Mycobacterium conceptionense

Mycobacterium conceptionense is a non pigmented rapidly growing mycobacterium was first isolated from wound liquid outflow, bone tissue biopsy, and excised skin tissue from a 31-year-old woman who suffered an accidental open right tibia fracture and prolonged stay in a river. Etymology: conceptionense, pertaining to Hôpital de la Conception, the hospital where the first strain was isolated.

Description

Microscopy

• Acid-fast and gram-positive bacilli.

Colony characteristics

• Colonies are non pigmented.

Physiology

• Colonies appear on 5% sheep blood agar, Middlebrook 7H10 agar, and egg-based Lowenstein-Jensen slants in 2 to 5

days at temperatures between 25 and 37°C, optimally at 30°C. No growth occurs at 42°C.

• The type strain is susceptible in vitro to imipenem, minocycline, doxycycline, clarithromycin, erythromycin, azithromycin, amikacin, ciprofloxacin, ofloxacin, sparfloxacin, and amoxicillinclavulanate and resistant to penicillin, amoxicillin, and vancomycin.

Differential characteristics

• M. conceptionense shares 99.7% 16S rRNA (4-bp difference) and 97.0% rpoB gene sequence similarity with Mycobacterium porcinum, the nearest species.

Pathogenesis

• This species is associated with post traumatic osteitis.

Type strain

• Strain D16 = CCUG 50187 = CIP 108544

References

• Adékambi,T., et al. 2006. Description of Mycobacterium conceptionense sp. nov., a Mycobacterium fortuitum group organism isolated from a posttraumatic osteitis inflammation. J. Clin. Microbiol., 44, 1268-1273. PMID 16597850