Nontuberculous mycobacterial infections of the skin: A retrospective study of 25 cases

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.

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 .

Isolation of potential zoonotic Mycobacterium spp. from diseased freshwater angelfish (Pterophyllum scalare) from an aquarium

Abstract Nontuberculous mycobacteria infection is one of the most common chronic bacterial diseases in ornamental aquarium fish and appears to be directly related to stressful husbandry practices. Furthermore, it also represents zoonotic potential. Here we present the isolation and characterization of non-tuberculous mycobacteria from diseased freshwater angelfish (Pterophyllum scalare) in São Paulo, Brazil. Nine discarded breeding females with signs of disease were evaluated. The fish exhibited lethargy, loss of appetite, cachexia, skin ulcers, and exophthalmia. At necropsy, four fishes presented macroscopic granulomas in the spleen. Mycobacterium chelonae, M. fortuitum, M. gordonae, M. intracellulare and M. peregrinum were isolated and identified by hsp65 PCR restriction analysis. Histopathological analysis revealed microscopic lesions compatible with mycobacteriosis, and Mycobacterium bacillus were observed by Ziehl-Neelsen stain. Notably, all Mycobacterium species identified in this study have already been reported in human patients; therefore, diseased animals may be a source of infection for people who handle fish and aquariums.

Disseminated Cutaneous Mycobacterium chelonae Infection in an Immunocompetent Patient

We present a case report on disseminated cutaneous Mycobacterium chelonae infection with a sporotrichoid pattern in an immunocompetent patient. The aim of this report is to contribute to the existing knowledge on the clinical presentation and management of this uncommon presentation.

Diagnosis and therapy of Mycobacterium marinum: a single-center 21-year retrospective analysis

BACKGROUND AND OBJECTIVES

In Europe, infections with Mycobacterium (M.) marinum are rare. We conducted a retrospective single-center study to assess the clinical spectrum of M. marinum infection and its diagnosis, treatment and outcome under real-world conditions.

PATIENTS AND METHODS

Eighteen patients presenting with M. marinum infections between 1998 and 2018 were identified in the data warehouse of the University Hospital Würzburg and considered for detailed analysis.

RESULTS

Twelve patients reported aquatic exposure. In 16/18 cases the upper extremities were affected. No invasive infections were detected. Mean time to diagnosis was 15 weeks. Histology revealed granulomatous inflammation in 14 patients while mycobacterial cultures were positive for M. marinum in 16 cases. Most patients received antibiotic monotherapy (14/18) while combination therapy was administered in four cases. Treatment (with a median duration of 10 weeks) was successful in 13 patients. Five patients were lost to follow-up.

CONCLUSIONS

Our retrospective analysis of M. marinum infections at a German tertiary referral center revealed a considerable diagnostic delay and the relevance of microbiological culture, PCR and histology for diagnosis. Monotherapy with clarithromycin (rather than doxycycline) appeared as a reasonable treatment option while immunosuppressed or -compromised patients and those with extended disease received combination therapy.

Cutaneous nontuberculous mycobacterial infections in Japan: Review of the Japanese literature

Nontuberculous mycobacteria cause a wide range of infections, including cutaneous infections, in both immunocompromised and immunocompetent patients. Although pulmonary nontuberculous mycobacterial infections have increased significantly in Japan in recent years, there is less evidence on clinical and microbiological characteristics of cutaneous nontuberculous mycobacterial infections in Japan. We reviewed 86 Japanese cases reported between July 2016 and November 2021 and analyzed them in conjunction with the eight patients from our institution who were diagnosed with cutaneous nontuberculous mycobacterial infections by culture between 2015 and 2021. In the aggregate series, the average patient age was 60 years, and the ratio of immunocompromised hosts was 53%, both of which were higher than those in previous reports from other countries. No female predominance was observed, unlike in pulmonary nontuberculous mycobacteria infections. Rapidly growing mycobacteria accounted for 58% of the cases (n = 54), whereas slowly growing mycobacteria for 43% (n = 40). Mycobacterium marinum (also known as Mycobacteroides marinum) (n = 20, 21%) was the most common cause, followed by Mycobacterium chelonae (n = 18, 19%), Mycobacterium abscessus (also known as Mycobacteroides abscessus) (n = 15, 16%), and Mycobacterium ulcerans (n = 11, 12%). While clinical appearance was variable, M ulcerans infections usually presented with ulcers, while nodules were common among infections caused by M chelonae and M marinum. Disseminated infections involving multiple organs were observed in 23 patients (24%). Thirty-two cases (30%) were preceded by exposure, including raising or handling fish, trauma, and invasive medical procedures. Most patients were treated with more than two antibiotics and responded to therapy.

Quinoxaline-based efflux pump inhibitors restore drug susceptibility in drug-resistant nontuberculous mycobacteria

Nontuberculous mycobacteria (NTM) comprise several ubiquitous, environmentally localized bacteria that may be responsible for serious human diseases. NTM-associated pulmonary infections largely affect individuals with underlying respiratory disease or chronic disease and immunosuppressed patients. Mycobacterium simiae and M. abscessus are two NTMs responsible for lung disease in immunocompetent and immunocompromised individuals. In this study, two NTM strains were isolated from two patients admitted to an Italian hospital and were identified as M. simiae and M. abscessus. The two NTMs were tested for drug susceptibility against different antibiotics. To restore drug susceptibility, a new series of 2-aryl-3-phenoxymethyl-quinoxaline derivatives (QXs) was designed, synthesized, and investigated as efflux pump inhibitors (EPIs) against two clinical isolates of the above-cited NTMs, evaluating how EPIs can influence the drug minimal inhibitory concentration values and, therefore, the activity. The different\ resistance levels tracked in the clinical strains were reduced by EPIs, and in several cases, the susceptibility was completely restored. QXs also resulted as potential chemical probes to be used in drug susceptibility tests to identify the resistance origin when detected.

Mycobacterium smegmatis Skin Infection Following Cosmetic Procedures: Report of Two Cases

Mycobacterium smegmatis is an acid-fast bacillus of rapidly growing mycobacteria (RGM) of nontuberculous mycobacteria (NTM). M. smegmatis was considered nonpathogenic to humans until 1986, when the first patient was linked to the infection. To date, fewer than 100 cases have been reported in the literature, mainly related to various surgical procedures. Herein, we report two immunocompetent patients who acquired M. smegmatis infection following cosmetic procedures. Due to the rarity of M. smegmatis infection in routine clinical practice, it is challenging for medical providers to diagnose and treat patients with M. smegmatis infection. M. smegmatis infection should be considered for patients with chronic skin and soft tissue infections at the injection site or surgical site following cosmetic procedures. Histological findings, pathogen identification by molecular testing or bacterial culture are required to make a definitive diagnosis. Medical providers should raise awareness of M. smegmatis infection for patients with chronic skin and soft tissue infections after cosmetic procedures. Stringent sterile procedures for surgical instruments, supplies, and environments should be enforced.

5-aminolevulinic acid-photodynamic therapy ameliorates cutaneous granuloma by killing drug-resistant Mycobacterium marinum

BACKGROUND

Although 5-aminolevulinic acid photodynamic therapy (ALA-PDT) has been extensively used to treat various skin diseases, its application to the treatment of cutaneous infection caused by Mycobacterium marinum (M. marinum), especially by drug-resistant M. marinum, is still unclear.

OBJECTIVES

We evaluated the efficacy of ALA-PDT on M. marinum in a mouse infection model and tested its killing effect on M. marinum in vitro. We also investigated the clinical effect of ALA-PDT on cutaneous granuloma caused by drug-resistant M. marinum.

MATERIALS AND METHODS

A total of 9 M. marinum strains isolated from patients were tested for anti-mycobacterial susceptibility. The effects of ALA-PDT on M. marinum in vitro and in mice model were investigated. Therapeutic efficacy was further assessed in two patients with cutaneous granuloma caused by drug- resistant M. marinum.

RESULTS

We demonstrated that ALA-PDT directly killed M. marinum in vitro. The cutaneous lesions on mouse paws caused by M. marinum were fully recovered 4 weeks after the ALA-PDT treatment. ALA-PDT was also effective in two patients with cutaneous infection caused by drug-resistant M. marinum. The level of intracellular ROS in M. marinum treated with ALA-PDT was significantly higher than that of M. marinum alone.

CONCLUSIONS

The results suggest that ALA-PDT is effective in treating M. marinum cutaneous infections by releasing more reactive oxygen species to kill M. marinum directly, and these effects are independent of systemic immune responses. The data highlights that ALA-PDT is a promising therapeutic choice for treatment of M. marinum cutaneous infections, especially drug-resistant M. marinum infections.

Case Series and Review of the Literature of Mycobacterium chelonae Infections of the Lower Extremities

Mycobacterium chelonae infections involving the lower extremities are rare clinical entities that present a diagnostic challenge given its diverse clinical presentations ranging from superficial (e.g., cellulitis, painful vesicular lesions) to deep (e.g., tenosynovitis) infections. We present 1 cases of M chelonae infections of the feet diagnosed 6 to 12 months after initial symptoms representing the difficulty of diagnosing this condition. Both cases were successfully managed with aggressive surgical debridement and long durations of antibiotic therapy with long-term care. A comprehensive review of the literature of M chelonae infections of the lower extremities was performed to provide summary data on the presenting symptoms, examination findings, predisposing conditions, and management approaches of this rare, but emerging clinical entity. Our cases and comprehensive review serve to raise awareness of atypical mycobacterial infections, including M chelonae, and advocate for the early consideration of mycobacterial cultures in the diagnostic workup of chronic lower extremity infections especially in the setting of poor initial response to standard antibacterial therapies.

Infectious Tenosynovitis of the Tibialis Anterior Due to Mycobacterium chelonae After Intravenous Heroin Injection

Mycobacterium chelonae is a ubiquitous Gram-positive, acid-fast, non-spore-forming bacterium commonly encountered in nature associated with aquatic animals, soil, and water, including tap water. Nontuberculous mycobacterial tenosynovitis infections caused by M. chelonae in the lower extremity are uncommon, leading to a paucity of literature documenting the diagnosis and treatment of such cases. This report is of a 65-year-old male patient who was found to have an M. chelonae infection along the tibialis anterior tendon after injecting himself with heroin into the dorsal foot veins. This review covers the diagnosis and treatment as well as a case report on the outcome of infectious tenosynovitis of the tibialis anterior associated with M. chelonae. To date, this is the only reported case of tibialis anterior infectious tenosynovitis caused by M. chelonae after intravenous heroin injection.

Small vessel vasculitis secondary to Mycobacterium chelonae

Mycobacterial infection can be seriously debilitating and challenging to diagnose. The infection can mimic vasculitis associated with positive anti-neutrophilic cytoplasmic autoantibodies (ANCA). This clinical scenario is exemplified with a well-studied case of a 63-year-old Caucasian man with uncontrolled diabetes and ulcerative colitis on immunosuppressive agents. The patient was hospitalized for 3 months with worsening painful hand ulcerations. Primary vasculitis was first suspected, but the patient was later diagnosed with vasculitis secondary to Mycobacterium chelonae infection. Report includes discussion on sequence of testing which led to the diagnosis. After proper diagnosis and change to proper antibiotics, the patient's vasculitis improved over time. It is our hope that this report further raises awareness of mycobacterial infection as a mimicker of vasculitis. We also provide a review of relevant literature on non-tuberculosis mycobacterial (NTM) infection including a review of 22 articles and 12 cases found in the literature. The salient features of the literature review include that 10 of the 12 cases were patients who had risk factors of immunosuppression due to medications, and all patients were infected by mycobacterium causing skin vasculitis. After given the proper directed antibiotic treatment, 11 of the 12 patients had a reported improved outcome.

Cutaneous nontuberculous mycobacterial infection in Thailand: A 7-year retrospective review

A remarkable increase in the prevalence of cutaneous nontuberculous mycobacterial (NTM) infection has occurred worldwide. However, updated data regarding cutaneous NTM infection in Thailand is limited.This study aim to describe the clinical manifestations, pathogenic organism, and prognostic factors of cutaneous NTM infections among patients living in Thailand.The electronic medical records of all patients with confirmatory diagnosis of cutaneous NTM infection from either positive cultures or polymerase chain reaction were retrospectively reviewed at a university-based hospital.From 2011 to 2017, a total of 88 patients with a confirmed diagnosis of cutaneous NTM infection were included. Mycobacterium abscessus was the most common pathogens followed by M haemophilum and M marinum (61.4%, 10.2%, and 8.1%, respectively). Nodule and plaque were 2 most common lesions (26.4% and 25.5%, respectively) and lower leg is the most common site of involvement (50.9%). The majority of patients presented with single lesion (67%). Seven patients (7.9%) had history of surgical procedure and/or cosmetic injection before the development of lesion and all pathogenic organisms in this group were rapidly growing mycobacteria. Sweet's syndrome and erythema nodosum were the 2 most common reactive dermatoses, presented in 3.4% and 2.3%, respectively. The majority of patients infected with cutaneous M haemophilum infections were immunocompromised and lacked history of preceding trauma (77.8%). Patients with cutaneous NTM that receiving less than 3 medications was associated with higher disease relapse (odds ratio 65.86; P = .02).M abscessus is the most common pathogen of cutaneous NTM infection in Thailand. The prevalence of M haemophilum is increasing and should be particularly cautious in immunocompromised patients. Rapidly growing mycobacteria should be suspected in all cases of procedure-related cutaneous NTM. We recommend at least 3 antibiotics should be considered for cutaneous NTM infection to reduce the rate of relapse.

Comparison between organismal staining on histology and tissue culture in the diagnosis of cutaneous infection: A retrospective study

BACKGROUND

In instances of suspected cutaneous infection, the standard of care includes obtaining skin biopsy specimens for histology and tissue culture. Few studies have compared the clinical utility of each test.

OBJECTIVE

To assess the concordance of results between tissue culture and histology, as well as the clinicopathologic features that may influence the diagnostic yield of each test.

METHODS

A retrospective review of all patients who underwent skin biopsy for histology and tissue culture at New York University from 2013 through 2018.

RESULTS

Of 179 patients, 10% had positive concordance, 21% had positive tissue culture only, and 7% had positive histology only. We calculated a kappa correlation coefficient of 0.25 between histology and tissue culture (reference, 0.21-0.39 indicates minimal agreement). Histology exhibited higher sensitivity in detecting fungi, whereas tissue culture was more sensitive in identifying Gram-negative bacteria. Antimicrobial use before biopsy led to significantly fewer positive cultures (37.5% vs 71%; P = .023) in patients ultimately diagnosed with infection.

LIMITATIONS

This study was conducted at a single institution, thereby restricting its broad applicability. The lack of a validated criterion standard to diagnose infection also limits interpretation of the results.

CONCLUSION

Tissue culture and histopathology often yield discordant results. Dermatologists should recognize specific limitations, yet high clinical utility in special circumstances, of tests when approaching cases of suspected infection.

Fishing for a Diagnosis, the Impact of Delayed Diagnosis on the Course of Mycobacterium marinum Infection: 21 Years of Experience at a Tertiary Care Hospital

Background

Mycobacterium marinum is a common but underreported mycobacterial infection. We conducted a large retrospective study to determine risk factors and describe the therapeutic interventions and outcomes in patients with uncomplicated and complicated M. marinum infection.

Methods

Culture-confirmed M. marinum infection cases were identified from the Mayo Clinic Clinical Mycology Laboratory from January 1998 to December 2018. Complicated M. marinum infection was defined as the presence of tenosynovitis, septic arthritis, or osteomyelitis. Differences in complicated vs uncomplicated M. marinum infections were analyzed using statistical comparisons.

Results

Twelve cases had a complicated M. marinum infection. Patients with a complicated infection were older (64.3 ± 11.1 vs 55.8 ± 14.5; P = .03), had longer duration of symptoms (5 vs 3 months; P = .011), and had more surgical debridements (1 vs 0; P < .001). Length of treatment and number of drugs used were not statistically significant. Complicated M. marinum cases received more medications (2 vs 1; P = .263) and were treated longer (5.7 vs 3.5 months; P = .067). Antibiotic susceptibilities were performed in 59% of the patients. All isolates were susceptible to clarithromycin. From the tetracyclines, doxycycline had a better susceptibility pattern.

Conclusions

M. marinum infection is an important cause of skin and soft tissue infection. Poor water exposure documentation, unusual clinical presentation, and empiric antibiotic treatment before definitive M. marinum diagnosis often contribute to a delayed diagnosis. Complicated M. marinum cases had longer duration of symptoms and more surgical debridements. No difference in the number of drugs used or clinical outcome was observed.

Diagnosis of Mycobacterium abscessus/chelonae complex cutaneous infection: Correlation of tissue culture and skin biopsy

Mycobacterium abscessus and M. chelonae belong to the rapid-growing nontuberculous mycobacteria (NTM) group, which are defined by their ability to form visible colonies on agar within 7 days of subculture. Cutaneous infections by this complex show a heterogeneous clinical presentation with varied histopathologic findings. However, the presence of vacuoles in many specimens has been reported as a specific histologic finding. Herein, we correlate the histopathology of patients with tissue-culture positive M. abscessus/M. chelonae complex in order to identify features that may prompt a rapid categorization of the infectious etiology. The cohort includes 33 skin punch biopsy specimens from 28 patients who had associated positive tissue cultures. The most frequent clinical presentation was a single or multiple nodule. Twenty-seven specimens (81.81%) were found to have vacuoles. The observation of certain histologic features (ie, polymorphonuclear microabscesses and epithelioid granuloma formation) should raise the possibility of infection by NTM. In addition to these findings, we believe the presence of vacuoles in the dermal and subcutaneous inflammation should raise suspicion for NTM.

Cutaneous Mycobacterium Marinum Infection (Fish Tank Granuloma) in a Renal Transplant Recipient: Case Report and Literature Review

Atypical mycobacterioses are unusual infections of the skin and other organs caused by non-tuberculous mycobacteria. Fish tank granuloma and swimming pool granuloma are two forms of atypical mycobacterioses caused by Mycobacterium marinum. So far, only a few cases of these infections have been reported in organ transplant patients, and these usually are more severe when compared with atypical mycobacterioses in immunocompetent hosts. We report a kidney transplant patient with a rather mild form of atypical mycobacteriosis (fish tank granuloma) who responded well to treatment with doxycycline and will provide a review of all similar cases reported in the literature.

Fish tank granuloma: An emerging skin disease in Iran mimicking Cutaneous Leishmaniasis

OBJECTIVE

Mycobacterium marinum causes a rare cutaneous disease known as fish tank granuloma (FTG). The disease manifestations resemble those associated with Cutaneous Leishmaniasis (CL). The aim of this study was to determine whether FTG was the cause of cutaneous lesions in patients who were referred to the Parasitology laboratory of Imam Reza Hospital in Mashhad to be investigated for CL.

MATERIALS/METHODS

One hundered patients, clinically diagnosed with CL between April 2014 and March 2015, were included in this study. Ziehl-Neelsen staining was performed to identify acid-fast Mycobacterium in addition to bacterial cultures using Löwenstein-Jensen medium. Skin lesion samples were also collected and kept on DNA banking cards for PCR testing.

RESULTS

Twenty-nine of the 100 individuals with skin lesions, and therefore suspected of suffering from CL, tested positive for Mycobacterium marinum by PCR. Of these, 21 (72.4%) were male and 8(27.6%) were female. In 97% of these cases the lesions were located on hands and fingers. These patients had a history of manipulating fish and had been in contact with aquarium water. A sporotrichoid appearance was observed in 58.6% of the patients with mycobacterial lesions; 67% of patients had multiple head appearance.

CONCLUSION

Patients suspected to have CL and who test negative for CL could be affected by FTG. Therefore, after obtaining an accurate case history, molecular diagnosis is recommended for cases that give a negative result by conventional methods.

Cutaneous nontuberculous mycobacteria infections: A retrospective case series of 78 patients from the Texas Gulf Coast region

BACKGROUND

The incidence of cutaneous nontuberculous mycobacteria (NTM) infections is increasing. These infections are a diagnostic and therapeutic challenge.

OBJECTIVE

We investigated the clinical features, diagnosis, and management of cutaneous NTM infections.

METHODS

A retrospective case series studied 78 patients from a Gulf Coast tertiary referral center diagnosed with cutaneous NTM infection by culture or stain of a skin biopsy specimen.

RESULTS

A history of trauma, procedure, or environmental exposure was common. The mean time between the initial evaluation and diagnosis was 12 weeks. Only 15% of acid-fast bacillus-positive cultures had a positive acid-fast bacillus smear, and only 43% of those accompanied by skin biopsy specimen had a positive Fite stain. Immunosuppressed patients were more likely to have a positive Fite stain. Treatment included surgery and multiple antibiotics. Immunosuppressed patients and Mycobacterium abscessus group infections were more likely to have persistent disease.

LIMITATIONS

M chelonae and M abscessus isolates were indistinguishable and therefore were reported together. Five cases were not confirmed by culture.

CONCLUSIONS

Even with clinical suspicion, the diagnosis of NTM infection can be difficult. Results of acid-fast bacillus smears and special stains are frequently negative. Antibiotic resistance is common. Multidrug treatment is often required, and surgical therapy may be needed.

Cutaneous Infections Due to Nontuberculosis Mycobacterium: Recognition and Management

Nontuberculous mycobacteria (NTM) are a diverse group of organisms that are ubiquitous in the environment, and the incidence of cutaneous infections due to NTM has been steadily increasing. Cutaneous infections due to NTM can be difficult to diagnose, due to their wide spectrum of clinical presentations and histopathological findings that are often nonspecific. A variety of modalities including tissue culture and polymerase chain reaction (PCR) assays may be necessary to identify the organism. Treatment can also be challenging, as it can depend on multiple factors, including the causative organism, the patient's immunological status, and the extent of disease involvement. In this review, we discuss the common presentations of cutaneous NTM infections, diagnostic tools, and treatment recommendations. A multi-disciplinary approach that involves good communication between the clinician, the histopathologist, the microbiologist, and infectious disease specialists can help lead to successful diagnosis and management.

Atypical clinical and laboratory features of fish-tank granuloma: A case report

We report a case of cutaneous Mycobacterium marinum infection with the unusual reported features of pruritus and paresthesia. In addition, we report a lack of in-vivo response to antibiotics based on in-vitro susceptibility testing.

Cutaneous atypical mycobacteriosis with sporotrichoid clinical presentation caused by automotive accident

Atypical mycobacterial infections are caused by mycobacteria other than those from the M. tuberculosis complex and M. leprae. Its incidence has increased progressively, with considerable increase of scientific publications on the subject. Only 10% of the cases present with cutaneous infections, most of them related to surgical interventions and aesthetic procedures. We present a case of mycobacteriosis due to automotive accident that presented a diagnostic challenge due to its clinical presentation with lesions of sporotrichoid progression in the lymphatic system.

Cutaneous Nontuberculous Mycobacterial Infections in Alberta, Canada: An Epidemiologic Study and Review

Background:

Cutaneous infections caused by nontuberculous mycobacteria (NTM) occur infrequently. Nonetheless, the incidence of NTM infections is reported to be increasing. In Canada, cutaneous NTM infections have not been well described.

Objectives:

A database review from 2006 to 2016 was done to assess species frequency, incidence, and trends of the most common cutaneous NTMs in the province of Alberta, Canada. We also reviewed major diagnostic and epidemiologic aspects of NTM cutaneous infections with a focus on Mycobacterium marinum.

Results:

A database search identified 244 cases of NTM infections. Mycobacterium avium-intracellulare complex had the highest incidence, causing 64% of cases. Rapid growers ( Mycobacterium abscessus, Mycobacterium chelonae, Mycobacterium fortuitum) caused 23% and M marinum 13%. Information on infection site was available for 117 cases. There was no difference noted in sex distribution; however, differences in age groups between species were noted.

Conclusions:

The incidence of NTM cutaneous infections in Alberta, Canada, was reported for the first time and the incidence of M marinum was found to be similar to that reported in the worldwide literature. Patients’ age groups were different between species. Knowledge of the unique microbiological features of NTMs and the role of the diagnostic laboratory are important.

Mycobacterium marinum infections in Denmark from 2004 to 2017: A retrospective study of incidence, patient characteristics, treatment regimens and outcome

Mycobacterium marinum (M. marinum) is a slowly growing nontuberculous mycobacterium. The incidence of M. marinum infections in Denmark is unknown. We conducted a retrospective nationwide study including all culture confirmed cases of M. marinum from 2004 to 2017 in Denmark. All available medical records were reviewed. Demographics, clinical characteristics, and treatment regiments were analyzed. Fifty-five patients were identified, 40 (72.7%) were men with a median age of 50 years. Aquatic exposure was reported by 48 (90.6%) of the patients. Site of infection was upper extremities in 49 (92.5%) patients and 49 (92.5%) had superficial infection. The median time from symptom presentation to diagnosis was 194 days. All patients received antibiotics. Median time of treatment duration among all patients was 112 days. Treatment outcome was classified as improved in 40 (75%), improved with sequela in 4 (7.6%) patients and only 3 patients (3.8%) were classified as failed. Infection with M. marinum is rare and there is a long delay from symptom manifestation to diagnosis. The infection is predominantly related to aquatic exposure. M. marinum should be a differential diagnose in patients with slow-developing cutaneous elements and relevant exposure. Treatment outcomes are overall good and severe sequela are rare.

Strategies to Mitigate a Mycobacterium marinum Outbreak in a Zebrafish Research Facility

In 2011, the zebrafish research facility at the University of Oregon experienced an outbreak of Mycobacterium marinum that affected both research fish and facility staff. A thorough review of risks to personnel, the zebrafish veterinary care program, and zebrafish husbandry procedures at the research facility followed. In the years since 2011, changes have been implemented throughout the research facility to protect the personnel, the fish colony, and ultimately the continued success of the zebrafish model research program. In this study, we present the history of the outbreak, the changes we implemented, and recommendations to mitigate pathogen outbreaks in zebrafish research facilities.

Cutaneous Mycobacterium gordonae infection in an elderly diabetic returned traveller

Mycobacterium gordonae, a low pathogenicity organism, is rarely implicated in skin and soft tissue infections. We present a 77-year-old returned diabetic traveler from rural Sudan with cutaneous M. gordonae infection. Several months of ciprofloxacin, rifampin and ethambutol led to resolution of his plaque, without signs of recurrence at 6-month follow-up.

Mycobacteria in aquarium fish: results of a 3-year survey indicate caution required in handling pet-shop fish

Fish are commonly infected with non-tuberculous mycobacteria (NTM), which should be regarded as potential pathogens when handling aquarium fish and equipment. This study examined 107 aquarium fish from pet shops. Cultivation of the fish samples using different selective media was conducted for identification of NTM. Isolates were identified using the GenoType Mycobacterium common mycobacteria and additional species assays, sequencing of the 16S rRNA and rpoB genes, and real-time PCR assay for identification of Mycobacterium (M.) marinum. Among the investigated fish, 79.4% (85/107) were positive for mycobacteria, with 8.2% (7 of 85) having two mycobacterial species present. Among the positive fish, the common pathogens M. marinum, Mycobacterium fortuitum (M. fortuitum group) and Mycobacterium chelonae were identified in approx. 90% of fish and other NTM species in 10%, including Mycobacterium peregrinum/septicum, Mycobacterium gordonae, Mycobacterium arupense, Mycobacterium kansasii, Mycobacterium ulcerans and Mycobacterium setense. The well-known human pathogen M. marinum was present in 10.6% of the positive fish (9 of 85). The species of mycobacteria identified in the study are not only recognized as aquarium fish pathogens, but can also cause pathology in humans. Microbiological and clinical communities should therefore be sensitized to the role of NTM in infections associated with exposure to aquarium fish.

Clinical and histopathological features of cutaneous nontuberculous mycobacterial infection: a review of 13 cases

BACKGROUND

The incidence of cutaneous nontuberculous mycobacterial (NTM) infection has increased in recent decades because of widespread use of immunosuppressive therapy and better detection methods. The histopathology of cutaneous NTM infection is not pathognomic and the organisms are slow and difficult to culture, making diagnosis challenging.

METHODS

We reviewed the clinical and histopathological features of 13 cases of cutaneous NTM infection, and performed panmycobacterial polymerase chain reaction (PCR) on the paraffin blocks.

RESULTS

The immunocompetent patients presented with localized lesions on the extremities, whereas the immunocompromised patients presented with disseminated cutaneous lesions. The histopathology in immunocompetent patients was characterized by pseudoepitheliomatous epidermal hyperplasia, intraepithelial abscesses, transepidermal elimination and dermal granulomatous inflammation accompanied by necrosis and suppuration. The immunocompromised patients showed suppurative inflammation with little granuloma formation and numerous acid-fast bacilli. Paraffin block PCR was positive in 4 of 13 cases (31%), whereas culture was positive in 11 of 13 cases (85%).

CONCLUSION

The aforementioned histological features should help in diagnosing cutaneous NTM infection when combined with clinical and microbiological correlation. In our study, we did not find paraffin block PCR to be superior to conventional culture in detecting cutaneous NTM infection.

Mycobacterium fortuitum infection of the scalp after a skin graft

Mycobacterium fortuitum is a non-tuberculous mycobacterium found in the soil and water of most regions of the world, and it can cause disease in immunocompetent and immunocompromised hosts. We present a 52-year-old man who developed a scalp abscess under a free flap for cranium coverage after a motor vehicle accident. Culture of material drained from the abscess grew M. fortuitum.

Nontuberculous mycobacteria in fistula-in-ano: A new finding and its implications

OBJECTIVE/BACKGROUND

Nontuberculous mycobacteria (NTM) are not known to be associated with fistula-in-ano. NTM was detected in three fistula-in-ano patients in our series. In this study, related data was reviewed to find the mycobacterial disease in patients in our database.

METHODS

In this study, 311 consecutive fistula-in-ano patients operated over 2years were analyzed. The histopathology of anal fistula tract epithelial lining of every operated patient was analyzed and other tests (real-time-polymerase chain reaction [RT-PCR], GeneXpert, and mycobacterial culture) were conducted in patients with high index of suspicion of having mycobacterial disease.

RESULTS

Two patients had histopathological features suggestive of mycobacterial disease. Of these, one patient had NTM and the other had Mycobacterium tuberculosis (MTB) on RT-PCR. Four patients had normal histopathology features but tested positive on RT-PCR (2 each for NTM and MTB). Therefore, a total of six patients were tested for mycobacterial disease (3 each for NTM and MTB). Mycobacterium culture was performed in two patients (both NTM) but the result was negative. Five of six patients (NTM=2, MTB=3) presented with delayed recurrences after operation (6-18months after complete healing).

CONCLUSION

NTM can cause fistula-in-ano. It could be an undiagnosed contributory factor in fistula recurrence. Mycobacterial disease (both tuberculous and nontuberculous) may be associated with delayed recurrence of fistula. RT-PCR is highly sensitive and can differentiate between NTM and MTB. It should perhaps be performed in all recurrent and refractory cases.

The Infectious and Noninfectious Dermatological Consequences of Flooding: A Field Manual for the Responding Provider

Meteorological data show that disastrous floods are increasingly frequent and more severe in recent years, perhaps due to climatic changes such as global warming. During and after a flood disaster, traumatic injuries, communicable diseases, chemical exposures, malnutrition, decreased access to care, and even mental health disorders dramatically increase, and many of these have dermatological manifestations. Numerous case reports document typical and atypical cutaneous infections, percutaneous trauma, immersion injuries, noninfectious contact exposures, exposure to wildlife, and exacerbation of underlying skin diseases after such disasters as the 2004 Asian tsunami, Hurricane Katrina in 2005, and the 2010 Pakistan floods. This review attempts to provide a basic field manual of sorts to providers who are engaged in care after a flooding event, with particular focus on the infectious consequences. Bacterial pathogens such as Staphylococcus and Streptococcus are still common causes of skin infections after floods, with atypical bacteria also greatly increased. Vibrio vulnificus is classically associated with exposure to saltwater or brackish water. It may present as necrotizing fasciitis with hemorrhagic bullae, and treatment consists of doxycycline or a quinolone, plus a third-generation cephalosporin and surgical debridement. Atypical mycobacterial infections typically produce indolent cutaneous infections, possibly showing sporotrichoid spread. A unique nontuberculous infection called spam has recently been identified in Satowan Pacific Islanders; combination antibiotic therapy is recommended. Aeromonas infection is typically associated with freshwater exposure and, like Vibrio infections, immunocompromised or cirrhotic patients are at highest risk for severe disease, such as necrotizing fasciitis and sepsis. Various antibiotics can be used to treat Aeromonas infections. Melioidosis is seen mainly in Southeast Asia and Australia, particularly in rice farmers, and can remain latent for many years before presenting as the host's immunocompetence wanes. It can present with a variety of skin findings or as a nonspecific febrile illness, and preferred treatment consists of ceftazidime or a carbapenem with trimethoprim/sulfamethoxazole (TMP/SMX) for 2 weeks, then continuing TMP/SMX for at least 3 months. Leptospirosis is a waterborne zoonosis that is often prevalent after heavy rains or flooding. Different forms exist, including Fort Bragg fever, which produces a distinctive erythematous papular rash on the shins. Doxycycline is often sufficient; however, volume and potassium repletion may be necessary if renal involvement exists. Chromobacterium violaceum infection may occur after open skin is exposed to stagnant or muddy water. Cultured colonies produce a unique violacein pigment, and treatment typically consists of a carbapenem. Both typical and atypical fungal infections are increased in the flooding disaster scenario, such as dermatophytosis, chromoblastomycosis, blastomycosis, and mucormycosis. Appropriate antifungals should be used. In addition, land inundated with water expands the habitat for parasites and/or vectors, thus increased vigilance for regional parasitic infections is necessary after a flood. Lastly, noninfectious consequences of a flooding disaster are also common and include miliaria, immersion foot syndromes, irritant and allergic contact dermatitis, traumatic wounds and animal bites, and arthropod assault, as well as exacerbation of existing skin conditions such as atopic dermatitis, psoriasis, and alopecia areata due to increased stress or nonavailability of daily medications.

Pediatric Cutaneous Nontuberculous Mycobacterium Infections in Singapore

BACKGROUND

Nontuberculous mycobacterium (NTM) infections are rare in children, with limited published studies. The course of the disease can be variable and there are no accepted treatment guidelines for the management of NTM infections in children.

OBJECTIVE

To review a cohort of pediatric patients admitted to a tertiary pediatric hospital in Singapore for cutaneous NTM infections.

METHODS

A retrospective review was performed of all children admitted to KK Women's and Children's Hospital with cutaneous NTM infections from 2002 to 2012.

RESULTS

Sixty-seven patients with positive NTM cultures from various body sites were identified. Eight of the 67 patients (11.9%) presented with cutaneous NTM without evidence of systemic involvement. The mean age at diagnosis for these eight patients was 10 years (range 5-21 yrs). Mycobacterium abscessus was the most common NTM isolated (five patients), followed by Mycobacterium hemophilium (two patients) and Mycobacterium kansasii (one patient). Most patients presented with isolated skin abscesses. Two patients were immunocompromised. Six patients required multidrug antibiotic treatment for a median duration of 5.5 months (range 3-17 mos). The median follow-up duration was 8.5 months (range 2 wks-29 mos).

CONCLUSION

Although the incidence of cutaneous NTM is rare, the diagnosis should be considered in patients presenting with chronic wounds. Most patients require treatment with multidrug antibiotic therapy, although uncomplicated abscesses can be treated with surgical incision and drainage alone.

Two Episodes of Cutaneous Non-Tuberculous Mycobacterial Infection in a Patient with Psoriasis

Non-tuberculous mycobacteria (NTM) are a group of environmental pathogens, which cause a broad spectrum of disease. The incidence of NTM infection is increasing, especially in immunocompromized patients. The past three decades also saw a rapid increase in the incidence of NTM infection involving otherwise healthy subjects. We report a case of cutaneous NTM infection in a 79-year-old Chinese woman, who was receiving methotrexate for psoriasis. Mycobacterial culture grew Mycobacterium abscessus, and the lesions cleared with a combination of oral clarithromycin, ciprofloxacin and doxycycline. Interestingly, she then developed a second episode of cutaneous NTM infection with Mycobacterium haemophilum over the same body region, five years after stoppage of methotrexate. Both episodes were separated in time and involved different species, indicating that they were independent from each other. We further discuss the risk factors for cutaneous NTM infection, treatment, and highlight the need for diagnostic vigilance.

Twenty-eight cases of Mycobacterium marinum infection: retrospective case series and literature review

PURPOSE

Invasive Mycobacterium marinum disease (tenosynovitis and osteomyelitis) may be an increasingly common manifestation of M. marinum infection that presents unique diagnostic and therapeutic challenges. We conducted a retrospective case series and literature review of M. marinum infection to better understand the clinical spectrum of invasive versus cutaneous disease.

METHODS

We reviewed electronic medical records for all M. marinum infections at Duke University Medical Center from January 1, 1996 to April 30, 2014. Published case series of M. marinum infection since 1990 reporting >5 cases were systematically ascertained and reviewed.

RESULTS

Twenty-eight cases of M. marinum infection were identified from our institution. Twenty cases (87 %) involved aquatic exposure, and 26 (93 %) involved finger and/or hand lesions. Median time to diagnosis was 3.5 months. Nineteen (68 %) cases had invasive infection, and 9 (32 %) were cutaneous; invasive infection was more common with older age. Granulomatous inflammation and acid-fast bacilli were noted on pathologic examination in 11 (58 %) and 3 (16 %) cases, respectively. Primarily monotherapy was used in 2 (12 %) cases, dual therapy in 8 (47 %) cases, and three-drug therapy in 7 (41 %) cases; three-drug therapy was more common with invasive infection. Median duration of treatment was 5 months. Adjunctive surgery was performed for 18 (95 %) cases of invasive infection and 4 (44 %) of cutaneous infection. Twenty-one (75 %) cases improved, while 7 (25 %) were lost to follow-up.

CONCLUSIONS

Distinguishing between invasive and cutaneous M. marinum infection may have important consequences in terms of antibiotic choice and need for adjunctive surgery.

Mycobacterium marinum infection: a case report

The infection by Mycobacterium marinum in humans is relatively uncommon. When it occurs, it mainly affects the skin, usually with a chronic, indolent and benign evolution. The diagnosis requires a high index of suspicion, and a significant delay may be observed between the first symptoms to the final diagnosis. This present case reports a M. marinum infection in an immunocompetent patient that had a chronic undiagnosed injury on the dominant hand for at least five years. The patient had several medical consultations, without proper suspicion, hampering adequate diagnostic investigation. Histopathology detected tuberculoid granulomas, but showed no acid-fast bacilli. The culture in appropriate medium and the polymerase chain reaction-restriction enzyme analysis (PRA)-hsp65 confirmed the diagnosis. Treatment with clarithromycin (1 g/day) for three months was effective. Although uncommon, this infection is a contact zoonosis. Therefore, it is important for clinicians to be aware of this diagnosis and properly guide preventable measures to professionals that are in risk group.