|Staphylococcus intermedius Gram-stained cells
|Staphylococcus intermedius NCTC 11048 hemolytic
colonies on sheep blood agar
Phylum Firmicutes, Class Bacilli, Order Bacillales, Family Staphylococcaceae, Genus Staphylococcus, Staphylococcus intermedius
Hajek 1976. Historical synonym: Staphylococcus aureus var. canis Meyer 1966.
Gram-positive cocci, 0.5-1.5 μm in diameter, nonmotile, nonsporing, occuring singly
or grouped in pairs and clusters.
Colonies are white-cream, 5.0-6.5 mm in diameter, S-type colonies. Facultatively
anaerobic. Optimum growth temperatature is 37 ºC (also grow at 15 & 45 ºC). Can
grow on Trypticase Soy Agar ± 5% sheep blood, Trypticase Soy Broth, Chapman agar,
P agar. Hemolysis is variable.
Bacteria was isolated from horse, dog, cat, mink, rat, mouse, pigeon & other birds
(from skin, nose, pharynx, ears, conjunctive, vagina, intestine). Frequent inhabitant of
dog skin and can be transferred to the skin of human handlers. Rarely was isolated
from humans. Sensible to novobiocin and lysostaphin. Resistant to lysozyme.
In animals: dermatitis, otitis, conjunctivitis, urinary infections, pneumonia, abscesses, peritonitis, mastitis. Exfoliative toxin involved in
dermatitis. May be a normal resident in the canine nasal cavity, oropharynx, and the perianal region. In humans may produce wound
infections (dog bite infections), food poisoning (enterotoxins A, B, C, D, E). Opportunistic pathogen in immunocompromised patients.
- Holt J.G., Krieg N.R., Sneath P.H.A., Staley J.T., Wiliams S.T., 1994. Bergey's Manual of Determinative Bacteriology, Ninth Edition,
Williams & Wilkins, Baltimore. Group 17, Gram-Positive Cocci, 527-558.
- Hajek V.: Staphylococcus intermedius, a new species isolated from animals. International Journal of Systematic Bacteriology,
1976, 26, 401-408.
- Devriese L.A. & Hajek V. : Identification of pathogenic staphylococci isolated from animals and foods derived from animals. J.
Appl. Bacteriol., 1980, 49, 1-11.
- Karsten Becker, Birgit Keller, Christof von Eiff, Michaela Brück, Gabriele Lubritz, Jerome Etienne, & Georg Peters: Enterotoxigenic
Potential of Staphylococcus intermedius. Applied and Environmental Microbiology, December 2001, p. 5551-5557, Vol. 67, No. 12.
- Karl-Heinz Schleifer and Julia A. Bell, 2009. Family VIII. Staphylococcaceae fam. nov.. In: (Eds.) P.D. Vos, G. Garrity, D. Jones, N.R.
Krieg, W. Ludwig, F.A. Rainey, K.-H. Schleifer, W.B. Whitman. Bergey’s Manual of Systematic Bacteriology, Volume 3: The
Firmicutes, Springer, 392-426.
Positive results for nitrate reduction, alkaline phosphatase, urease, heat-stable
nuclease, gelatinase, coagulase-rabbit plasma, deoxyribonuclease, catalase, methyl
red test, acid production from: trehalose, fructose, glucose, glycerol, sucrose and
Negative results for oxidase, hyaluronidase, fibrinolysin, beta-glucuronidase, acetoin
production, esculin hydrolysis, indole production, H2S, protein A, tellurite reduction,
acid production from: xylitol, raffinose, xylose, arabinose, cellobiose, fucose, salicin
Variable results for clumping factor, beta-galactosidase, beta-glucosidase, arginine
dihydrolase, coagulation of human plasma, hemolysin, acid production from: lactose,
mannitol and turanose.
Admin note: API Staph kit cannot identify Staphylococcus intermedius. If you are
getting the message <<Staphylococcus aureus …. possibility of S. intermedius if of
veterinary origin>> and your sample is harvested from an animal it doesn’t mean that
the strain is automatically S. intermedius. You need to perform additional tests to
(c) Costin Stoica