Micobacteriose em camarão branco do pacífico, Litopenaeus vannamei / Mycobacteriosis white shrimp pacific Litopenaeus vannamei

A infecção por Mycobacterium spp. tem sido constatada em diversos vertebrados, ocasionando doenças em humanos e animais. As espécies responsáveis pela ocorrência de micobacteriose em peixes, a saber, Mycobacterium marinum, M. fortuitum e M. chelonae, também são potencialmente infecciosas para os camarões peneídeos. A micobacteriose que afeta crustáceos corresponde a uma enfermidade sistêmica, granulomatosa, possuindo como agente etiológico bacilos Gram positivos ácido-álcool resistentes. Relata-se neste trabalho a ocorrência de micobacteriose em camarões da espécie Litopenaeus vannamei, sendo identificada a bactéria M. marinum nas amostras teciduais analisadas. Durante a manutenção de juvenis da espécie foram observadas lesões enegrecidas no sexto segmento abdominal de 20 espécimes. A partir das técnicas de Fite-Faraco e Fluorescence In Situ Hybridization (FISH) foi identificado o patógeno, representando uma doença bacteriana com potencial zootécnico que ocorre em ambientes aquáticos, acarretando riscos de contaminação tópica em pessoas envolvidas na manipulação de camarões.(AU)

The Mycobacterium spp. infection they have been documented in many vertebrates, causing known diseases in man and animals. The species responsible for the occurrence of mycobacteriosis in fish, Mycobacterium marinum, M. fortuitum and M. chelonae, are also potentially infectious for penaeid shrimp. The mycobacterial disease that affects shellfish corresponds to a systemic disease, granulomatous, having as an etiological agent Gram-positive bacilli resistant acid-alcohol. We report the occurrence of mycobacteriosis in shrimps of the species Litopenaeus vannamei, and identified the species M. marinum in tissue samples analyzed. During the maintenance of juvenile of the species, blackish lesions were observed in the sixth abdominal segment in 20 specimens. From techniques Fite-Faraco and hybridization in situ with fluorescence (FISH), has identified the pathogen in the analyzed tissue was observed, representing a bacterial disease of aquatic environments with zoonotic potential, causing risks of topical contamination on people involved in handling shrimp.(AU)

Micobacteriose em camarão branco do pacífico, Litopenaeus vannamei / Mycobacteriosis white shrimp pacific Litopenaeus vannamei

A infecção por Mycobacterium spp. tem sido constatada em diversos vertebrados, ocasionando doenças em humanos e animais. As espécies responsáveis pela ocorrência de micobacteriose em peixes, a saber, Mycobacterium marinum, M. fortuitum e M. chelonae, também são potencialmente infecciosas para os camarões peneídeos. A micobacteriose que afeta crustáceos corresponde a uma enfermidade sistêmica, granulomatosa, possuindo como agente etiológico bacilos Gram positivos ácido-álcool resistentes. Relata-se neste trabalho a ocorrência de micobacteriose em camarões da espécie Litopenaeus vannamei, sendo identificada a bactéria M. marinum nas amostras teciduais analisadas. Durante a manutenção de juvenis da espécie foram observadas lesões enegrecidas no sexto segmento abdominal de 20 espécimes. A partir das técnicas de Fite-Faraco e Fluorescence In Situ Hybridization (FISH) foi identificado o patógeno, representando uma doença bacteriana com potencial zootécnico que ocorre em ambientes aquáticos, acarretando riscos de contaminação tópica em pessoas envolvidas na manipulação de camarões.

The Mycobacterium spp. infection they have been documented in many vertebrates, causing known diseases in man and animals. The species responsible for the occurrence of mycobacteriosis in fish, Mycobacterium marinum, M. fortuitum and M. chelonae, are also potentially infectious for penaeid shrimp. The mycobacterial disease that affects shellfish corresponds to a systemic disease, granulomatous, having as an etiological agent Gram-positive bacilli resistant acid-alcohol. We report the occurrence of mycobacteriosis in shrimps of the species Litopenaeus vannamei, and identified the species M. marinum in tissue samples analyzed. During the maintenance of juvenile of the species, blackish lesions were observed in the sixth abdominal segment in 20 specimens. From techniques Fite-Faraco and hybridization in situ with fluorescence (FISH), has identified the pathogen in the analyzed tissue was observed, representing a bacterial disease of aquatic environments with zoonotic potential, causing risks of topical contamination on people involved in handling shrimp.

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.(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.

Detection of mycobacteria in ornamental fish in Iran by culture and Ziehl-Neelsen staining methods

Background: Mycobacterial infections in fish is largely chronic to subacute in nature and affects fishes in fresh water, brackish water and salt water. In addition to their known infectivity to fishes, aquatic mycobacteria pose significant zoonotic concerns. Due to the zoonotic character of the disease, increasing importance of aquariology, and lack of any clinical signs in early steps of mycobacteriosis, present study was undertaken to analyze the distribution of mycobacteria in diseased and apparently healthy ornamental fish from some local aquarium fish shops in four different cities in Iran by culture and Ziehl-Neelsen staining. Materials, Methods & Results: One hundred and one fresh water aquarium fish of 22 species from some local shops in four cities in Iran were examined. Before decontamination, smears of homogenized samples stained with Ziehl-Neelsen. For bacterial culture, samples were inoculated on Lowenstein-Jensen medium. Culture plates were examined daily for four weeks. The rate of growth at different temperature, colony morphology and pigmentation were evaluated for species identification. Among 79 moribund fish examined, 16 individuals were positive for acid fast rods at microscopic examination. Seven fish out of 22 apparently healthy individuals also gave positive microscopic results. Using the culture method, 29 and 10 Mycobacterium isolates were obtained from moribund and healthy fish. The following Mycobacterium species were isolated from unhealthy fish: Mycobacterium fortuitum, M. marinum, and M. smegmatis. The number of different species of Mycobacterium from apparently healthy fish was: M. fortuitum (one fish), M. marinum (one fish), M. terrae (one fish) and M. flavescens (one fish). Discussion: Based on the results in both moribund and apparently healthy fish examined, culture examination showed more mycobacteria than Ziehl-Neelsen staining detection. Lower proportion of Ziehl-Neelsen positive results compared with culture method was reported in aquarium fish in Slovania. Using positive microscopic results, 13 isolates were obtained where as 29 samples gave positive culture results for mycobacteria. Similar result was also observed in clinically healthy ornamental fish and their aquarium environment. The identification of mycobacteria by Ziehl-Neelsen staining is a traditional method. However, acid-fast bacilli may not always be found through direct microscopy because the destruction of mycobacteria or their low number may sometimes happen. Culture examination is a more sensitive method than direct microscopy. However, killing of mycobacteria caused by host defense mechanisms, a low number of viable mycobacteria in the tissue, or by destruction of the mycobacteria during the preparation of the sample could result in negative cultivation results. Species of Mycobacterium identified in unhealthy fish were M. fortuitum, M. marinum and M. smegmatis. High frequency of identifying M. fortuitum and M. marinum (6 out of 7) in the samples provide more evidence that these species are common Mycobacterium species to be found in diseased aquarium fish. Numerous studies showed the common isolation of these two species from aquarium fish. M. marinum infection may be an occupational hazard for certain professionals such as pet shop workers. Many infections may also occur in fish fanciers who keep an aquarium at home. Less common than M. marinum, M. fortuitum is also capable of infecting human. In this study, the occurrence of M. marinum and M. fortuitum in both unhealthy and apparently healthy aquarium fish shows the importance of recognizing fish mycobacteriosis in order to prevent their transmission to human.