobacterium mageritense in a breast cancer patient

Mycobacterium mageritense (M. mageritense), a nontuberculous mycobacterium, is classified as a rapidly growing mycobacterium, class IV in the Runyon Classification. This bacterium is found in soil, water, and other habitats. Infections caused by M. mageritense are relatively rare and no treatment protocol has been established. Herein, we report a case of skin and soft tissue infection caused by M. mageritense. A 49-year-old woman underwent surgery for right breast cancer. Four months after surgery, a surgical site infection was found, and M. mageritense was identified in the wound culture using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Based on the sensitivity results, the patient was treated with levofloxacin and doxycycline for 4 months. In addition to antimicrobial agents, aggressive surgical interventions led to a favorable course of treatment. In conclusion, successful treatment of skin and soft tissue infections with M. mageritense requires surgical intervention whenever possible, aggressive susceptibility testing, and appropriate antimicrobial therapy.

Formulation and Stability of a 1% Clarithromycin-Based Topical Skin Cream: A New Option to Treat Buruli Ulcers?

There are more than 170 known species of non-tuberculous mycobacteria, and some are responsible for serious diseases in people infected with them. One of these is Buruli ulcers, a neglected tropical disease endemic in more than 33 countries and caused by Mycobacterium ulcerans, which infects skin tissue. Treatment consists of a long-term regimen combining the use of oral rifampin with another anti-tuberculosis drug (e.g., clarithromycin). Patients in these countries face difficulties in accessing and adhering to this therapy. This study investigates the feasibility of formulating stable, optimized clarithromycin as a topical cutaneous cream. The cream was formulated, and its stability was evaluated under different storage temperature conditions and using a stability indicator method. The results showed that the clarithromycin cream was stable for at least 60 days, even at extreme temperatures (40 °C). In conclusion, the data presented here demonstrate the stability of a new form of topical cutaneous clarithromycin, which may offer a new approach to the treatment of Buruli ulcers and clarithromycin-sensitive infections.

Nasal Septal Perforation and Widespread Skin Lesions Caused by Mycobacterium chelonae Infection Mimicking Granulomatosis with Polyangiitis

Mycobacterium chelonae, a rapidly growing mycobacterium found in the natural environment, is known to cause localized lesions in the skin, soft tissue, and bone through traumatic inoculation, but widespread lesions are uncommon. We herein report an immunocompromised 79-year-old man suspected of having polyangiitis granulomatosis due to weight loss, epistaxis, and nasal crusts with impending septal perforation who was subsequently diagnosed with mucocutaneous and bone disease caused by widespread M. chelonae infection. Given these findings, clinicians should be aware of the tendency to develop unusual widespread lesions in immunocompromised patients, which can present a clinical picture similar to systemic vasculitides, such as granulomatosis with polyangiitis.

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.

Infectious Granuloma With Mycobacterium abscessus After Facial Injection of Botulinum Toxin: A Case Report

Botulinum toxin injections have garnered increasing employment in facial rhytidectomy due to their demonstrable efficacy and safety profile. In this study, the authors present the case of a 39-year-old woman who manifested painful crimson nodules and multiple abscesses on her face, which manifested 1 week postinjection. Subsequent histopathological scrutiny unveiled the development of histiocytic granulomas accompanied by infiltrates of inflammatory cells, and microbiological investigation and polymerase chain reaction assays identified the causative agent as Mycobacterium abscessus .

Mycobacterium senegalense Infection in Kidney Transplant Patient with Diabetes, Memphis, Tennessee, USA

Fewer than 30 cases of Mycobacterium senegalense infection have been reported. We report a complicated case of M. senegalense infection in Memphis, Tennessee, in the southeastern United States. The patient's comorbidities of past organ transplant and insulin-dependent diabetes required delicate consideration of those health conditions to guide treatment.

Epidemiology, clinical characteristics, and outcomes of nontuberculous mycobacterial skin, soft tissue, and bone infections from a single center over a 10-year period

Introduction

Non-tuberculous mycobacteria (NTM) cause a wide variety of clinical syndromes. Data guiding diagnosis and treatment of NTM skin and soft tissue infections (SSTI) and bone infections are limited. We sought to better understand SSTI and bone infections caused by NTM.

Methods

All NTM clinical isolates recovered at Brooke Army Medical Center from 2012 to 2022 were screened; SSTI and bone isolates were included. Electronic health records were reviewed for epidemiologic, microbiologic, and clinical data. Infections were defined as recovery of one or more NTM isolate from skin, soft tissue, or bone cultures with a corresponding clinical syndrome.

Results

Forty isolates of skin, soft tissue, or bone origin from 29 patients were analyzed. Twenty (69 %) patients, majority female (14/20, 70 %), had infecting isolates, most commonly secondary to surgery (35 %) or trauma (35 %). Six of 20 (30 %) had bone infections. Time from symptom onset to isolate recovery was a median 61 days (IQR 43-95). Eight (40 %) had combined medical/surgical therapy, 8 (40 %) had surgery alone, and 4 (20 %) had medical therapy alone. M. abscessus was more frequently isolated from patients with true infections.

Conclusions

Data supporting diagnosis and treatment decisions in NTM SSTI/bone infections is sparse. In this study the majority of NTM isolated were true infections. We confirm that surgery and trauma are the most common routes of exposure. The delay between symptom onset and directed therapy and the wide variety of treatment regimens highlight a need for additional studies delineating criteria for diagnosis and treatment.

Complications of Medical Tourism in Aesthetic Surgery: A Systematic Review

INTRODUCTION

As medical cost continues to rise, so has the use of medical tourism by patients as a more cost-effective alternative. While the upfront cost savings attract many unsuspecting patients from their country of origin, there are significant patient safety issues surrounding short- and long-term follow-up, as well as the management and cost of complications.

METHODS

A systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses on complications that presented after cosmetic surgeries performed abroad. The literature search was performed on October 18, 2022, using the databases of PubMed, Google Scholar, and Embase.

RESULTS

From the 44 studies that were included, 589 patients were identified who presented with complications after having a cosmetic procedure abroad. Infection was the most prevalent complication in this study followed by wound dehiscence, seroma/hematoma, and tissue necrosis. Ninety-eight percent of the infectious organisms were bacterial, and 81% of them were from the Mycobacterium genus.

CONCLUSIONS

Cosmetic tourism is a global phenomenon. This systematic review highlights the nature of complications following cosmetic tourism, the surgeries that resulted in complications, the countries that the primary procedures took place in, and the countries of origin of the patients. To aid in reducing morbidity and mortality from cosmetic tourism, regulatory bodies should educate and empower the public to aid them in making educated medical conditions when seeking care.

Non-tuberculous mycobacterial skin and soft tissue infections in the Northern Territory, Australia, 1989-2021

BACKGROUND

A previous review demonstrated that the majority of NTM infections in the Northern Territory (NT) are pulmonary in nature [1], however skin and soft tissue (SST) are likely the next most common sites of disease. The current epidemiology of NTM SST infections across the NT is not known. We aimed to establish the current and historical incidence rates, and the organisms involved.

METHODS

All NTM cases reported to the Centre for Disease Control in Darwin from 1989-2021 were retrospectively reviewed.

RESULTS

226 NTM notifications were reviewed. 73 (32%) cases were SST infections. The incidence of SST cases increased over the study period. Female cases were more common (p=0·002). Disease occurred across a wide age range (1-85 years). Only 16% of cases occurred in Aboriginal individuals which may reflect immunological factors requiring further investigation. Many cases had no clear provocation, but localised skin trauma was the most common risk factor. The most common organism identified was M. fortuitum (41%). Diagnosis was often delayed, with a median time to diagnosis of 69 days (IQR=31-149). Most cases (60%) underwent surgical intervention with adjunctive anti-mycobacterial medical therapy.

CONCLUSION

NTM SST incidence rates increased over the study period. NTM SST infections are a rare but important differential diagnosis for non-healing cutaneous wounds.

Photodynamic therapy: a new approach to the treatment of Nontuberculous Mycobacterial skin and soft tissue infections

Nontuberculous mycobacterial skin and soft tissue infections are rising and are causing social concern due to the growth of cosmetic dermatology and immune-compromised populations. For the treatment of nontuberculous mycobacteria, several novel strategies have been investigated. One of them, photodynamic therapy, is a recently developed therapeutic strategy that has shown promise in managing nontuberculous mycobacterial skin and soft tissue infections. In this review, we first present an overview of the current status of the therapy and then summarize and analyze the cases of photodynamic therapy used to treat nontuberculous mycobacterial skin and soft tissue infections. We also discussed the feasibility of photodynamic therapy for treating nontuberculous mycobacterial skin soft tissue infections and the related mechanisms, providing a potential new option for clinical treatment.

Disseminated cutaneous Mycobacterium chelonae infection secondary to an indwelling catheter in an immunocompetent host

Background

Mycobacterium chelonae is a species of nontuberculous mycobacteria that typically causes localized cutaneous disease in immunocompetent hosts. There have been few reports of disseminated infections in immunocompetent individuals which have often been associated with invasive medical procedures.

Case Presentation

In this report, we describe a 43-year-old immunocompetent female with an implanted venous access device who presented with skin lesions increasing in size and frequency over the course of five months despite antimicrobial therapy. A diagnosis was not made until mycobacterial culture from a skin biopsy grew M. chelonae.

Conclusion

Disseminated cutaneous M. chelonae infection can be a rare complication of indwelling venous catheterization among immunocompetent patients.

Colloidal silver against macrophage infections and biofilms of atypical mycobacteria

Skin and soft tissue infection (SSTI) caused by atypical mycobacteria such as Mycobacterium abscessus and Mycobacterium avium intracellulare complex (MAIC) have increased in recent years. Current therapeutic options are limited, and hence new and better therapies are urgently required. Colloidal Silver (CS) has been identified for its widespread antibacterial properties and silver-impregnated dressings have been used for SSTIs caused by various pathogens. The efficacy of Green Synthesized Colloidal Silver (GSCS) was investigated for bacterial growth inhibition (BGI) using a microdilution method and minimum biofilm eradication concentration (MBEC) using resazurin assay and confocal scanning laser microscopy (CSLM) of M. abscessus (n = 5) and MAIC (n = 5). The antibacterial effect of GSCS against M. abscessus infected macrophages was also evaluated. The in vitro cytotoxicity of GSCS on a human keratinocyte cell line (HaCaT) and neonatal foreskin fibroblasts was analyzed by the crystal violet proliferation assay. Average BGI and MBEC of GSCS varied between 0.7 and 22 ppm for M. abscessus and MAIC. The concentration of 3 ppm reduced M. abscessus-infection in macrophages significantly. GSCS was not cytotoxic to HaCaT and neonatal foreskin fibroblast cells at concentrations < 3 ppm up to 2 h exposure time. GSCS therefore, has the potential for topical application against atypical mycobacterial SSTI.

Lower Extremity Nodules After Spelunking in Mexico

Mycobacterium marinum is a non-tuberculous mycobacterium that presents as a nodular granulomatous disease. The bacillus can infect humans when broken skin is exposed to a contaminated aquatic environment. M. marinum infections are usually isolated to the skin and soft tissues and can spread in a lymphatic distribution. A 26-year-old male cut his right ankle while spelunking in Tulum, Mexico. He presented to his primary care physician three months after he sustained the laceration with a nonhealing wound on the right lateral posterior ankle. Examination of the lesion demonstrated erythematous, violaceous, and hyperpigmented indurated plaques with satellite lesions noted at the right medial, posterior, and lateral ankle. The lesion characteristics raised initial suspicion for an invasive fungal infection. Biopsy of the lesion demonstrated epidermal ulceration covered by neutrophilic serum, marked underlying dermal acute inflammation, and granulation tissue. A mild perivascular, predominantly lymphocytic infiltrate was present in the deep dermis with no evidence of granuloma. Acid-fast bacilli culture plated onto chocolate agar confirmed the species M. marinum.

Mycobacteria in Organ Transplant Recipients

This review describes the epidemiology and risk factors of tuberculosis (TB) in solid organ transplant recipients. We discuss the pre-transplant screening for risk of TB and management of latent TB in this population. We also discuss the challenges of management of TB and other difficult to treat mycobacteria such as Mycobacterium abscessus and Mycobacterium avium complex. The drugs for the management of these infections include rifamycins which have significant drug interactions with immunosuppressants and must be monitored closely.

Infections in patients with adverse reactions to the use of unknown modeling substances for soft tissue enhancement in Cali, Colombia

The infiltration of foreign materials not approved for medical purposes or of modeling substances used in soft tissue to modify the anatomical appearance for aesthetic purposes represents a serious health problem. These procedures lead to the development of delayed complications, including infections. The objective of this study was to characterize infections in patients with adverse reactions to the use of modeling substances in Cali, Colombia. A cross-sectional and descriptive study was used to determine the frequency of bacterial and fungal infections associated with complications from and adverse reactions to the use of modeling substances in 113 patients. We identified microorganisms in 22 patients and a frequency of 68.1% monomicrobial infections and 31.8% polymicrobial infections. The microorganisms identified in our study included Bacillus cereus, Mycobacterium fortuitum, and Pseudomonas stutzeri, among other microorganisms. The presence of adverse effects derived from the use of illegal modeling substances has been demonstrated; among these effects, infections occur with high frequency and place the health of the patient at risk and increase problems in health care.

Skin and soft tissue infection of Nontuberculous mycobacterium after injection lipolysis

BACKGROUND

Injection lipolysis is used for body and face contouring due to its minimal invasiveness and cost-effectiveness, but related complications such as nontuberculous mycobacterium infection significantly affect its clinical application.

AIMS

This study aimed to review the literature on NTM infection after injection lipolysis.

METHODS

We conducted a literature review of scientific journals published in Medline and PubMed up to September 2022 on patients with NTM skin and soft tissue infections. We used the keywords: nontuberculous mycobacterium, infection, injection lipolysis, and lipolytic solution in various combinations with the Boolean operators AND, OR, and NOT. Only articles available in English and full version publications were considered for this review. Here, we reviewed the relevant mechanisms and drugs for injectable lipolysis and analyzed the possible correlation between NTM infection and injection lipolysis. We also summarize methods for the diagnosis and treatment of NTM infections and present some perspectives on this therapy.

RESULTS

Many patients with NTM infections had a history of fat-related surgery or therapy. NTM infection after injection lipolysis may be related to inadequate disinfection and sterilization of injection equipment and clinical procedures, the unqualified medication itself and free fatty acids released during injection lipolysis. Currently, diagnosis and treatment of NTM infection after lipolysis injections remains challenging.

CONCLUSIONS

Injection lipolysis represents a helpful option for local fat reduction. Doctors should strictly abide by the aseptic operation standards and use qualified products for there is a correlation between skin and soft tissue infection of nontuberculous mycobacterium and injection lipolysis. Providers should understand the mechanism, indications, and associated risks of injection lipolysis when injecting fat-dissolving drugs to reduce localized fat.

Epidemiology, Outcomes and Tolerability of Protracted Treatment of Nontuberculous Mycobacterial Infections at a Community Teaching Hospital in the Southeastern United States

Nontuberculous mycobacterial (NTM) infections present a treatment challenge for clinicians and patients. There are limited data about current susceptibility patterns and treatment outcomes in U.S. adults. This was a 10-year, single-center, retrospective, observational cohort study of adults with a positive NTM culture and clinical suspicion of infection between 1 January 2010 and 30 June 2020. The primary objective was to identify predictors for favorable treatment outcomes. Key secondary objectives were characterization of NTM epidemiology, susceptibility profiles, and safety and tolerability of treatment, including the proportion of subjects with an antimicrobial change and the reasons for the change. Of 250 subjects diagnosed with NTM infection, the most prevalent NTM isolates were Mycobacterium avium intracellulare complex (66.8%) followed by Mycobacterium abscessus (17.6%). Antimicrobial susceptibility data were available for 52.4% of the cohort (45.8% slow growers; 54.2% rapid growers). Only 88 (35%) subjects received treatment with evaluable clinical outcomes. The proportion of subjects with a favorable outcome was 61.4%. More subjects in the unfavorable outcome group experienced a change in antimicrobial therapy (73.5% vs. 51.9%, p = 0.043). The most common reason for antimicrobial change was adverse drug events (n = 36, 67.9%). In the regression model, private insurance was associated with a favorable outcome, whereas having multiple antimicrobial changes was associated with an unfavorable outcome. The complexity of NTM treatment and high incidence of medication-related issues suggest the necessity of interdisciplinary collaboration to improve overall treatment outcomes in NTM infections.

Omadacycline for management of Mycobacterium abscessus infections: a review of its effectiveness, place in therapy, and considerations for use

The Mycobacterium abscessus complex (MABC) is a group of acid-fast, rapidly dividing non-tuberculous mycobacteria (NTM) that include a number of clinically important subspecies, including M. abscessus, M. bolletii, and M. massiliense. These organisms are prevalent in the environment and are primarily associated with human pulmonary or skin and skin structure infections (SSSI) but may cause more deep-seeded disseminated infections and bacteremia in the immunocompromised. Importantly, these NTM are resistant to most first-line anti-tuberculous agents and, due to intrinsic or acquired resistance, exhibit exceedingly low, variable, and geographically distinct susceptibilities to commonly used antibacterial agents including older tetracyclines, macrolides, aminoglycosides, cephalosporins, carbapenems, and sulfamethoxazole-trimethoprim. Omadacycline is a novel third-generation member of the tetracycline family of antibacterials that has recently been demonstrated to have potent anti-NTM effects and clinical efficacy against MABC, including M. abscessus. The purpose of this review is to present a comprehensive and up-to-date assessment on the body of literature on the role of omadacycline for M. abscessus infections. Specifically, the in vitro and in vivo microbiology, mechanisms of action, mechanisms of resistance, clinical pharmacokinetics, clinical efficacy, adverse effects, dosage and administration, and place in therapy of omadacycline in management of M. abscessus infections will be detailed.

Mycobacterium kansasaii and Mycobacterium scrofulaceum dual pulmonary infection in an immunocompetent male: first report from India

A 57-year-old farmer presented with chronic cough and recurrent hemoptysis, previously treated for sputum positive pulmonary tuberculosis. Referred to us for evaluation of drug resistant tuberculosis as his sputum was persistently positive for acid fast bacilli along with radiological worsening even after 6 months of antitubercular treatment. Bronchoalveolar lavage was done and he was diagnosed with a rare mixed non-tuberculous mycobacyteria (NTM) pulmonary infection despite no immune dysfunction. He was successfully treated with multidrug regimen of rifampicin, isoniazid, ethambutol and clarithromycin.

Mycobacterium chelonae Infection After a Cat Bite: A Rare Case Report

We describe a 62-year-old woman with a 1-month-old unhealed cat bite wound caused by Mycobacterium chelonae presenting with persistent infection despite treatment with cefazolin and amoxicillin. This is the first reported case of M. chelonae infection caused by a cat bite. Cat bites are affected by the cat’s food microbiome, so clinicians should consider the cat’s diet if wounds are not responding as expected to first-line therapy.

Photodynamic therapy, a promising treatment approach for cutaneous infectious granulomas

Cutaneous infectious granulomas are mainly caused by fungi and bacteria. Antibiotics are the primary therapeutic choices for the diseases, but the drug-resistant pathogens become increasingly prevalent. Thus, there is an urgent need to explore novel approaches to treating cutaneous infectious granulomas. Photodynamic therapy (PDT) is widely used as an alternative treatment for various kinds of skin diseases, and evidence has been accumulating that PDT is also effective for the treatment of cutaneous infectious granulomas. In this narrative review, we sought to summarize the recent literature concerning the applications and mechanisms of PDT in the treatment of cutaneous infectious granulomas. Clinical and basic research has demonstrated that PDT is an effective approach in treating fungal infections such as sporotrichosis and chromoblastomycosis. In addition, PDT is also used to treat atypical mycobacterial infections such as Mycobacterium marinum. PDT can significantly shorten the duration of antibiotics treatment, resulting in diminishment of adverse effects. The potential mechanisms of PDT are to kill the pathogens directly or elicit modulatory effects on the immune microenvironments. We conclude that PDT is a promising therapeutic choice for the treatment of cutaneous infectious granulomas.

A Rare Insidious Case of Skin and Soft Tissue Infection Due to Mycobacterium abscessus: A Case Report

Mycobacterium abscessus complex (MABc) is part of the rapid-growing non-tuberculous mycobacteria group that usually resides in natural water sources. When it affects humans, it can be highly resistant and difficult to manage. The most common presentation is localized, mainly in the lungs and soft tissue, but can be generalized in immunocompromised patients. Here we present a case report of a 40-year-old female with a chronic infection of the abdominal wall after abdominoplasty.

Nontuberculous mycobacterial skin and soft tissue infection in Hawai'i

Background

Hawaiʻi has the highest nontuberculous mycobacterial (NTM) lung infection prevalence in the United States. Limited data regarding skin and soft tissue infections (SSTI) due to NTM in Hawaiʻi exists. This study describes patient demographics, clinical courses of infection, treatment patterns, and clinical outcomes of NTM SSTIs in Hawaiʻi.

Methods

A retrospective chart review (n = 50) of patients diagnosed and treated at Hawaiʻi Pacific Health facilities for NTM SSTIs between January 2010 and July 2021 was conducted. Patient demographics, clinical course, and treatment data were collected from electronic medical records.

Results

Half of the patient population consisted of females, and the average age of patients during infection was 49 years (SD = 25.6). The majority of cases (80%) were caused by rapidly growing mycobacteria (RGM), most commonly Mycobacterium abscessus. NTM SSTI by race were Asian (48%), White (28%), and Native Hawaiian and Other Pacific Islanders (16%). Almost all Asian patients with NTM SSTI were Filipino or Japanese. Diagnosis was frequently delayed. The average time to diagnosis was 116 days. Most patients achieved complete resolution (72%) following a prolonged course of antimicrobial treatment (mean = 196 days) with surgical debridement.

Conclusion

Increased awareness among physicians and the community of non-mycobacterial skin infections is essential in Hawaiʻi due to the high prevalence of NTM and the high percentage of predisposed populations. Increased awareness of NTM could reduce delayed diagnosis and improve patient care. Further studies are required to inform optimal treatment and diagnostic strategies, improve patient outcomes, and aid public health surveillance efforts.

Mycobacterium abscessus and Mycobacterium massiliense exhibit distinct host and organ specificity: a cross-sectional study

PURPOSE

Precise subspeciation of Mycobacterium abscessus complex (MAB) is crucial for predicting antibiotic susceptibilities and patient outcomes. However, routine clinical microbiology laboratories have limited diagnostic tools for the differentiation of the subspecies. Thus, we investigated the predictors for MAB subspecies to actuate rapid differentiation and the optimal treatment plans.

METHODS

We retrospectively identified stored clinical isolates of MAB and reviewed patient medical records to compare clinical characteristics, sites of infection, and outcomes among patients infected with M. abscessus subsp. abscessus (M. abscessus) and M. abscessus subsp. massiliense (M. massiliense). MAB subspecies were characterized by multilocus sequence analysis with three-locus sequence (hsp65, rpoB, and secA1) and pulsed-field gel electrophoresis.

RESULTS

After outbreak and duplicated cases were excluded, 56 and 36 patients with infection caused by M. abscessus and M. massiliense, respectively, were included in the analysis. Patients with either cardiovascular disease or risk factors for cardiovascular disease (male gender and age ≥55 years) were 4.5 times more likely to harbor M. abscessus (P = 0.002), while M. massiliense was 4.8 times more frequently recovered from cutaneous and surgical wounds (P = 0.04).

CONCLUSION

Distinct host and organ specificity were observed among patients infected with M. abscessus and those with M. massiliense. These differences may provide clinically significant clues to optimize treatment strategies.

A new approach to the treatment of nontuberculous mycobacterium skin infections caused by iatrogenic manipulation: Photodynamic therapy combined with antibiotics: A pilot study

BACKGROUND

Recently, the number of nontuberculous mycobacterium (NTM) infections caused by iatrogenic procedures, especially rapid NTM skin infections, has been increasing. Due to the nonspecific clinical manifestations and nonstandard treatment guidelines, these infections are often misdiagnosed and challenging to treat.

METHODS

In this study, eight patients had NTM skin infections caused by iatrogenic procedures, and were diagnosed by bacterial culture and flight mass spectrometry tests. They were treated with 5-aminolevulinic acid-photodynamic therapy (ALA-PDT) combined with antibiotic therapy.

RESULTS

All eight patients enrolled in the study were cured with 100% efficacy after receiving combination therapy with ALA-PDT and antibiotics for 3-6 months. All patients experienced redness and pain during treatment but no other discomfort and were satisfified with the results of their treatments.

CONCLUSION

Local ALA-PDT combined with antibiotics is a safe and effective method of treating NTM skin infections.

Bloodstream infections with rapidly growing nontuberculous mycobacteria

Background

Bloodstream infections (BSI) with rapidly growing mycobacteria (RGM) resulted in recent nosocomial outbreaks predominantly in immunocompromised patients. A little is known about the clinical implications of RGM BSI with different species.

Methods

We conducted a multicenter retrospective cohort study of patients with RGM BSI from November 2011 to December 2020. Demographic data, clinical presentation, laboratory and radiographic findings and microbiological characteristics were used to tabulate descriptive statistics. We performed a comparative analysis of patients with BSI due to Mycobacterium abscessus complex (MABC) vs. other RGM.

Results

We identified 32 patients with positive blood cultures for RGM, 4/32 (12.5%) were considered to have unclear significance. The most common source for RGM BSI was intravascular catheters (14/28, 50%). Compared to other sources, patients with catheter-related bloodstream infection (CRBSI) received a shorter course of antimicrobial therapy (median [IQR]: one month [0.37–2.25] vs. six months [2–12]), (P = 0.01). The most common species isolated were MABC (12/28, 42.9%), followed by Mycobacterium fortuitum group (6/28, 21.4%) and Mycobacterium chelonae (6/28, 21.4%). Compared to other RGM, MABC BSI was more likely to be secondary to skin and soft tissue infection, associated with longer hospital stay (P = 0.04) and higher death rates despite a higher number of antimicrobial agents used for empirical and directed therapy per patient.

Conclusion

MABC BSI is associated with an overall more resistant profile, longer hospital stay, and higher death rate despite a more aggressive therapy approach.

Screening of Fungi for Antimycobacterial Activity Using a Medium-Throughput Bioluminescence-Based Assay

There is a real and urgent need for new antibiotics able to kill Mycobacteria, acid-fast bacilli capable of causing multiple deadly diseases. These include members of the Mycobacterium tuberculosis complex, which causes the lung disease tuberculosis (TB) as well as non-tuberculous Mycobacteria (NTM) a growing cause of lung, skin, soft tissue, and other infections. Here we describe a medium-throughput bioluminescence-based pipeline to screen fungi for activity against Mycobacteria using the NTM species Mycobacterium abscessus and Mycobacterium marinum. We used this pipeline to screen 36 diverse fungal isolates from the International Collection of Microorganisms from Plants (ICMP) grown on a wide variety of nutrient-rich and nutrient-poor media and discovered that almost all the tested isolates produced considerable anti-mycobacterial activity. Our data also provides strong statistical evidence for the impact of growth media on antibacterial activity. Chemical extraction and fractionation of a subset of the ICMP isolates revealed that much of the activity we observed may be due to the production of the known anti-mycobacterial compound linoleic acid. However, we have identified several ICMP isolates that retained their anti-mycobacterial activity in non-linoleic acid containing fractions. These include isolates of Lophodermium culmigenum, Pseudaegerita viridis, and Trametes coccinea, as well as an unknown species of Boeremia and an isolate of an unknown genus and species in the family Phanerochaetaceae. Investigations are ongoing to identify the sources of their anti-mycobacterial activity and to determine whether any may be due to the production of novel bioactive compounds.

The combination of photodynamic therapy and fractional CO2 laser for mycobacterium marinum infection

Mycobacterium marinum (M. marinum) can cause cutaneous infection. Therapy with active antibiotics for 3 to 6 months is one reasonable treatment. However, it is hard to provide an optimal balance with regard to efficacy and tolerability when the patient is complicated with other diseases. We reported two patients with cutaneous M. marinum infections who were successfully treated with 5-aminolevulinic acid-photodynamic therapy (5-ALA-PDT) combined with fractional CO2 laser ablation. The results of these two cases indicated that PDT in combination with fractional CO2 laser ablation of epidermis could be a therapeutic option for the treatment of skin infections caused by M. marinum.

Non-tuberculous cutaneous mycobacterioses

Non-tuberculous mycobacteriosis, previously known as atypical, anonymous, opportunistic, or unclassified mycobacteriosis, refers to pathogenic mycobacterioses other than those caused by Mycobacterium tuberculosis and Mycobacterium leprae. These mycobacteria are known for their environmental distribution, mainly in water and soil. The incidence of non-tuberculous mycobacteriosis has been increasing in all countries and skin infections are being increasingly studied, mainly with the increase in immunosuppressive conditions and the development of new medications that affect immunological function. In the present article, a detailed narrative review of the literature is carried out to study the main non-tuberculous mycobacteriosis that cause diseases of the skin and appendages. The article also aims to present a historical context, followed by epidemiological, microbiological, and clinical characteristics of these diseases. Practical considerations about the diagnosis and treatment of non-tuberculous mycobacteriosis are detailed.

Disseminated Mycobacterium chelonae infection with Hughes-Stovin syndrome

Mycobacterium chelonae usually causes localized cutaneous infections and abscesses but has the potential to cause disseminated infections, especially in immunocompromised hosts. We report a 27-year-old man with Hughes-Stovin syndrome and catastrophic antiphospholipid syndrome who was on chronic immunosuppressant therapy and developed disseminated M. chelonae infection. To the best of our knowledge, this is the first case report of M. chelonae infection in a patient with Hughes-Stovin syndrome.

Clinical analysis of nontuberculous mycobacterial infection after minimally invasive plastic surgery and cosmetic surgery

OBJECTIVE

To investigate the clinical features, diagnosis, and treatment of nontuberculous mycobacterial infections after minimally invasive plastic surgery and cosmetic surgery, and to provide reference data for the management of affected patients.

METHOD

We retrospectively analyzed 12 cases of nontuberculous mycobacterial infection after minimally invasive plastic surgery and cosmetic surgery in our department from January 2014 to December 2020. The case data included baseline characteristics, morbidity, chronology of patient symptoms, diagnostic results, and treatment outcomes. Disease characteristics were summarized and objectively analyzed.

RESULTS

The 12 patients infected with nontuberculous mycobacteria after plastic surgery and cosmetic surgery received small incision or minimally invasive surgery. The onset time was 5-30 days after surgery, the clinical manifestations were non-specific, and ordinary antibiotics are ineffective.

CONCLUSIONS

Small incisions or minimally invasive plastic surgery and cosmetic surgery have hidden dangers of nontuberculous mycobacterial infection, and the detection and diagnosis are difficult, and the treatment time is long, which requires attention.

Identification of Nontuberculous Mycobacteria in Drinking Water in Cali, Colombia

Nontuberculous mycobacteria (NTM) are ubiquitous microorganisms naturally resistant to antibiotics and disinfectants that can colonize drinking water supply systems. Information regarding the spread of NTM in specifically South America and Colombia is limited. We aimed to identify and characterize NTM present in tap water samples from Cali, Colombia. Drinking water samples and faucet biofilm swabs were collected in 18 places, including the city’s three main water treatment plants (WTPs). Filter-trapped material and eluates (0.45 μm) from swab washes were plated in 7H11 agar plates. Suspected colonies were evaluated microscopically, and NTM species were identified based on the rpoB gene. Antibiotic susceptibility testing was also performed. Fifty percent (9/18) of sampling points were positive for NTM (including two WTPs), from which 16 different isolates were identified: Mycobacterium mucogenicum (8/16), M. phocaicum (3/16), M. chelonae (2/16), M. mageritense (2/16), and M. fortuitum (1/16), all rapidly growing mycobacteria. A susceptibility profile was obtained from 68.75% (11/16) of the isolates. M. chelonae was the most resistant species. All NTM isolated are potentially responsible for human diseases; our findings might provide a baseline for exploring NTM transmission dynamics and clinical characterization, as well as potential associations between NTM species found in drinking water and isolates from patients.

Mycobacterium agri Skin Infection in a Previously Healthy Patient: A Case Study

Nontuberculous mycobacteria infections present mostly pulmonary characteristics. However, the incidence of skin and soft tissue infections caused by nontuberculous mycobacteria has increased in part due to the increased popularity of cosmetic and plastic surgery. Here, we report a case of Mycobacterium agri infection. The patient underwent a one-year course of anti-infection therapy. To the best of our knowledge, this is the first report of a previously healthy patient presenting a skin and soft tissue infection caused by Mycobacterium agri. Clinical personnel should be aware of possible causes of persistent skin and soft tissue infection after cosmetic and plastic surgery.

Clofazimine susceptibility testing of Mycobacterium avium complex and Mycobacterium abscessus: a meta-analysis study

OBJECTIVES

The incidence of infections due to Mycobacterium avium complex (MAC) and Mycobacterium abscessus (MABS) is increasing worldwide. Current antimycobacterial agents are not sufficiently effective against nontuberculous mycobacteria (NTM) and there is a need for new drugs. This study aimed to estimate the overall in vitro activity of clofazimine (CFZ) against MAC and MABS clinical isolates.

METHODS

We systematically searched four databases up to 1 March 2020 to identify relevant studies. Studies were included if they used the Clinical and Laboratory Standards Institute (CLSI) criteria for drug susceptibility testing (DST). We assessed the pooled in vitro CFZ resistance rate in MAC and MABS clinical isolates using a random- effects model. Sources of heterogeneity were evaluated using Cochran's Q and the I² statistic. Potential for publication bias was explored using Begg's and Egger's tests. All analyses were conducted using Stata 14.0.

RESULTS

A total of 20 publications (11 reports for MAC and 15 for MABS) were included. The pooled rates of in vitro resistance to CFZ in clinical isolates of MAC and MABS were 9.0% [95% confidence interval (CI) 3.0-17.0%] and 16.0% (95% CI 4.0-34.0%), respectively. There was no evidence of publication bias.

CONCLUSION

This study reports the frequency of CFZ resistance in clinical isolates of MAC and MABS. According to the results, establishing accurate DST methods for detecting CFZ resistance, performing DST for all NTM isolates to provide effective treatment, and continuous monitoring of drug resistance are suggested for the prevention and control of CFZ-resistant NTM.

Photoinactivation of mycobacteria to combat infection diseases: current state and perspectives

Abstract

The spread of multi-drug-resistant bacterial strains causing serious infectious diseases dictates the development of new approaches to combat these diseases. In addition to drug resistance, the important causative agent of tuberculosis (Mycobacterium tuberculosis (Mtb)) is able to persist asymptomatically in individuals for many years, causing latent forms of tuberculosis. In such a dormant state, Mtb cells are also resistant to known antibiotics. In this regard, photodynamic inactivation (PDI) could be an effective alternative to antibiotics as its action is based on the generation of active forms of oxygen independently on the presence of specific antibiotic targets, thereby inactivating both drug-resistant and dormant bacteria. In this review, we summarise examples of the application of PDI for the elimination of representatives of the genus Mycobacteria, both in vitro and in vivo. According to published results, including photosensitisers in the PDI regime results in a significantly higher lethal effect. Such experiments were mainly performed using chemically synthesised photosensitisers, which need to be transported to the areas of bacterial infections, limiting PDI usage by surface (skin) diseases. In this regard, endogenous photosensitisers (mainly porphyrins) could be used to solve the problem of transportation. In vitro experiments demonstrate the effective application of PDI for mycobacteria, including Mtb, using endogenous porphyrins; the intracellular contents of these substances can be elevated by administration of 5-aminolevulenic acid, a precursor of porphyrin synthesis. Photodynamic inactivation can also be used for dormant mycobacteria, which are characterised by high levels of endogenous porphyrins. Thus, PDI can effectively eliminate drug-resistant mycobacteria. The exploitation of modern light-transmitting techniques opens new possibilities to use PDI in clinical settings.

Key points

•The potential effects of photodynamic inactivation of mycobacteria are critically reviewed.

•Approaches to photoinactivation of mycobacteria using exogenous and endogenous photosensitisers are described.

•Prospects for the use of photodynamic inactivation in the treatment of tuberculosis are discussed.

Occurrence of Nontuberculous Mycobacteria, Salmonella, Listeria monocytogenes, and Staphylococcus aureus in Artisanal Unpasteurized Cheeses in the State of Michoacan, Mexico

ABSTRACT

This study investigated the presence of nontuberculous mycobacteria (NTM) for the first time in two types of unpasteurized fresh cheese produced in the state of Michoacan, Mexico. We tested for this pathogen, along with the others, to broaden the study of microbiological quality in 60 samples of cheese, 30 fresh and 30 Adobera, which were collected from six artisanal cheese factories (ACFs). The hygienic conditions of these establishments and the practices of cheese manufacture were generally poor. Although Mycobacterium bovis was not detected, four cheese samples harbored NTM isolates. The four NTM isolates were identified using three molecular markers (hsp65, rrs, and rpoB genes) that corresponded to Mycolicibacterium fortuitum (n = 3) and Mycolicibacterium mageritense (n = 1). All 60 cheese samples analyzed had unsatisfactory microbiological quality according to the Mexican Official Guideline. Regarding fresh cheeses, all 30 samples analyzed were positive for aerobic mesophilic bacteria, total coliforms, fecal coliforms, and yeasts and molds. Escherichia coli and Staphylococcus aureus were present in 23 and 21 samples, respectively. Listeria monocytogenes was identified in a sample and was isolated from a bulk milk tank in the same ACF. With regard to Adobera cheeses, all samples were positive for aerobic mesophilic bacteria, total coliforms, fecal coliforms, yeasts and molds, and S. aureus. E. coli was isolated from 28 samples. Salmonella was isolated from a sample and from a wooden shovel used in the manufacture of the cheeses in the same ACF. Thus, the consumption of unpasteurized fresh cheese may represent a public health risk. Because of this, health authorities should enforce the legislation that forbids the processing of cheese with unpasteurized milk and encourage producers to follow good manufacturing practices from original ingredients, through the production process of the cheese, to its sale to assure a safe product.

HIGHLIGHTS

Granulomas in Dermatopathology: Principal Diagnoses - Part 2

Part 2 of this series on granulomatous diseases focuses on skin biopsy findings. Whereas the first part treated noninfectious conditions (metabolic disorders and tumors, among other conditions), this part mainly deals with various types of infectious disease along with other conditions seen fairly often by clinical dermatologists.