Mycobacterium avium avium

Mycobacterium avium is a slow growing bacteria, the three known subspecies ( subspecies ) are all pathogens.

The nominate Mycobacterium avium ssp. avium is the causative agent of avian tuberculosis, Mycobacterium avium ssp. paratuberculosis is the causative agent of paratuberculosis in cattle and possibly also involved in the development of Crohn's disease in humans. Mycobacterium avium ssp. silvaticum also triggers from tuberculosis in birds and Para tuberculosis in mammals.

Features

Mycobacterium avium is rod-shaped, the surface of cultures is smooth or rough. Most known strains are not photochromogen, a few are skotochromogen and a pale yellow color. Required for their growth are temperatures around 37 ° C.

System

Mycobacterium avium belongs to the so-called MAIS complex within the genus ( Mycobacterium avium intracellulare scrofulaceum ), whose species due to many common characteristics only by genetic analyzes ( 16S rRNA) can be distinguished from each other. As important features of the pathogenicity and the host range apply.

Pathogenicity

Mycobacterium avium takes a special position, because on the one hand causes the poultry tuberculosis, on the other hand, in humans or mammals occurs as pathogens. The highest susceptibility own chickens, followed by doves, birds of prey and waterfowl. It can also occur in small birds / pets. The pathogen is also absorbed through the food chain, such as rats. Infections in humans or mammals, are referred to as mycobacterioses. They occur most likely to occur in cattle and pigs and act, inter alia, as the causative agent of mastitis in cows. The pathogen belongs to the non - tuberculous mycobacteria can occur in tap water is up to 140 ° C heat- resistant (ie, not by boiling eliminated ) and can cause in people with weakened immune systems dangerous lung infections with tuberculosis - like symptoms. The pathogen is particularly dangerous because it is often not diagnosed and do not affect conventional broad-spectrum antibiotics. For prophylaxis azithromycin is given. As proved effective combination therapy of isoniazid and high-dose cefpodoxime.

Evidence

  • Marie- Francoise Thorel, Micah Krichevsky, Veronique Vincent Levy- Frebault: Numerical Taxonomy of mycobactin -dependent mycobacteria, emended Description of Mycobacterium avium, and Mycobacterium avium subsp Description of. avium subsp. nov., Mycobacterium avium subsp. paratuberculosis subsp. nov., and Mycobacterium avium subsp. sylvaticum subsp. nov, In: . International Journal of Systematic and Evolutionary Microbiology, 1990, 40, pp. 254-260
  • Sybe Hartmans Jan De Bont AM, Erko Stackebrandt: The Genus Mycobacterium - nonmedical, In: The Prokaryotes, 3:889-918, 2006 doi: 10.1007/0-387-30743-5_33
Actinobacteria Actinomycetales Digital Object Identifier
589294
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