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

A multivariable model of clinical features for distinguishing sporotrichosis and Mycobacterium marinum cutaneous infection

To investigate differences in the clinical features of patients with sporotrichosis and cutaneous Mycobacterium marinum infection, and develop a prediction model for the initial identification. A total of 121 patients were selected based on the results from etiological culture. Logistic regression analyses were employed to identify the most valuable variables. In the multivariate logistic regression analysis, the following were finally considered independent predictors (OR = 3.650∼14.024, P<0.05) of cutaneous M. marinum infection: age<60 years (P = 0.031); female (P = 0.001); only the extremities involved (P = 0.031); clear triggers (P = 0.022); and presence of swelling (P = 0.024). A nomogram was developed based on these factors, and the area under the curve was 0.860. The model presented is based on clinical features and can help identify patients with sporotrichosis and cutaneous M. marinum infection. This may help increase the accuracy of doctors' initial examination and diagnostic outcomes.

Seventeen cases of Mycobacterium marinum infection in Italy: A multicenter retrospective study

Mycobacterium marinum infection is rare, misrecognized and underdiagnosed but can cause severe clinical pictures, especially if the diagnosis is late and the patient is immunocompromised. Treatment includes long-term antibiotic therapy combined with surgical therapy when necessary. We performed a multicenter retrospective study with data from five Italian hospitals describing the epidemiological, clinical, bacteriological characteristics, and treatment outcome of subjects diagnosed with M. marinum infection. During the study period 17 subjects were enrolled. The median time from symptoms onset to diagnosis was 124 days. Thirteen out of 17 were bacteriologically confirmed cases. In all cases, expect one, at least two antibiotics were used with a median of 6 months of treatment, leading to clinical resolution. Too often, the diagnosis of M. marinum infection is delayed and it remains largely presumptive. Prospective studies and randomized controlled trials are necessary to better understand the most appropriate therapeutic regimen and duration.

Mycobacterium heraklionense: An emerging cause of hand tenosynovitis

Misdiagnosis of Mycobacterium heraklionense tenosynovitis is common due to the challenging identification and perceived rarity of the disease. This can result in delayed therapy initiation and potentially irreversible consequences. In this report, we present an additional case of hand tenosynovitis, which highlights the diagnostic and management challenges of Mycobacterium heraklionense tenosynovitis and provides further evidence of its emergence as a cause of tenosynovitis. Additionally, we provide a comprehensive summary of published case reports that describe Mycobacterium heraklionense tenosynovitis.

Cutaneous infection due to Mycobacterium marinum: A series of four cases from Kerala, India

Mycobacterium marinum is a non-tuberculous mycobacterium which can be found in naturally occurring, non-chlorinated water sources and is a known pathogen that affects fish. In humans, M. marinum typically results in cutaneous lesions, it can occasionally lead to more invasive disorders. We discuss four cases of M. marinum-related cutaneous infections examined in a tertiary care facility. We want to draw attention to the challenges of accurately diagnosing this infection, stress the significance of having a high level of clinical suspicion in order to identify it, and discuss the available treatment choices.

Semisynthesis, Structure Elucidation and Anti-Mycobacterium marinum Activity of a Series of Marine-Derived 14-Membered Resorcylic Acid Lactones with Interesting Ketal Groups

The incidence of Mycobacterium marinum infection is on the rise; however, the existing drug treatment cycle is lengthy and often requires multi-drug combination. Therefore, there is a need to develop new and effective anti-M. marinum drugs. Cochliomycin A, a 14-membered resorcylic acid lactone with an acetonide group at C-5' and C-6', exhibits a wide range of antimicrobial, antimalarial, and antifouling activities. To further explore the effect of this structural change at C-5' and C-6' on this compound's activity, we synthesized a series of compounds with a structure similar to that of cochliomycin A, bearing ketal groups at C-5' and C-6'. The R/S configuration of the diastereoisomer at C-13' was further determined through an NOE correlation analysis of CH3 or CH2 at the derivative C-13' position and the H-5' and H-6' by means of a 1D NOE experiment. Further comparative 1H NMR analysis of diastereoisomers showed the difference in the chemical shift (δ) value of the diastereoisomers. The synthetic compounds were screened for their anti-microbial activities in vitro. Compounds 15-24 and 28-35 demonstrated promising activity against M. marinum, with MIC90 values ranging from 70 to 90 μM, closely approaching the MIC90 of isoniazid. The preliminary structure-activity relationships showed that the ketal groups with aromatic rings at C-5' and C-6' could enhance the inhibition of M. marinum. Further study demonstrated that compounds 23, 24, 29, and 30 had significant inhibitory effects on M. marinum and addictive effects with isoniazid and rifampicin. Its effective properties make it an important clue for future drug development toward combatting M. marinum resistance.

Mycobacterium marinum cutanous infection misdiagnosed as sporotrichosis in a patient with systemic lupus erythematosus: A case report

Mycobacterium marinum(M. marinum ), a slow-growing bacterium in freshwater and seawater, can cause cutanous and extracutaneous infections. A fisher-woman with systemic lupus erythematosus (SLE) presented with chronic polymorphic rashes in a lymphangitic pattern was initially misdiagnosed as sporotrichosis. The final diagnosis of M. marinum and Candida dubliniensis co-infection was confirmed based on the skin histopathology, pustule culture, MetaCAP sequencing and effective antibiotic combination treatments.

A Rapid PCR-Based Diagnostic Method for Skin Infection with Mycobacterium marinum

Objective

The increasing incidence of chronic skin infections caused by Mycobacterium marinum, coupled with the time-consuming and low detection rates nature of traditional culture and histological-based diagnostic methods, underscores the need for an expedited approach. The study aims to develop a rapid and efficient method for detecting M. marinum with PCR technology.

Methods

We designed four pairs of primers based on DNA sequences from GeneBank and prior studies, we utilized both PCR and Real-time PCR to identify M. marinum. Specificity and sensitivity assessments were conducted in vitro by DNAs extracted from M. marinum and other bacterial or fungal cultures. Further validation was performed through the implementation of a mouse skin infection model to optimize and confirm the efficacy of the detection method in both fresh and paraffin-embedded skin tissues. The same PCR testing system was further confirmed with paraffin-embedded skin tissues samples from patients as well.

Results

The results of the study indicate promising outcomes for the four-pair primers system. It demonstrated 100% sensitivity in detecting M. marinum from purified cultures, including typical strains and nine clinical isolates, while achieving a specificity of 100%. This specificity was evidenced by the absence of PCR products from 12 bacterial species, 12 fungi species, and six other non-tuberculous mycobacterium (NTM) species. In the animal model, the PCR assay exhibited high detection efficacy for both infected fresh tissues and paraffin-embedded tissues, with a slight superiority observed in fresh tissues. However, the PCR assay exhibited high detection efficacy for clinical paraffin-embedded tissues. These findings collectively underscore the robust detection capabilities of our four-pair primers in both in vitro and in vivo settings.

Conclusion

A sensitive and highly specific rapid detection system has been successfully developed that can be used to detect M. marinum in both infected fresh tissues and paraffin-embedded tissues.

ALA-PDT shortens the course of antibiotic therapy for skin infection caused by Mycobacterium marinum

BACKGROUND

Recently, the number of cases of Mycobacterium marinum infection has increased. Due to the nonspecific clinical manifestations and lack of standardized treatment guidelines, these infections are often misdiagnosed and are challenging to treat.

METHODS

In this study, four patients had M. marinum skin infections accompanied by a high-risk exposure history and were diagnosed by bacterial culture and gene chip. Two patients were treated with antibiotic therapy alone, and the other two patients were treated with 5-aminolevulinic acid photodynamic therapy (ALA-PDT) combined with antibiotics.

RESULTS

All four patients enrolled in the study were cured with 100 % efficacy. Two patients were cured after receiving two active antibiotics for 4 months. The other two patients, having considered the drug resistance and intolerance described above, were cured after receiving two active antibiotics for 1-1.5 months along with combination therapy with ALA-PDT.

CONCLUSION

Combination therapy with ALA-PDT and antibiotics was chosen to shorten the duration of antibiotic treatment and reduce the occurrence of adverse reactions.

Treatment of non-tuberculosis mycobacteria skin infections

Non-tuberculosis mycobacteria (NTM) skin infections have become increasingly prevalent in recent years, presenting a unique challenge in clinical management. This review explored the complexities of NTM infections localized to the superficial tissues and provided valuable insights into the optimal therapeutic strategies. The antibiotic selection should base on NTM species and their susceptibility profiles. It is recommended to adopt a comprehensive approach that considers the unique characteristics of superficial tissues to improve treatment effectiveness and reduce the incidence of adverse reactions, infection recurrence, and treatment failure. Infection control measures, patient education, and close monitoring should complement the treatment strategies to achieve favorable outcomes in managing NTM skin infections. Further efforts are warranted to elucidate factors and mechanisms contributing to treatment resistance and relapse. Future research should focus on exploring novel treatment options, innovative drug development/delivery platforms, and precise methodologies for determining therapeutic duration. Longitudinal studies are also needed to assess the long-term safety profiles of the integrated approaches.

A Series of 35 Cutaneous Infections Caused by Mycobacterium marinum in Han Chinese Population

Cutaneous Mycobacterium marinum infection is an increasingly infectious disease presenting unique diagnostic and therapeutic challenges. The aim of this study was to evaluate the differences in time to treatment among patients with different types of skin lesions and who were treated with single or multidrug therapies. In addition, the clinical characteristics of M. marinum infection were explored and the mechanism of the host immune responses was investigated. The electronic medical records of 35 patients with M. marinum infection were reviewed. The clinical characteristics, histopathological and laboratory data, and treatment outcomes were analyzed. Immunohistochemical analysis was performed to clarify the immune mechanisms induced by M. marinum infection in 9 patients and 5 healthy controls. Of the 35 patients, 25 (71.4%) had lesions with sporotrichoid patterns. The duration of patients with sporotrichoid lesions or treatment with multiple drugs was longer, although differences were not significant, possibly due to the small cohort. However, this trend was also observed in previous studies, making it worthy of further attention. Expression levels of cytokines (IFN-γ, IL-4, IL-9, and FOXP3) were significantly upregulated in the patient specimens, whereas there were no significant differences in IL-17 and IL-22 expression levels between the patient and control groups.

Mycobacterium marinum: A Case-Based Narrative Review of Diagnosis and Management

Skin and soft tissue infections caused by non-tuberculous mycobacteria are occurring more frequently in recent years. However, chronic skin and soft tissue lesions present a challenge for clinicians, as the diagnostic work-up and definitive diagnosis require knowledge and available laboratory resources. We present here the case of a 66-year-old male patient who presented with painful abscess-like nodules on his right hand and forearm, which worsened after treatment with an anti-TNF-a agent. The fluid specimen taken from the lesion was positive for mycobacteria according to the acid-fast stain. Mycobacterium marinum was identified, first by next-generation sequencing and finally grown on culture, after eight weeks. Acknowledging the complexity of diagnosing and managing infections by non-tuberculous mycobacteria, and especially Mycobacterium marinum, we provide a review of the current epidemiology, clinical characteristics, diagnosis and management of Mycobacterium marinum infection.

Current treatment options for Mycobacterium marinum cutaneous infections

INTRODUCTION

Mycobacterium marinum is a slowly growing photochromogenic nontuberculous mycobacterium that has special growth characteristics. It causes a uniquely human disease, a cutaneous syndrome named fish tank granuloma or swimming pool granuloma because of the strong epidemiological links with water. The treatment of this disease involves the use of different antimicrobials alone and in combination, depending on the severity of the disease. The antibiotics most frequently used are macrolides, tetracyclines, cotrimoxazole, quinolones, aminoglycosides, rifamycins, and ethambutol. Other approaches include the use of surgery in some cases. New treatment options, like new antibiotics, phage therapy, phototherapy, and others are currently being developed with good in vitro experimental results. In any case, the disease is usually a mild one, and the outcome is good in most of the treated patients.

AREAS COVERED

We have searched the literature for treatment schemes and drugs used for treatment of M. marinum disease, as well as other therapeutic options.

EXPERT OPINION

Medical treatment is the most recommended approach option, as M. marinum is usually susceptible to tetracyclines, quinolones, macrolides, cotrimoxazole, and some tuberculostatic drugs, usually used in a combined therapeutic scheme. Surgical treatment is an option that can be curative and diagnostic in small lesions.

Mycobacterium marinum: A Challenging Cause of Protracted Tenosynovitis

Mycobacterium marinum infections are rare, and they can be difficult to diagnose and treat. This may lead to further spread of the infection and complications, such as tenosynovitis, pyomyositis, and osteomyelitis. A 40-year-old previously healthy man presented with tenosynovitis of the extensor tendons on the second phalanx of his right hand. He was initially treated with steroid injections without any effect. Followingly, ulceration and an abscess developed on the dorsal site of the hand. At this point, it came to the physician's knowledge that the patient had been cleaning an aquarium before onset of symptoms. After progression to massive tenosynovitis, the patient was admitted and underwent multiple surgical debridements. Briefly, after the first surgery, an interferon-γ release assay was positive, and treatment for M. marinum with rifampicin and azithromycin was initiated after eight months of symptoms. Later, a surgical biopsy showed acid-fast bacilli, and a polymerase chain reaction confirmed the diagnosis of M. marinum. In this case story, we highlight the difficulties of diagnosing and managing this complicated infection, describe the considerable morbidity associated with it, and suggest that local tissue concentrations could be useful to improve clinical outcomes, as these concentrations are potentially suboptimal.

Comparative Evaluation of LAMP and Nested PCR for the Rapid Diagnosis of Mycobacterium marinum Infection

Purpose

Culture of Mycobacterium marinum is very time-consuming, taking several weeks to produce positive results. Seeking rapid and sensitive diagnostic methods for diagnosis can greatly improve patient treatment. Our study aimed to compare the rapid diagnostic abilities of polymerase chain reaction (PCR), nested PCR and loop mediated isothermal amplification (LAMP) of detecting M. marinum in skin samples from patients with M. marinum infection.

Methods

A total of 6 M. marinum strains and 6 skin samples with definite diagnosis of M. marinum infection were included in the study. We optimized LAMP performance for detection of M. marinum genomic DNA and confirmed the specificity of the primers. Then, the sensitivity of the LAMP and nested PCR assays were assessed by M. marinum strains and clinical samples.

Results

Nested PCR was 10-fold more sensitive than the LAMP assay by serial dilution of M. marinum DNA. PCR positive samples were all positive by LAMP detection of 6 clinical M. marinum strains. Out of 6 clinical skin specimens confirmed as M. marinum infection, 0 (0%), 3 (50%), 3 (50%), and 4 (66.6%) were positive by PCR, nested PCR, LAMP and culture. The LAMP shared the same sensitivity than nested PCR in M. marinum strains and clinical samples, but it was easy to perform and faster than nested PCR assay.

Conclusion

Compared with conventional PCR, LAMP and nested PCR are more sensitive and have a higher detection rate of M. marinum in clinical skin specimens. The LAMP assay proved to be more suitable for rapid diagnosis of M. marinum infection in a shorter time, especially in resource-limited settings.

Unusual Mycobacterium marinum Infection in a Heart Transplant Recipient: A Case Report

Mycobacterium marinum (M. marinum) is a species of nontuberculous mycobacteria that is a rare cause of disease in humans and is usually associated with aquatic exposures. Symptoms manifest, on average, three weeks after exposure, although cases with longer incubation periods have been reported in the literature. Herein, we describe an unusual case presentation of an M. marinum infection in the left upper extremity of a heart transplant recipient. The case is notable for its prolonged incubation period and for being the first documented case of M. marinum infection in a heart transplant recipient. We hypothesize that, given the patient's immunosuppressive medication regimen in the post-transplant period, this case could represent a reactivation phenomenon of a latent infection.

Mycobacterium marinum: A brief update for clinical purposes

Mycobacterium marinum (M. marinum) is a free-living, slow grower nontuberculous mycobacteria (NTM), strictly related to Mycobacterium tuberculosis, that causes disease in fresh and saltwater fish and it is one of the causes of extra-pulmonary mycobacterial infections, ranging in human from simple cutaneous lesions to disseminated forms in immunocompromised hosts. The first human cases of M. marinum infection were reported from skin lesions of swimmers in a contaminated pool, in 1951, in Sweden by Norden and Linell. Two conditions are required to develop M. marinum infection: (1) skin solution of continuity and (2) exposure to the contaminated water or direct contact with fish or shellfish. The so-called "fish-tank granuloma", the most frequent cutaneous manifestation of M. marinum infection, is characterized by a single papulonodular, verrucose and/or ulcerated granulomatous lesion in the inoculum site. Careful patient's history collection, high clinical suspicion and appropriate sample (e.g. cutaneous biopsy) for microbiological culture are crucial for a timely diagnosis. The treatment is not standardized yet and relies on administration of two active antimycobacterial agents, always guided by antimicrobial susceptibility test on culture, with macrolides and rifampin as pivotal drugs, as well as prompt surgery when feasible. In this narrative review, we provide to Clinicians an updated report of epidemiology, microbiological characteristics, clinical presentation, diagnosis, and management of M. marinum infection.

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.

Mycobacterium marinum cellulitis: A fishy etiology

Skin and soft tissue infections account for 2% of emergency department visits annually, though more unusual causative bacteria associated with saltwater exposure may result in morbidity. Mycobacterium marinum represents a rare but important cause of cellulitis, which if untreated or improperly managed, can progress to dactylitis or osteomyelitis. This unusual diagnosis is made more challenging due to the prolonged incubation period of approximately 21 days, temporally separating the inoculation from the disease. Patients will present with a nodular rash in a sporotrichoid pattern. While doxycycline is one antibiotic providing saltwater coverage, M. marinum has variable sensitivities to anti-mycobacterial antibiotics, and thus biopsy helps confirm the diagnosis as well as provide sensitivities for treatment. Emergency clinicians should inquire about environmental risk factors when caring for patients with cellulitis, especially with atypical skin presentations, and consider M. marinum as a rare but important cellulitis etiology.

Beyond the approved: target sites and inhibitors of bacterial RNA polymerase from bacteria and fungi

Covering: 2016 to 2022RNA polymerase (RNAP) is the central enzyme in bacterial gene expression representing an attractive and validated target for antibiotics. Two well-known and clinically approved classes of natural product RNAP inhibitors are the rifamycins and the fidaxomycins. Rifampicin (Rif), a semi-synthetic derivative of rifamycin, plays a crucial role as a first line antibiotic in the treatment of tuberculosis and a broad range of bacterial infections. However, more and more pathogens such as Mycobacterium tuberculosis develop resistance, not only against Rif and other RNAP inhibitors. To overcome this problem, novel RNAP inhibitors exhibiting different target sites are urgently needed. This review includes recent developments published between 2016 and today. Particular focus is placed on novel findings concerning already known bacterial RNAP inhibitors, the characterization and development of new compounds isolated from bacteria and fungi, and providing brief insights into promising new synthetic compounds.

Treatment and Outcome of Culture-Confirmed Mycobacterium marinum Disease

Background

Mycobacterium marinum is a nontuberculous mycobacterium that causes skin and soft tissue infections. Treatment consists of multiple antibiotics, sometimes combined with surgical debridement. There is little evidence for the choice of antibiotics, the duration of treatment, and the role of susceptibility testing.

Methods

We performed a retrospective cohort study of culture-confirmed M. marinum infections in the Netherlands in the 2011–2018 period. Clinical characteristics, in vitro susceptibility, extent of disease, treatment regimens, and outcomes were analyzed. Incidence was assessed from laboratory databases.

Results

Forty cases of M. marinum infection could be studied. Antibiotic treatment cured 36/40 patients (90%) after a mean treatment duration of 25 weeks. Failure/relapse occurred in 3 patients, and 1 patient was lost to follow-up. Antibiotic treatment consisted of monotherapy in 35% and 2-drug therapy in 63%. Final treatment contained mostly ethambutol–macrolide combinations (35%). Eleven patients (28%) received additional surgery. We recorded high rates of in vitro resistance to tetracyclines (36% of isolates). Tetracycline resistance seemed correlated with poor response to tetracycline monotherapy. The annual incidence rate was 0.15/100000/year during the study period.

Conclusions

Prolonged and susceptibility-guided treatment results in a 90% cure rate in M. marinum disease. Two-drug regimens of ethambutol and a macrolide are effective for moderately severe infections. Tetracycline monotherapy in limited disease should be used vigilantly, preferably with proven in vitro susceptibility.

Increasing Recognition of Community-Acquired, Non-Tuberculous Mycobacterial Infections of the Hand and Wrist

Background

In this study, we present our experience with community-acquired, culture-positive, non-tuberculous mycobacterial (NTM) infections of the hand and wrist and compare the clinical features, risk factors, diagnostic delays, and treatment outcomes among patients referred for surgical consultation at our institution over a five-year period.

Methodology

We retrospectively identified patients on chart review who were diagnosed with culture-positive, extrapulmonary, cutaneous NTM infections between January 1, 2014, and December 31, 2018. Only patients with community-acquired NTM infections of the hand and wrist were included. Patient demographics, risk factors, location, diagnostic delays, NTM species isolated, treatment modalities, and treatment outcomes were collected and analyzed. These variables were further compared between patients who participated in fishing-related activities and those who did not.

Results

A total of 10 patients were identified with community-acquired NTM infections of the hand or wrist. Of these patients, eight (80%) were male, and six (60%) had participated in fishing-related activities prior to the initial presentation. The majority of patients had Mycobacterium marinum isolates (n = 6, 60%) and involved the hand (n = 8, 80%). M. marinum isolates were associated with a significantly shorter time to diagnosis (p = 0.02). All patients underwent surgical management with a prolonged course of postoperative antibiotics and were cured of their infection at the end of their treatment course.

Conclusions

Proper risk factor documentation and heightened clinical awareness are essential to reduce delays in the diagnosis of NTM skin and soft tissue infections and provide the best chance for curative therapy.

A Case of Hypercalcemia in an Immunocompetent Patient with Disseminated Mycobacterium marinum Infection with a Rain Barrel as the Most Likely Primary Source

Infection with Mycobacterium marinum is common in fish, and so human infection usually arises from contact with contaminated water or fish. A solitary papulonodular lesion on a finger or hand is the typical presentation. Disseminated infections are rare and mostly seen in immunocompromised patients.

We present a rare case of disseminated M. marinum infection presenting with polyarthritis, tenosynovitis, dactylitis, and (sub)cutaneous and intramuscular lesions in an immunocompetent patient. This case was complicated by hypercalcemia, renal failure and eventually death. A contaminated rain barrel was most likely the primary source of the infection.

Fish Tank Granuloma Presenting as a Nasal Cavity Mass

Mycobacterium marinum is a free-living nontuberculous mycobacterium that is widely distributed in freshwater and seawater around the world. Granulomatous skin infection from M. marinum in people who are exposed to fish or aquatic environments is a rare condition known as fish tank granuloma. The granuloma mainly occurs on the skin of the upper limb, in a few cases on the face, and rarely in the nasal cavity. We describe a case of M. marinum infection that presented as a nasal cavity mass. A 57-year-old woman who was receiving infliximab for psoriatic arthritis visited our hospital with a complaint of right nasal obstruction. A granulomatous mass with an irregular surface was found in the anterior part of the right nasal cavity. Tissue biopsy revealed granulation tissue. Since the application of steroid ointment did not reduce the size of the mass, the tumor was resected under local anesthesia, and the base was cauterized. The pathological finding was an inflammatory granuloma with negative Ziehl-Neelsen staining. The granuloma recurred 3 months after resection. The interferon-gamma release assay (IGRA) test was positive, and therefore, a mycobacterial tissue culture test was performed because of suspected nasal tuberculosis, which identified M. marinum. The nasal cavity mass disappeared 2 months after the administration of minocycline, followed by clarithromycin, and subsequent discontinuation of infliximab. M. marinum infection can cause an intranasal mass. IGRA and the mycobacterial tissue culture test are useful for diagnosis. As in this case, the nasal lesion may be excised as an inflammatory nasal granuloma, and therefore, there may be many more "hidden" cases of M. marinum infection. If nasal granulation is present, the possibility of M. marinum infection should be considered.

Mycobacterium marinum: nodular hand lesions after a fishing expedition

Mycobacterium marinum is a slow-growing, acid-fast bacillus in the category of non-tuberculous mycobacteria which most commonly cause skin and soft tissue infections in patients, particularly those with aquatic exposure. Classically, M. marinum skin and soft tissue infections clinically manifest with formation of nodular or sporotrichoid extremity lesions, or deeper space infections such as tenosynovitis and osteomyelitis. Disseminated disease may occur in immunocompromised hosts. M. marinum is a slow-growing organism that is challenging to culture, as it typically requires 5-14 days (yet may take up to several weeks) with low temperatures of approximately 30°C to yield growth. In terms of treatment, further data are needed to elucidate the optimal regimen and duration for M. marinum infections. Combination therapy with clarithromycin and ethambutol is recommended for treatment of skin and soft tissue infections, with addition of rifampicin for deeper space infections. Surgery may be needed in addition to medical management.

Mycobacterium marinum infection simulating chromomycosis: a case report

Skins infections caused by Mycobacterium marinum occur only rarely. We report one case of chronic and extensive M. marinum cutaneous infection simulating chromoblastomycosis and review the pertinent literature. A 52-year-old farmer reported a 32-year chronic skin problem on his right lower limb, resulting from contact with cacti. It consisted of skin lesion presenting with dyschromic atrophic center plate and verrucous borders with hematic crusts, extending from the knee anteriorly to the inferior third of the right leg. Mycobacterium marinum infection was detected by histopathological examination of a skin fragment, culture for mycobacteria and genetic mapping of the culture material. The patient was successfully treated with Ethambutol, Rifampicin and Trimethoprim-Sulfamethoxazole. The clinical and histopathological findings of M. marinum infection is nonspecific showing clinical polymorphism and bacilli are rarely evident on histopathological examination. Given these difficulties, it is essential to perform tissue culture in a suspicious case and it is important keep this infection in mind in patients with long-lasting indolent verrucous lesions and a history of exposure to sea water, freshwater, aquaria or fish.

Modeling Tubercular ESX-1 Secretion Using Mycobacterium marinum

Pathogenic mycobacteria cause chronic and acute diseases ranging from human tuberculosis (TB) to nontubercular infections. Mycobacterium tuberculosis causes both acute and chronic human tuberculosis. Environmentally acquired nontubercular mycobacteria (NTM) cause chronic disease in humans and animals. Not surprisingly, NTM and M. tuberculosis often use shared molecular mechanisms to survive within the host. The ESX-1 system is a specialized secretion system that is essential for virulence and is functionally conserved between M. tuberculosis and Mycobacterium marinum .

Dactylitis: A pictorial review of key symptoms

Dactylitis refers to a global swelling of a finger or a toe giving it a clinical sausage-shape presentation. It is an extremely suggestive symptom as it guides the rheumatologist towards a shortlist of diagnoses. However, radiologists are less familiar with dactylitis. The aim of this review is to detail and illustrate the main causes of dactylitis using standard X-ray imaging, ultrasound, computed tomography and magnetic resonance imaging in order to make radiologists more familiar with this symptom by illustrating the various conditions that are associated with dactylitis including infection, peripheral spondyloarthritis, sarcoidosis, microcrystalline deposition, osteoid osteoma, and sickle cell disease.

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.

Deep infection with Mycobacterium marinum: successful treatment of a frequently misdiagnosed disease

We report a rare yet typical presentation of a severe infection with Mycobacterium marinum that affected the deep structure of the hand and wrist of a 43-old fish breeder. A combination therapy of surgical debridement and antibiotic treatment with clarithromycin and ethambutol for 6 months led to a total resolution of the symptoms. Intensive rehabilitation completely restored the function of the hand.

Preliminary evaluation of the positively and negatively charge effects of tetra-substituted porphyrins on photoinactivation of rapidly growing mycobacteria

This manuscript reports, at the first time, the photoinactivation evaluation of tetra-cationic and anionic porphyrins as photosensitizers (PS) for the photodynamic inactivation (PDI) of rapidly growing mycobacteria strains. Two different charged porphyrin groups were obtained commercially. PDI experiments in the strains Mycobacterium massiliense e Mycobacterium fortuitum conducted with adequate concentration (without aggregation) of photosensitizer under white light at a fluence rate of 50 mW/cm² over 90 min showed that the most effective PS caused a 100 times reduction in the concentration of viable mycobacteria. The present results show that porphyrin with positively charge are more efficient PS than anionic porphyrin (negatively charged) against M. massiliense e M. fortuitum. It is also clear that the effectiveness of the molecule as PS for PDI studies with mycobacteria is strongly related with the porphyrin peripheral charge, and consequently their solubility in physiological media. Cationic PSs might be promising anti-mycobacteria PDI agents with potential applications in medical clinical cases and bioremediation.