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ILAR Journal 2012Mycobacteriosis, a chronic bacterial infection, has been associated with severe losses in some zebrafish facilities and low-level mortalities and unknown impacts in...
Mycobacteriosis, a chronic bacterial infection, has been associated with severe losses in some zebrafish facilities and low-level mortalities and unknown impacts in others. The occurrence of at least six different described species (Mycobacterium abscessus, M. chelonae, M. fortuitum, M. haemophilum, M. marinum, M. peregrinum) from zebrafish complicates diagnosis and control because each species is unique. As a generalization, mycobacteria are often considered opportunists, but M. haemophilum and M. marinum appear to be more virulent. Background genetics of zebrafish and environmental conditions influence the susceptibility of fish and progression of disease, emphasizing the importance of regular monitoring and good husbandry practices. A combined approach to diagnostics is ultimately the most informative, with histology as a first-level screen, polymerase chain reaction for rapid detection and species identification, and culture for strain differentiation. Occurrence of identical strains of Mycobacterium in both fish and biofilms in zebrafish systems suggests transmission can occur when fish feed on infected tissues or tank detritus containing mycobacteria. Within a facility, good husbandry practices and sentinel programs are essential for minimizing the impacts of mycobacteria. In addition, quarantine and screening of animals coming into a facility is important for eliminating the introduction of the more severe pathogens. Elimination of mycobacteria from an aquatic system is likely not feasible because these species readily establish biofilms on surfaces even in extremely low nutrient conditions. Risks associated with each commonly encountered species need to be identified and informed management plans developed. Basic research on the growth characteristics, disinfection, and pathogenesis of zebrafish mycobacteria is critical moving forward.
Topics: Animals; Biofilms; Fish Diseases; Mycobacterium; Mycobacterium Infections; Mycobacterium chelonae; Zebrafish
PubMed: 23382341
DOI: 10.1093/ilar.53.2.95 -
BMC Infectious Diseases Mar 2023Mycobacterium haemophilum is a slow-growing non-chromogenic nontuberculous Mycobacterium species that can cause skin infection or arthritis in an immunocompromised...
BACKGROUND
Mycobacterium haemophilum is a slow-growing non-chromogenic nontuberculous Mycobacterium species that can cause skin infection or arthritis in an immunocompromised population or in children. Primary infection of the healthy adult cornea is rare. The special requirements for culture make this pathogen difficult to diagnose. The study aims to report the clinical manifestation and treatment process of corneal infection and notify the awareness of M. Haemophilus keratitis among clinicians. This is the first case report of primary M. haemophilum infection in the cornea of healthy adults reported in the literature.
CASE PRESENTATION
A 53-year-old healthy goldminer presented with left eye redness and a history of vision loss for four months. The patient was misdiagnosed with herpes simplex keratitis until M. haemophilum was detected using high-throughput sequencing. Penetrating keratoplasty was performed, and a large number of mycobacteria were detected by Ziehl-Neelsen staining of the infected tissue. Three months later, the patient developed conjunctival and eyelid skin infections that manifested as caseous necrosis of the conjunctiva and skin nodules. After excision and debridement of the conjunctival lesions and systemic antituberculosis drug treatment for 10 months, the patient was cured.
CONCLUSION
M. haemophilum could cause primary corneal infection in healthy adults, which is an infrequent or rare infection. Owing to the need for special bacterial culture conditions, conventional culture methods do not provide positive results. High-throughput sequencing can rapidly identify the presence of bacteria, which aids in early diagnosis and timely treatment. Prompt surgical intervention is an effective treatment option for severe keratitis. Long-term systemic antimicrobial therapy is crucial.
Topics: Adult; Child; Humans; Middle Aged; Mycobacterium haemophilum; Cornea; Eye Infections; Nontuberculous Mycobacteria; Skin
PubMed: 36882753
DOI: 10.1186/s12879-023-08094-2 -
Microbiology Spectrum Jun 2022Leprosy is caused by Mycobacterium leprae and Mycobacterium . We report construction and analyses of the complete genome sequence of FJ924. The genome contained...
Leprosy is caused by Mycobacterium leprae and Mycobacterium . We report construction and analyses of the complete genome sequence of FJ924. The genome contained 3,271,694 nucleotides to encode 1,789 functional genes and 1,564 pseudogenes. It shared 1,420 genes and 885 pseudogenes (71.4%) with M. leprae but differed in 1,281 genes and pseudogenes (28.6%). In phylogeny, the leprosy bacilli started from a most recent common ancestor (MRCA) that diverged ~30 million years ago (Mya) from environmental organism Mycobacterium haemophilum. The MRCA then underwent reductive evolution with pseudogenization, gene loss, and chromosomal rearrangements. Analysis of the shared pseudogenes estimated the pseudogenization event ~14 Mya, shortly before species bifurcation. Afterwards, genomic changes occurred to lesser extent in each species. Like M. leprae, four major types of highly repetitive sequences were detected in , contributing to chromosomal rearrangements within and after MRCA. Variations in genes and copy numbers were noted, such as three copies of the gene encoding bifunctional diguanylate cyclase/phosphodiesterase in , but single copy in M. leprae; 6 genes encoding the TetR family transcriptional regulators in , but 11 such genes in M. leprae; presence of gene in , but absence in M. leprae; and others. These variations likely aid unique pathogenesis, such as diffuse lepromatous leprosy associated with , while the shared genomic features should explain the common pathogenesis of dermatitis and neuritis in leprosy. Together, these findings and the genomic data of may facilitate future research and care for leprosy. Leprosy is a dreaded infection that still affects millions of people worldwide. Mycobacterium is a recently recognized cause in addition to the well-known Mycobacterium leprae. is likely specific for diffuse lepromatous leprosy, a severe form of the infection and endemic in Mexico. This study constructed and annotated the complete genome sequence of FJ924 and performed comparative genomic analyses with related mycobacteria. The results afford new and refined insights into the genome size, gene repertoire, pseudogenes, phylogenomic relationship, genome organization and plasticity, process and timing of reductive evolution, and genetic and proteomic basis for pathogenesis. The availability of the complete genome may prove to be useful for future research and care for the infection.
Topics: Humans; Leprosy; Leprosy, Lepromatous; Mycobacterium; Mycobacterium leprae; Proteomics
PubMed: 35467405
DOI: 10.1128/spectrum.01692-21 -
Emerging Infectious Diseases Sep 2008The database of a major microbiology laboratory in Israel was searched to determine the prevalence of nontuberculous mycobacterial lymphadenitis in immunocompetent...
The database of a major microbiology laboratory in Israel was searched to determine the prevalence of nontuberculous mycobacterial lymphadenitis in immunocompetent children. We observed a 4-fold increase in nontuberculous mycobacteria isolates during 1985-2006, which was attributable mainly to increased detection of Mycobacterium haemophilum starting in 1996.
Topics: Adolescent; Child; Child, Preschool; Female; Humans; Immunocompetence; Infant; Israel; Lymphadenitis; Male; Mycobacterium Infections; Mycobacterium avium Complex; Mycobacterium haemophilum
PubMed: 18760014
DOI: 10.3201/eid1409.070917 -
Journal of the American Veterinary... Dec 2023
Topics: Animals; Oryzias; Fish Diseases
PubMed: 37699544
DOI: 10.2460/javma.23.07.0409 -
Journal of Fish Diseases Jun 2020The use of zebrafish (Danio rerio) in biomedical research has expanded at a tremendous rate over the last two decades. Along with increases in laboratories using this... (Review)
Review
The use of zebrafish (Danio rerio) in biomedical research has expanded at a tremendous rate over the last two decades. Along with increases in laboratories using this model, we are discovering new and important diseases. We review here the important pathogens and diseases based on some 20 years of research and findings from our diagnostic service at the NIH-funded Zebrafish International Resource Center. Descriptions of the present status of biosecurity programmes and diagnostic and treatment approaches are included. The most common and important diseases and pathogens are two parasites, Pseudoloma neurophilia and Pseudocapillaria tomentosa, and mycobacteriosis caused by Mycobacterium chelonae, M. marinum and M. haemophilum. Less common but deadly diseases are caused by Edwardsiella ictaluri and infectious spleen and kidney necrosis virus (ISKNV). Hepatic megalocytosis and egg-associated inflammation and fibroplasia are common, apparently non-infectious, in zebrafish laboratories. Water quality diseases include supersaturation and nephrocalcinosis. Common neoplasms are spindle cell sarcomas, ultimobranchial tumours, spermatocytic seminomas and a small-cell carcinoma that is caused by a transmissible agent. Despite the clear biosecurity risk, researchers continue to use fish from pet stores, and here, we document two novel coccidia associated with significant lesions in zebrafish from one of these stores.
Topics: Animals; Animals, Laboratory; Communicable Disease Control; Fish Diseases; Oregon; Research; Zebrafish
PubMed: 32291793
DOI: 10.1111/jfd.13165 -
International Journal of... Dec 2016Mycobacterium haemophilum is a slow-growing nontuberculous mycobacterium (NTM) that can cause ulcerating cutaneous or subcutaneous nodular skin lesions in...
INTRODUCTION
Mycobacterium haemophilum is a slow-growing nontuberculous mycobacterium (NTM) that can cause ulcerating cutaneous or subcutaneous nodular skin lesions in immunocompromised and immunocompetent patients. Acid-fast staining cannot distinguish NTM from M. tuberculosis; culturing at two temperatures with iron-supplemented media and polymerase chain reaction (PCR) are needed for optimal detection of M. haemophilum.
CASE PRESENTATION
A 32-year-old man with end-stage renal disease, undergoing hemodialysis twice a week, presented with multiple, painless, nonpruritic nodular lesions. A formalin-fixed paraffin-embedded tissue block from his finger lesion was sent to the Department of Pathology, Masih Daneshvari Hospital for consultation. The lesions were primarily diagnosed to be dermatofibroma by another pathologist. On microscopic examination, vague granuloma with areas of necrosis was observed. The diagnosis was established by positive acid-fast staining, negative PCR results for M. tuberculosis complex, and positive nested PCR results for M. haemophilum.
CONCLUSION
Cutaneous lesions in immunocompromised patients with positive results in acid-fast staining and negative results for M. tuberculosis should be further assessed using skin culture and molecular techniques to identify rare, atypical mycobacterial species like M. haemophilum.
PubMed: 28043577
DOI: 10.1016/j.ijmyco.2016.09.024 -
Antimicrobial Agents and Chemotherapy Oct 1995An animal model of disseminated Mycobacterium haemophilum infection was utilized to compare treatment with azithromycin, ciprofloxacin, rifabutin, and the combination of...
An animal model of disseminated Mycobacterium haemophilum infection was utilized to compare treatment with azithromycin, ciprofloxacin, rifabutin, and the combination of clarithromycin with rifabutin. Following subcutaneous challenge with M. haemophilum, local and disseminated infection occurred only in immunosuppressed mice. For disseminated infection, ciprofloxacin was relatively ineffective therapy. Clarithromycin and rifabutin alone significantly reduced the tissue burden in the spleen after 4 weeks of therapy. Combination therapy with rifabutin and clarithromycin was superior to 4 weeks of treatment with the individual agents. When immunosuppressed mice were treated for 20 weeks with the combination of rifabutin and clarithromycin, the tissue burden remained reduced in the spleen at 1 month following the completion of therapy. Combined rifabutin and clarithromycin provide effective treatment for M. haemophilum in this model.
Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Ciprofloxacin; Clarithromycin; Drug Therapy, Combination; Male; Mice; Mice, Inbred BALB C; Mice, Inbred ICR; Mice, Nude; Mycobacterium Infections; Mycobacterium haemophilum; Rifabutin
PubMed: 8619588
DOI: 10.1128/AAC.39.10.2316 -
Emerging Infectious Diseases 1999Although most diseases due to pathogenic mycobacteria are caused by Mycobacterium tuberculosis, several other mycobacterial diseases-caused by M. ulcerans (Buruli... (Review)
Review
Although most diseases due to pathogenic mycobacteria are caused by Mycobacterium tuberculosis, several other mycobacterial diseases-caused by M. ulcerans (Buruli ulcer), M. marinum, and M. haemophilum-have begun to emerge. We review the emergence of diseases caused by these three pathogens in the United States and around the world in the last decade. We examine the pathophysiologic similarities of the diseases (all three cause necrotizing skin lesions) and common reservoirs of infection (stagnant or slow-flowing water). Examination of the histologic and pathogenic characteristics of these mycobacteria suggests differences in the modes of transmission and pathogenesis, though no singular mechanism for either characteristic has been definitively described for any of these mycobacteria.
Topics: Disease Reservoirs; Fasciitis, Necrotizing; Humans; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Risk Factors; Skin Ulcer
PubMed: 10341173
DOI: 10.3201/eid0503.990307 -
Zebrafish Feb 2019In 2017, the zebrafish unit at University of Glasgow experienced a detrimental outbreak of pathogenic bacterium, Mycobacterium haemophilum. The presence of other...
In 2017, the zebrafish unit at University of Glasgow experienced a detrimental outbreak of pathogenic bacterium, Mycobacterium haemophilum. The presence of other bacterial species was also confirmed by bacteriology growth in the same unit. The affected individuals composed of a wild-origin parental population sourced from India and their F1 offspring generation. Bacteria were diagnostically confirmed to be present systemically in fish and within the water and biofilm of the recirculating zebrafish system. In the absence of a publicly accessible step-by-step disinfectant protocol for these difficult-to-eliminate pathogens, we devised a successful procedure to eradicate mycobacteria and Aeromonas species after colony removal using Cleanline Chlorine tablets (active ingredient Sodium dichloroisocyanurate) and Virkon Aquatic. Postdisinfection diagnostics did not detect pathogens in the system or in the new fish inhabiting the system that were tested. Newly established fish colonies have not shown similar clinical signs or disease-induced mortality in the 1-year period following system disinfection and repopulation. We present a historical background of the bacterial outbreak and a disinfection method which can be replicated in other zebrafish facilities-at small or large scales-for reliable mycobacterium removal. This procedure can be implemented as a disinfection protocol before the introduction of a new fish population to a previously contaminated system.
Topics: Animals; Disease Eradication; Disease Outbreaks; Disinfectants; Disinfection; Fish Diseases; Mycobacterium Infections; Mycobacterium haemophilum; Zebrafish
PubMed: 30358522
DOI: 10.1089/zeb.2018.1628