Phylum Actinobacteria, Class Actinobacteria, Order Actinomycetales, Suborder Corynebacterineae, Family Mycobacteriaceae, Genus
Mycobacterium, Mycobacterium heidelbergense Haas et al. 1998.
Member of the Mycobacterium simiae complex.
Acid-alcohol-fast coccobacilli, 2.0-3.0 x 0.5-0.8 μm. Pleomorphic forms may occur, up
to 8.0 μm in length. Does not produce aerial hyphae, capsules, or spores.
Colonies are eugonic, dome-shaped, smooth, non-pigmented, and 0.5-1.0 mm in
diameter. Temperature range for growth is 30-37 ºC; optimal growth is at 33-35 ºC;
does not grow at 25 or 45 ºC. However, colonies may be observed on Middlebrook
7H11 agar at temperatures ranging between 25 and 45 ºC. Visible growth from dilute
inocula appears in 3-4 weeks.Does not grow on media supplemented with 5% (w/v)
Isolated from cervical lymph node tissue of a child suffering from lymphadenitis, in Heidelberg, Germany.
Susceptible to rifampin (1 μg/ml), isoniazid (1 μg/ml), ethambutol (2 μg/ml), and streptomycin (2 μg/ml).
Has been identified as the cause of cervical lymphadenitis in a child.
- John G. Magee and Alan C. Ward 2012. Family III. Mycobacteriaceae Chester 1897, 63AL in Bergey’s Manual of Systematic
Bacteriology, Volume Five The Actinobacteria, Part A, Michael Goodfellow & al. (editors), 312-375.
- Haas WH, Butler WR, Kirschner P, Plikaytis BB, Coyle MB, Amthor B, Steigerwalt AG, Brenner DJ, Salfinger M, Crawford JT, et al. A
new agent of mycobacterial lymphadenitis in children: Mycobacterium heidelbergense sp. nov. J Clin Microbiol 1997; 35:3203-
Positive results for heat-stable catalase (68 ºC), pyrazinamidase, Tween 80 hydrolysis, and urea hydrolysis.
Negative results for acid phosphatase, arylsulphatase (3 days), catalase activity at 22 ºC, semiquantitative catalase test, niacin
accumulation, and nitrate reduction.
(c) Costin Stoica