Mycobacterium spp.
Mycobacterium spp. is a topic covered in the Johns Hopkins HIV Guide.
To view the entire topic, please sign in or purchase a subscription.
Official website of the Johns Hopkins Antibiotic (ABX), HIV, Diabetes, and Psychiatry Guides, powered by Unbound Medicine. Johns Hopkins Guide App for iOS, iPhone, iPad, and Android included. Explore these free sample topics:
-- The first section of this topic is shown below --
MICROBIOLOGY
- Mycobacteria spp. divided into rapid growers (< 7 days) and slow growers (>7 days) based on time to mature growth on agar plates.
- Rapid grower: M. fortuitum: (3-7 days) and M. chelonae. Slow growing: M. gordonae (7-10 days), M. malmoense, M. marinum (7-10 days), M. ulcerans and M. xenopi (3-8 wks in Cx), M. terrae, M. nonchromogenicum, (also: M. kansasii, M. avium-intracellulare, M. tuberculosis, not covered in this module).
- M. genavense: very slow growing. Alert lab: requires incubation in broth media for ≥8 wks.
- M. haemophilum: "blood-loving," slow growing. Alert lab: requires ferric iron supplementation and temperature 30oC.
- Risk for non-tuberculous mycobacterial (NTM) disease in HIV+ pts directly proportional to CD4 count. Invasive non-TB disease rare with CD4 count >50 (except for M. marinum) and Sx usually chronic (>30 d) prior to Dx. High CD4 and short duration of Sx make NTM unlikely cause of illness; in this setting positive sputum isolates more likely to be colonizers or contaminants.
-- To view the remaining sections of this topic, please sign in or purchase a subscription --
MICROBIOLOGY
- Mycobacteria spp. divided into rapid growers (< 7 days) and slow growers (>7 days) based on time to mature growth on agar plates.
- Rapid grower: M. fortuitum: (3-7 days) and M. chelonae. Slow growing: M. gordonae (7-10 days), M. malmoense, M. marinum (7-10 days), M. ulcerans and M. xenopi (3-8 wks in Cx), M. terrae, M. nonchromogenicum, (also: M. kansasii, M. avium-intracellulare, M. tuberculosis, not covered in this module).
- M. genavense: very slow growing. Alert lab: requires incubation in broth media for ≥8 wks.
- M. haemophilum: "blood-loving," slow growing. Alert lab: requires ferric iron supplementation and temperature 30oC.
- Risk for non-tuberculous mycobacterial (NTM) disease in HIV+ pts directly proportional to CD4 count. Invasive non-TB disease rare with CD4 count >50 (except for M. marinum) and Sx usually chronic (>30 d) prior to Dx. High CD4 and short duration of Sx make NTM unlikely cause of illness; in this setting positive sputum isolates more likely to be colonizers or contaminants.
There's more to see -- the rest of this entry is available only to subscribers.