Clinical Significance of Mycobacterium asiaticum Isolates in Queensland, Australia

Abstract

Mycobacterium asiaticum was first reported as a cause of human disease in 1982, with only a few cases in the literature to date. This study aims to review the clinical significance of M. asiaticum isolates in Queensland, Australia. A retrospective review (1989 to 2008) of patients with M. asiaticum isolates was conducted. Data were collected through the Queensland TB Control Centre database. Disease was defined in accordance with the American Thoracic Society criteria. Twenty-four patients (13 female) had a positive culture of M. asiaticum, many residing around the Tropic of Capricorn. M. asiaticum was responsible for pulmonary disease (n ‫؍‬ 2), childhood lymphadenitis (n ‫؍‬ 1), olecranon bursitis (n ‫؍‬ 1), 6 cases of possible pulmonary disease, and 2 possible wound infections. Chronic lung disease was a risk factor for pulmonary infection, and wounds/ lacerations were a risk factor for extrapulmonary disease. Extrapulmonary disease responded to local measures. Pulmonary disease responded to ethambutol-isoniazid-rifampin plus pyrazinamide for the first 2 months in one patient, and amikacin-azithromycin-minocycline in another patient. While M. asiaticum is rare in Queensland, there appears to be an environmental niche. Although often a colonizer, it can be a cause of pulmonary and extrapulmonary disease. Treatment of pulmonary disease remains challenging. Extrapulmonary disease does not mandate specific nontuberculous mycobacterium (NTM) treatment.

Molecular Identification of Nontuberculous Mycobacteria in Humans in Zimbabwe Using 16S Ribosequencing

“…This rare NTM species was recently isolated from water supplies [ 32 ]. M. asiaticum is regarded as a cause of pulmonary disease, childhood lymphadenitis, olecranon bursitis and wound infections [ 33 ]. M. moriokaense species was shown to be associated with chronic pneumonia [ 34 ].…”

A case of pulmonary infection caused by Mycobacterium asiaticum: Difficulties on diagnostic and therapeutic approaches

“…According to data from published literatures, M. asiaticum causes infection in several organs including respiratory and musculoskeletal system [ 2 ]. This organism has a predilection for a tropical climate and is commonly found in environmental water [ 2 ]. Exposure to this natural source is the likely mode of transmission, and there is no published evidence suggesting person-to-person transmission.…”

“…Thirdly, M. asiaticum partially responded to the standard anti-tuberculous regimen. Moreover, according to the reported case of Grech et al [ 2 ], prolonged treatment was necessitated to eradicate the organism and prevent relapse of the infection. Our patient took medications for 18 months without clinical relapse during the 10 year follow-up period.…”

“…Its isolate shows photochromogenic like M. kansasii and M. marinum , which can be differentiated by molecular methods. Although M. asiaticum is rarely isolated and a frequent colonizer, it is established to cause both pulmonary and extrapulmonary diseases in human [ 2 ]. Patients infected with M. asiaticum possibly have the same predisposing factors as those infected with other NTM species.…”

Draft Genome Sequence of Mycobacterium asiaticum Strain DSM 44297

“…M. asiaticum has been isolated in monkeys ( 3 ) and pigs ( 4 ). In humans, M. asiaticum isolates have been obtained from respiratory tract specimens ( 5 , 6 ), lyphadenitis, bursitis, and wound specimens ( 7 ), and keratitis samples ( 8 ). In respiratory tract specimens, it is mainly recognized as a harmless contaminant but a few patients have been documented with M. asiaticum pneumonia ( 2 , 9 ).…”