Acid-fast bacteria as causative agents of skin and soft tissue infections: case presentations and literature review

ABSTRACT Acid-fast bacteria can be implicated in skin and soft tissue infections. Diagnostic identification can be challenging or not feasible by routine laboratory techniques, especially if there is no access to the Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) technology. Here, we present two cases of skin and soft tissue infections caused by two different acid-fast bacteria, Nocardia brasiliensis and Mycobacterium marinum. They both grew on Löwenstein-Jensen medium, Sabouraud agar medium and blood agar medium. Both bacteria appeared acid-fast by Ziehl-Neelsen stain and Gram-positive by Gram stain. The identification was performed by MALDI-TOF MS and gene analysis. N. brasiliensis and nontuberculous mycobacterium M. marinum represent rare pathogens that cause severe skin and soft tissue infections. Failure to identify the causative agent and subsequent inappropriate or inadequate treatment may lead to severe complications or even disseminated disease, especially in immunocompromised individuals.

Epidemiological characteristics of Mycobacterium marinum infection cases in a hospital in Shandong province, 2019 to 2021 / 中华皮肤科杂志

Objective:To investigate epidemiological characteristics of Mycobacterium marinum infection cases in the Dermatology Hospital of Shandong First Medical University from January 2019 to December 2021. Methods:Data were collected from patients with Mycobacterium marinum infection in the Dermatology Hospital of Shandong First Medical University from January 2019 to December 2021. Demographic characteristics, clinical features and prognosis of patients were retrospectively analyzed. Differences between groups were analyzed using t test, Chi-square test and Fisher′s exact test; factors influencing the time to diagnosis (the time from the first appearance of skin manifestations to the diagnosis of Mycobacterium marinum infection in the hospital) longer than 12 months were analyzed using Chi-square test and multivariate logistic regression model, and the odds ratio ( OR) and 95% confidence interval (95% CI) were calculated. Results:From 2019 to 2021, a total of 373 cases of Mycobacterium marinum infection were diagnosed in the hospital, and the number of cases in 2021 was 4.06 times that in 2019; the male-to-female ratio was 1∶1.49, and their age was 54.24 ± 14.04 years. Among the 373 patients, 211 (56.57%) had a history of trauma caused by aquatic products (e.g., fishes, shrimps), of which 51 (24.17%) were stung by sea perch. Skin lesions involved unilateral limbs in 327 (87.67%) patients, only involved the hands or wrists in 188 (50.40%) patients, and 258 (69.17%) had multiple skin lesions. Among the 341 patients with treatment information, 105 (30.79%) were given one antibiotic, 214 (62.76%) received combination treatment with two antibiotics, and 15 (4.40%) were treated with three antibiotics. The response rate was 98.77% (321/325), and the time to diagnosis [ M ( Q1, Q3) ] was 5.03 (3.00, 8.37) months. Multivariate logistic regression analysis indicated higher proportions of males ( OR [95% CI]: 1.95[1.11 - 3.41], P = 0.02), patients aged > 55 years ( OR [95% CI]: 1.82[1.04 - 3.18], P = 0.04), patients with skin lesions only involving hands, arms or lower limbs ( OR [95% CI]: 3.48[1.83 - 6.61], P<0.001) among the patients whose time to diagnosis was longer than 12 months. Conclusions:The number of patients with Mycobacterium marinum infection was increased in the Dermatology Hospital of Shandong First Medical University year by year from 2019 to 2021, and fish sting wounds were the main cause of infection. The most common treatment regimen was the combination of two antibiotics, with a high efficacy profile.

Diagnosis of Mycobacterium marinum infection based on photochromogenicity: a case report

ABSTRACT A 35-year-old immunocompetent woman from southern China went to the hand surgery clinic with a six-month history of progressive swelling in her right index finger. She had been pinched by a lobster and had received several treatments without any improvement. Pus specimens were taken from the swollen parts of her finger, and the pathology showed granulomatous inflammation. Ziehl-Neelsen staining revealed positive bacillus in the pus specimens. The bacteria grew well on Columbia blood agar. However, the MALDI-TOF MS and 16S rRNA gene sequencing were not able to distinguish between Mycobacterium marinum and Mycobacterium ulcerans because of their close genetic relationship. Photochromogenicity testing can help differentiate between these species based on the alteration in colony color after light exposure. For our patient, the colonies turned yellow after 18h of incubation in the sun, identifying the species as M. marinum. Besides surgical drainage, the patient received rifampicin and clarithromycin for three months, and her symptoms resolved without relapse after six months of follow-up.

Clinicopathological analysis of 56 cases of swimming pool granuloma / 中华皮肤科杂志

Objective:To investigate clinicopathological features of swimming pool granuloma.Methods:From January 2018 to January 2021, 56 patients with swimming pool granuloma were collected from Tianjin Academy of Traditional Chinese Medicine Affiliated Hospital, and their clinical and pathological characteristics were retrospectively analyzed.Results:Among the 56 patients, 16 were males and 40 were females, with an average age of 60.84 years. The most common exposure type among these patients was handling of infected fishes or seafood by aquaculture workers and residents in daily cooking (31/56) , the average incubation period was 4.58 weeks, and the average time to diagnosis was 3.19 months. All skin lesions were located at the upper extremities, mainly manifesting as erythema and papular nodules, and sometimes as pustules, ulcers, granulomas or verrucous plaques. Eleven patients presented with solitary skin lesions, 36 with sporotrichoid skin lesions, and 6 with bilateral sporotrichoid lesions. Histopathologically, infectious granulomas were observed in all patients except 4 without specific changes, and 37 presented with characteristic exudative necrosis, with varying amounts of fibrinoid exudative or necrotic elements in the center, and a large number of neutrophils, histiocytes and multinucleated giant cells infiltrating inside or around it. Sequences of Mycobacterium marinum were identified in all 56 cases by metagenomic DNA sequencing of pathogenic microorganisms. Conclusion:In Tianjin area, swimming pool granuloma mostly affected elderly females, handling of infected fishes or seafood was the main type of exposure, and skin lesions were histopathologically characterized by exudative necrotic granulomas.

Application of Mycobacterium marinum infected zebrafish for evaluation of anti-tuberculosis drugs / 药学学报

Tuberculosis (TB) is a serious infectious disease caused by Mycobacterium. tuberculosis. In recent years, with the emergence of drug-resistant forms, the development of new anti-tuberculosis drugs is urgently needed. In this study, we used Mycobacterium marinum (M. marinum), which is highly similar to M. tuberculosis, to establish a M. marinum infected-zebrafish model and quantitative PCR (qPCR) method for bacterial count analysis. The results showed that injecting M. marinum into the yolk sac is an efficient and convenient way to infect zebrafish embryos. By counting the survival rate of infected zebrafish and the number of bacteria in zebrafish by Ziehl-Neelsen staining, we analyzed the efficacy of isoniazid and rifampicin as anti-tuberculosis drugs and the synergistic effect of drugs. The results suggested that three evaluation methods exhibit good consistency. This study demonstrated that zebrafish-M. marinum infection model combined with qPCR analysis is a simple and efficient method for in vivo screening and evaluation of anti-tuberculosis drugs. Animal experiments were carried out in accordance with the provisions for animal ethics in the Regulations on Laboratory Animals of Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences.

Tuberculosis cutánea verrugosa / Tuberculosis verrucosa cutis

Resumen La tuberculosis es una infección global, con formas pulmonares y extrapulmonares. La tuberculosis cutánea corresponde a 0.5-2% de todas las formas extrapulmonares; la forma verrugosa abarca 8% de todas las formas cutáneas. Es una lesión localizada, de reinfección exógena o por inoculación externa. Por lo general se manifiesta después de un traumatismo sobre la piel; la mayor parte ocurre sobre los dedos y el dorso de las manos. El diagnóstico definitivo requiere el aislamiento del microorganismo por cultivo o secuenciación por PCR, pero hay alta frecuencia de cultivos negativos, por lo que el diagnóstico se establece con base en la correlación clínico-patológica y la respuesta al tratamiento antifímico. El objetivo de este artículo es comunicar un caso de tuberculosis cutánea verrugosa y diferenciar esta afección dermatológica de la provocada por M. marinum por su gran parecido en la manifestación clínica.

Abstract Tuberculosis is a global infection with pulmonary and extrapulmonary forms. Cutaneous tuberculosis corresponds to 0.5-2% of all extrapulmonary forms. The warty form comprises 8% of all cutaneous forms. It is a localized lesion, of exogenous reinfection or external inoculation. Usually, it occurs after a trauma to the skin; most occurring on the fingers and the back of the hands. The definitive diagnosis requires the isolation of the microorganism by culture or sequencing by PCR, but there is a high frequency of negative cultures, so the diagnosis is made based on clinical-pathological correlation and response to antituberculosis treatment. The aim of this article is to report a case of verrucous cutaneous tuberculosis and differentiate this dermatological entity from that caused by M. marinum because of its similarity in clinical presentation.

Disseminated Invasive Mycobacterium marinum Infection Involving the Lung of a Patient with Diabetes Mellitus

Mycobacterium marinum infection in humans occurs mainly as a granulomatous infection after exposure of traumatized skin to contaminated water. It is usually confined to the skin and soft tissue. Disseminated disease involving other organs rarely occurs in immunocompetent patients. Here, we report a case of disseminated M. marinum infection involving not only the cutaneous tissue, but also the lung of a male patient with uncontrolled diabetes and a previous history of steroid injection who was employed by a deep-water fishery.

Disseminated Invasive Mycobacterium marinum Infection Involving the Lung of a Patient with Diabetes Mellitus

Mycobacterium marinum infection in humans occurs mainly as a granulomatous infection after exposure of traumatized skin to contaminated water. It is usually confined to the skin and soft tissue. Disseminated disease involving other organs rarely occurs in immunocompetent patients. Here, we report a case of disseminated M. marinum infection involving not only the cutaneous tissue, but also the lung of a male patient with uncontrolled diabetes and a previous history of steroid injection who was employed by a deep-water fishery.

Pharmaceutical Care for One Case of Mycobacterium Marinum Infection / 中国药师

Taking full advantage of professional knowledge,clinical pharmacist involved in the whole treatment process of one case of mycobacterium infection by assisting doctors in determining and optimizing the anti-infective treatment plan, and performing pharmaceutical care. After the active, rational and effective anti-infective treatment, the patient's infection was controlled effectively. The active participation of clinical pharmacist gains clinical experience for the treatment of rare bacterial infections.

Treatment of Mycobacterium marinum with lymecycline: new therapeutic alternative?

Skin infections by Mycobacterium marinum are quite rare in our environment and, therefore, little studied. The majority of the lesions appear three weeks after traumas in aquariums, beaches and fish tanks. Lymph node drainage and systematization of the disease are rare and most lesions disappear in about three years. This case aims to show the effectiveness of the treatment used (lymecycline 150 mg/orally/day). This medication may be a new therapeutic option for the treatment of Mycobacterium marinum.

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.(AU)

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.

A Clinical, Microbiological, and Pathological Study of Cutaneous Nontuberculous Mycobacterial Infection / 대한피부과학회지

BACKGROUND: As the immunocompromised population has increased in recent years, the number of cutaneous nontuberculous mycobacterial (NTM) infections has also risen. However, since this affliction has no pathognomonic clinical or histological features, the diagnosis and treatment of cutaneous NTM infections are often delayed. OBJECTIVE: The aim of this study was to investigate the microbiological, clinical, and histological findings of cutaneous NTM infections. METHODS: We reviewed medical records and histologic slides of 10 patients diagnosed with cutaneous NTM infections confirmed by culture or polymerase chain reaction. RESULTS: All patients except one were immunocompetent, and 5 of 10 patients had preceding factors including trauma, liposuction, and intralesional triamcinolone injection. Microbiologically, of the 10 infections, 5 were caused by Mycobacterium marinum, 3 by Mycobacterium fortuitum, and 1 each by Mycobacterium chelonae and Mycobacterium ulcerans, respectively. Of the 5 patients with M. marinum, 2 had a fish-related job and 1 reared fish at a home aquarium. The most common clinical presentation was erythematous nodules (7/10). Histologically, irregular acanthosis (4/10), mixed cell infiltrate of lymphocytes, histiocytes, neutrophils (9/10), suppurative granuloma (7/10), microcysts lined by neutrophils (5/10), fibrosis (4/10), and panniculitis (7/10) were identified. CONCLUSION: We found microcysts lined by neutrophils in 50% of the samples and considered this finding to be a diagnostic marker of NTM infection. These clinicopathologic features will assist clinicians in diagnosing NTM infection more rapidly and accurately.

A Case of Mycobacterium marinum Infection Diagnosed by PCR Amplification and Direct Sequencing / 대한피부과학회지

Mycobacterium marinum is an atypical mycobacterium (ATM) and is an uncommon cause of skin and soft tissue infections associated with contact with contaminated water. Diagnosis is often delayed when only a conventional identification method is used. PCR amplification and direct sequencing is recently available method for rapid identification of ATM. We report a case of M. marinum infection identified by PCR and sequencing. A 56-year-old female was referred for multiple erythematous nodules on both forearms which appeared two months ago. Skin biopsy showed suppurative granulomatous inflammation, and AFB culture showed nontuberculous Mycobacteria. PCR and sequencing were performed, and the obtained sequences were compared to the database using BLAST. The sequences of 16S rRNA and rpoB could not differentiate between M. marinum and M. ulcerans, showing 100% homology to both. Identification was possible using the sequences of the tuf and hsp65 genes, showing both 100% homology to M. marinum, while 99.8%, 99.7% to M. ulcerans. The patient was treated with clarithromycin, rifampicin, and ethambutol for 6 months.

Micobacteriose por Mycobacterium marinum em "linguado" Paralichthys orbignyanus e em "barber goby" Elacatinus figaro: diagnóstico histopatológico e imuno-histoquímico / Micobacteriosis by Mycobacterium marinum in Brazilian flounder Paralichthys orbignyanus and barber goby Elacatinus figaro: histopathological and imunohistochemical diagnosis

As micobacterioses afetam várias espécies de peixes, tanto comerciais como ornamentais. É uma enfermidade sistêmica com formação de granulomas, conhecida como micobacteriose de peixes. O desenvolvimento da aquicultura tem aumentado o número de casos com essa enfermidade que muitas vezes é de difícil diagnóstico. Neste trabalho apresentamos dois casos de micobacterioses em Paralichthys orbignyanus e Elacatinus figaro provenientes do Laboratório de Piscicultura Estuarina e Marinha da Universidade Federal do Rio Grande (FURG). As micobactérias de peixes possuem menos ácidos graxos que as de mamíferos, por isso foi utilizado o protocolo de coloração de Fite-Faraco, uma vez que o protocolo de coloração clássico de Ziehl Neelsen pode resultar em falsos negativos. Para determinar o tipo de micobactéria foi utilizada a imuno-histoquímica com a qual se pode diagnosticar a presença de Mycobacterium marinum. A enfermidade pode ser transmitida para o homem e com esse trabalho ressalta-se a necessidade de fazer o diagnóstico correto e implantar medidas de proteção para as pessoas que estão em contato com os peixes infectados.

Mycobacteriosis affects various species of fish, including those cultured with commercial purposes. It is a chronic systemic with granuloma forming disease known as fish mycobacteriosis. In the last few years the interest of fish culture has been increasing due to the reduction of the natural fish stocks. However the intensification of fish culture has collaborated to the development of diseases such as mycobacteriosis, causing losses due to the chronic characteristics and difficult diagnosis. This study is to report two cases of mycobacteriosis observed at "Laboratório de Piscicultura Estuarina e Marinha of the Universidade Federal do Rio Grande (FURG)", one for Brazilian flounder Paralichthys orbignyanus and another for barber goby Elacatinus figaro. The Fite-Faraco staining protocol was used. Membranes of mycobacterial cells contain a waxy substance composed of mycolic acids. These are ß-hydroxy carboxylic acids with chain lengths of up to 90 carbon atoms. The property of acid fastness is related to the carbon chain length of the mycolic acid found in any particular species. The fish mycobacterium is much less acid and alcohol fast than the tubercle bacillus and the classic Ziehl-Neelsen Staining Protocol may give false results. The presence of mycobacterial antigen lesions was studied by immunohistological methods using monoclonal antibodies to Mycobacterium marinum. Humans may be infected by these bacteria and develop cutaneous granuloma. In this paper the necessity is stressed for a correct diagnosis of the disease, contributing to the prevention of its establishment in aquatic facilities, and thus, preserving cultured fish as well as human beings from infection.

A Case of Mycobacterium Marinum Tenosynovitis Diagnosed by the PCR-restriction Fragment Length Polymorphism of the rpoB Gene / 대한내과학회지

Mycobacterium marinum is an uncommon cause of skin and soft-tissue infection. The diagnosis of M. marinum infection is often delayed when only a conventional tissue culture method is used. PCR-restriction fragment length polymorphism (RFLP) analysis using the novel region of the rpoB gene is now available for the rapid identification of Mycobacteria. We report a case of hand infection caused by M. marinum that was identified by PCR-RFLP analysis. The PCR-RFLP assay is a specific and rapid method for the identification of Mycobacteria that facilitates the early diagnosis of non-tuberculous Mycobacterium infection.

A Case of Mycobacterium Marinum Tenosynovitis Diagnosed by the PCR-restriction Fragment Length Polymorphism of the rpoB Gene / 대한내과학회지

Mycobacterium marinum is an uncommon cause of skin and soft-tissue infection. The diagnosis of M. marinum infection is often delayed when only a conventional tissue culture method is used. PCR-restriction fragment length polymorphism (RFLP) analysis using the novel region of the rpoB gene is now available for the rapid identification of Mycobacteria. We report a case of hand infection caused by M. marinum that was identified by PCR-RFLP analysis. The PCR-RFLP assay is a specific and rapid method for the identification of Mycobacteria that facilitates the early diagnosis of non-tuberculous Mycobacterium infection.

A Case of Polyarthritis Caused by Mycobacterium Marinum Infection Mistaken for Rheumatoid Arthritis / 대한류마티스학회지

Mycobacterium marinum (M. marinum) is a nontuberculosis mycobacterium that is normally associated with cutaneous lesions. Most cases occur after an individual has suffered minor trauma in association with contaminated fresh or salt water. In immunocompromised patients, M. marinum can cause osteomyelitis, synovitis and/or disseminated infection, which can be mistaken for rheumatoid arthritis (RA) or remitting seronegative symmetrical synovitis with pitting edema (RS3PE). Therefore, precise history taking and specimen culture are very important for early diagnosis and appropriate treatment. We report an unusual case of septic polyarthritis due to M. marinum that was diagnosed by culture and improved with antibiotic therapy.

A Case of Sporotrichoid Cutaneous Infection Caused by Mycobacterium marinum

Mycobacterium marinum is a nontuberculous mycobacterium responsible for skin infection. Risk factors include a history of trauma and water/fish-related hobbies or occupations. This infection is characteristically limited to the skin but deep soft tissue may be involved. We report a case of M. marinum infection in a 51-year-old man with ulcer and erythematous nodules on his right hand. The patient owned a tropical fish tank and remembered having previous hand trauma. The lesions extended to his forearm and formed sporotrichoid appearance. M. marinum was isolated from tissue specimens. The patient was treated with rifampin, etambutol and clarithromycin for 5 months, then the skin lesions were cured. The key to the diagnosis of this case are clinical awareness and a detailed history. M. marinum infection should be considered in chronic sporotrichoid skin lesions, particularly when there is a clinical suspicion on an infectious cause, and it could lead to successful treatment.

A Case of Sporotrichoid Cutaneous Infection Caused by Mycobacterium marinum

Mycobacterium marinum is a nontuberculous mycobacterium responsible for skin infection. Risk factors include a history of trauma and water/fish-related hobbies or occupations. This infection is characteristically limited to the skin but deep soft tissue may be involved. We report a case of M. marinum infection in a 51-year-old man with ulcer and erythematous nodules on his right hand. The patient owned a tropical fish tank and remembered having previous hand trauma. The lesions extended to his forearm and formed sporotrichoid appearance. M. marinum was isolated from tissue specimens. The patient was treated with rifampin, etambutol and clarithromycin for 5 months, then the skin lesions were cured. The key to the diagnosis of this case are clinical awareness and a detailed history. M. marinum infection should be considered in chronic sporotrichoid skin lesions, particularly when there is a clinical suspicion on an infectious cause, and it could lead to successful treatment.