Mycobacterium lepraemurium

Mycobacterium lepraemurium is the causative agent of feline leprosy. It causes granulomatous lesions, characteristic of the Mycobacterium genus.

Description
Gram-positive, nonmotile and strongly acid-fast rods (3-5µm long). Slightly rounded ends.

Colony characteristics
 * Rough nonchromogenic colonies.

Physiology
 * Growth on inspissated 1% egg yolk medium at 30°C - 37°C within 4-5 weeks (using large inocula, confined to a concentrated area of the medium, egg white is inhibitory).

Pathogenesis

 * Cause of endemic disease of rats in various parts of the world, as well as feline leprosy.
 * feline leprosy is transmitted by bites from rats and other cats.
 * Disease occurs mainly in the skin and lymph nodes, causing induration, alopecia and eventual ulceration.
 * Nodular lesions, involving subcutaneous tissues, may be solitary or multiple and usually confined to the head region or the limbs. Nodules are fleshy and freely movable.
 * Surgical excision of the lesions is the preferred treatment.
 * Only the densely and uniformly stained forms appear to be infectious for animals, in contrast to the degenerate unevenly stained forms.


 * Biosafety level 2

Type Strain
None specified due to difficulties in cultivation.