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Clinical Microbiology Reviews Jan 2018Humans encounter mycobacterial species due to their ubiquity in different environmental niches. In many individuals, pathogenic mycobacterial species may breach our... (Review)
Review
Humans encounter mycobacterial species due to their ubiquity in different environmental niches. In many individuals, pathogenic mycobacterial species may breach our first-line barrier defenses of the innate immune system and modulate the activation of phagocytes to cause disease of the respiratory tract or the skin and soft tissues, sometimes resulting in disseminated infection. Cutaneous mycobacterial infections may cause a wide range of clinical manifestations, which are divided into four main disease categories: (i) cutaneous manifestations of infection, (ii) Buruli ulcer caused by and other related slowly growing mycobacteria, (iii) leprosy caused by and , and (iv) cutaneous infections caused by rapidly growing mycobacteria. Clinically, cutaneous mycobacterial infections present with widely different clinical presentations, including cellulitis, nonhealing ulcers, subacute or chronic nodular lesions, abscesses, superficial lymphadenitis, verrucous lesions, and other types of findings. Mycobacterial infections of the skin and subcutaneous tissue are associated with important stigma, deformity, and disability. Geography-based environmental exposures influence the epidemiology of cutaneous mycobacterial infections. Cutaneous tuberculosis exhibits different clinical phenotypes acquired through different routes, including via extrinsic inoculation of the tuberculous bacilli and dissemination to the skin from other sites, or represents hypersensitivity reactions to infection. In many settings, leprosy remains an important cause of neurological impairment, deformity, limb loss, and stigma. , a mycobacterial species related to , is linked to diffuse lepromatous leprosy of Lucio and Latapí. produces a mycolactone toxin that leads to subcutaneous tissue destruction and immunosuppression, resulting in deep ulcerations that often produce substantial disfigurement and disability. , a close relative of , is an important cause of cutaneous sporotrichoid nodular lymphangitic lesions. Among patients with advanced immunosuppression, , the complex, and may cause cutaneous or disseminated disease. Rapidly growing mycobacteria, including the group, , and , are increasingly recognized pathogens in cutaneous infections associated particularly with plastic surgery and cosmetic procedures. Skin biopsies of cutaneous lesions to identify acid-fast staining bacilli and cultures represent the cornerstone of diagnosis. Additionally, histopathological evaluation of skin biopsy specimens may be useful in identifying leprosy, Buruli ulcer, and cutaneous tuberculosis. Molecular assays are useful in some cases. The treatment for cutaneous mycobacterial infections depends on the specific pathogen and therefore requires a careful consideration of antimicrobial choices based on official treatment guidelines.
Topics: Animals; Dermatitis; Humans; Mycobacterium; Mycobacterium Infections
PubMed: 30429139
DOI: 10.1128/CMR.00069-18 -
Microbiology Spectrum Nov 2016The list of clinically important slow-growing nontuberculous mycobacteria (NTM) continues to expand as new species are identified and older ones are found to be... (Review)
Review
The list of clinically important slow-growing nontuberculous mycobacteria (NTM) continues to expand as new species are identified and older ones are found to be pathogenic. Based on pigment production, the strains may be classified as photochromogenic, scotochromogenic, or unpigmented. Some of these organisms are not newly discovered but have heretofore been considered virtually nonpathogenic. Previously, many were regarded as contaminants when isolated from clinical specimens. Ubiquitous in nature, many NTM have been isolated from groundwater or tap water, soil, house dust, domestic and wild animals, and birds. Most infections result from inhalation or direct inoculation from environmental sources. They are not spread from person to person. The infections may be localized or disseminated. In most cases, the optimal regimen or duration of therapy has not been firmly established. The results of in vitro susceptibility testing may be used to select a therapeutic regimen. Many experts recommend clarithromycin with companion drugs such as rifampin and ethambutol for most, but not all, slowly growing species. Aminoglycosides, clofazimine, fluoroquinolones, linezolid, pyrazinamide, or trimethoprim-sulfamethoxazole also may be effective against some strains. Immunocompetent patients with clinically significant infections with NTM usually should receive 18 to 24 months of therapy. Infected immunocompromised patients, particularly those with disseminated infection, probably should receive therapy as long as their immune systems remain impaired. Some of the species discussed include Mycobacterium alsiense, M. celatum, M. gordonae, M. haemophilum, M. kyorinense, M. malmoense, M. simiae complex, M. szulgai, M. terrae complex, M. ulcerans, and M. xenopi.
Topics: Anti-Bacterial Agents; Antitubercular Agents; Environmental Microbiology; Humans; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Rifampin
PubMed: 27837745
DOI: 10.1128/microbiolspec.TNMI7-0012-2016 -
Journal of Clinical Tuberculosis and... Aug 2017is an uncommonly encountered acid-fast staining bacillus (AFB) that can cause a broad range of infections. We describe a tertiary care center's experience with... (Review)
Review
is an uncommonly encountered acid-fast staining bacillus (AFB) that can cause a broad range of infections. We describe a tertiary care center's experience with infections identified from 2000 to 2015. Ten adult patients were identified with infections, and most had immunocompromising conditions. presented in one of two syndromes: a peripheral cutaneous infection presenting with skin nodularity and local invasion, and a cervicofacial infection involving regional lymph nodes. Duration of therapy was variable (0-18 months) and was dependent on the underlying syndrome and immunological status of the patient. Treatment responses were favorable in all patients. During therapy, three patients developed culture-negative aseptic cutaneous lesions, consistent with immunologic reconstitution inflammatory syndrome (IRIS); we postulate that such reactions may not be uncommon with select infections.
PubMed: 31723708
DOI: 10.1016/j.jctube.2017.06.002 -
BMC Ophthalmology Sep 2020Mycobacterium haemophilum is a rare and emerging nontuberculous mycobacteria (NTM). It normally causes localized or disseminated systemic diseases, particularly skin... (Review)
Review
BACKGROUND
Mycobacterium haemophilum is a rare and emerging nontuberculous mycobacteria (NTM). It normally causes localized or disseminated systemic diseases, particularly skin infections and arthritis in severely immunocompromised patients. There have been 5 cases of M. haemophilum ocular infections reported in the literature. Only 1 case presented with scleritis with keratitis. Here, we reported 2 cases of M. haemophilum scleritis. One of them was immunocompetent host and had keratitis with radial keratoneuritis as a presenting sign.
CASE PRESENTATION
Case 1: A 52-year-old Thai female with rheumatoid arthritis presented with scleritis. Conjunctival scraping was carried out and the culture result was positive for M. haemophilum. Despite receiving systemic and topical antibiotics, her clinical symptoms and signs worsened. Surgical debridement was performed. After surgery, the lesion was significantly improved and finally turned to conjunctival scarring. Case 2: A 32-year old healthy Thai male without underlying disease presented with nodular scleritis and keratouveitis with multiple radial keratoneuritis. Surgical debridement of the scleral nodule was performed. Initial microbiological investigations were negative. Herpes ocular infections was suspected. Topical antibiotics, oral acyclovir, low-dose topical steroids and systemic steroids were started. The scleral inflammation subsided but later the keratitis relapsed, requiring corneal biopsy. Histopathology of the specimen revealed acid-fast bacteria and M. haemophilum was identified by polymerase chain reaction (PCR) and sequencing. The diagnosis of Mycobacterial keratitis was made. Although using the combination of systemic and topical antibiotics, his clinical status progressively deteriorated. Multiple therapeutic penetrating keratoplasties were required to eradicate the infection. No recurrence was found during the 1-year follow-up in both cases.
CONCLUSIONS
M. haemophilum can cause scleritis and keratitis, even in immunocompenent host. Radial keraoneuritis is first described in M. haemophilum keratitis. NTM keratitis should be considered in the differential diagnosis of patients with radial keratoneuritis. Increased awareness and early diagnosis using appropriate culture conditions and molecular techniques are important for the proper treatment of this infection. Prompt surgical intervention appears to be vital for successful management of M. haemophilum scleritis and keratitis.
Topics: Adult; Eye Infections, Bacterial; Female; Humans; Keratitis; Male; Middle Aged; Mycobacterium Infections; Mycobacterium haemophilum; Scleritis
PubMed: 32967654
DOI: 10.1186/s12886-020-01649-w -
Emerging Infectious Diseases Sep 2019Mycobacterium haemophilum is a nontuberculous mycobacterium that can infect immunocompromised patients. Because of special conditions required for its culture, this...
Mycobacterium haemophilum is a nontuberculous mycobacterium that can infect immunocompromised patients. Because of special conditions required for its culture, this bacterium is rarely reported and there are scarce data for long-term outcomes. We conducted a retrospective study at Siriraj Hospital, Bangkok, Thailand, during January 2012-September 2017. We studied 21 patients for which HIV infection was the most common concurrent condition. The most common organ involvement was skin and soft tissue (60%). Combination therapy with macrolides and fluoroquinolones resulted in a 60% cure rate for cutaneous infection; adding rifampin as a third drug for more severe cases resulted in modest (66%) cure rate. Efficacy of medical therapy in cutaneous, musculoskeletal, and ocular diseases was 80%, 50%, and 50%, respectively. All patients with central nervous system involvement showed treatment failures. Infections with M. haemophilum in HIV-infected patients were more likely to have central nervous system involvement and tended to have disseminated infections and less favorable outcomes.
Topics: Adult; Aged; Anti-Bacterial Agents; Cohort Studies; Female; HIV Infections; Humans; Immunocompromised Host; Male; Middle Aged; Mycobacterium Infections; Mycobacterium haemophilum; Retrospective Studies; Thailand; Treatment Outcome
PubMed: 31441427
DOI: 10.3201/eid2509.190430 -
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 -
Journal of the American Veterinary... Dec 2023
Topics: Animals; Oryzias; Fish Diseases
PubMed: 37699544
DOI: 10.2460/javma.23.07.0409 -
BMC Infectious Diseases Jan 2021Ruxolitinib is a novel oral Janus kinase inhibitor that is used for treatment of myeloproliferative diseases. It exhibits potent anti-inflammatory and immunosuppressive... (Review)
Review
BACKGROUND
Ruxolitinib is a novel oral Janus kinase inhibitor that is used for treatment of myeloproliferative diseases. It exhibits potent anti-inflammatory and immunosuppressive effects, and may increase the risk of opportunistic infections. Here, we report a rare case of Cryptococcus neoformans and Mycobacterium haemophilum coinfection in a myelofibrosis patient who was receiving ruxolitinib.
CASE PRESENTATION
A 70-year-old Thai man who was diagnosed with JAK2V617F-mutation-positive primary myelofibrosis had been treated with ruxolitinib for 4 years. He presented with cellulitis at his left leg for 1 week. Physical examination revealed fever, dyspnea, desaturation, and sign of inflammation on the left leg and ulcers on the right foot. Blood cultures showed positive for C. neoformans. He was prescribed intravenous amphotericin B deoxycholate with a subsequent switch to liposomal amphotericin B due to the development of acute kidney injury. He developed new onset of fever after 1 month of antifungal treatment, and the lesion on his left leg had worsened. Biopsy of that skin lesion was sent for mycobacterial culture, and the result showed M. haemophilum. He was treated with levofloxacin, ethambutol, and rifampicin; however, the patient eventually developed septic shock and expired.
CONCLUSIONS
This is the first case of C. neoformans and M. haemophilum coinfection in a patient receiving ruxolitinib treatment. Although uncommon, clinicians should be aware of the potential for multiple opportunistic infections that may be caused by atypical pathogens in patients receiving ruxolitinib.
Topics: Aged; Amphotericin B; Anti-Bacterial Agents; Anti-Inflammatory Agents, Non-Steroidal; Antifungal Agents; Cellulitis; Coinfection; Cryptococcosis; Cryptococcus neoformans; Deoxycholic Acid; Drug Combinations; Fungemia; Humans; Male; Mycobacterium Infections; Mycobacterium haemophilum; Nitriles; Opportunistic Infections; Primary Myelofibrosis; Pyrazoles; Pyrimidines
PubMed: 33413168
DOI: 10.1186/s12879-020-05703-2