What is Tellurite agar used for?
Tellurite Blood Agar is a selective medium used for isolation and cultivation of Corynebacterium species (1, 2). It is selective due to the presence of inhibitor and differential by means of ability of organism to reduce potassium tellurite.
Which selective medium is used for isolation of Corynebacterium diphtheriae?
For primary isolation, a variety of media may be used: Loeffler agar, Mueller-Miller tellurite agar, or Tinsdale tellurite agar. Sterile cotton-tipped applicators are used to swab the pharyngeal tonsils or their beds.
Which medium offers a better growth for Corynebacterium diphtheriae?
diphtheriae grows well on blood agar, but tellurite blood agar (Hoyle’s medium) is recommended as this inhibits other respiratory flora and allows the characteristic colonial morphology of the three biotypes (gravis, intermedius and mitis) to develop.
What Agar does Corynebacterium grow on?
Tinsdale agar (TIN) is used for the primary isolation and identification of Corynebacterium diphtheriae. The medium differentiates between C. diphtheriae and diphtheroids found in the upper respiratory tract.
What is tellurite medium?
Tellurite Blood Agar is a selective medium used for the isolation and cultivation of Corynebacterium species. It is selective due to the presence of inhibitors and differential by means of the ability of organisms to reduce potassium tellurite.
What is the purpose of potassium tellurite in cystine tellurite blood agar?
Potassium tellurite is also a selective agent which inhibits a variety of gram-positive and gram-negative bacteria other than Corynebacterium spp.
Which is the selective medium for Corynebacterium?
A new selective medium for isolation of Corynebacterium kutscheri (CK) from animals suffering subclinical infection was made by adding furazolidone, nalidixic acid and corimycin to the heart infusion agar base, this being named FNC agar.
Does Corynebacterium diphtheriae grow on MacConkey Agar?
The presence of coryneform organisms in smears is diagnostic. Culture on blood agar, selective blood agar and MacConkey agar are also diagnostic, they do not grow on MacConkey.
What is the purpose of potassium tellurite in cystine tellurite Blood Agar?
Does Corynebacterium grow on MacConkey Agar?
Diagnosis. To diagnose the Corynebacterium species, samples include pus, exudate, affected tissues and urine. The presence of coryneform organisms in smears is diagnostic. Culture on blood agar, selective blood agar and MacConkey agar are also diagnostic, they do not grow on MacConkey.
Which staining is used for identification of Corynebacterium diphtheriae?
Gram stain
To accurately identify C. diphtheriae, a Gram stain is performed to show Gram-positive, highly pleomorphic organisms with no particular arrangement. Special stains like Albert’s stain and Ponder’s stain are used to demonstrate the metachromatic granules formed in the polar regions.
What does tellurite mean?
Definition of tellurite 1 : a salt of tellurous acid. 2 : a mineral TeO2 that consists of tellurium dioxide and occurs sparingly in tufts of white or yellowish crystals.
Does Corynebacterium diphtheriae grow on tellurite?
Corynebacterium diphtheriae on tellurite agar. Tellurite Blood Agar is a selective medium used for isolation and cultivation of Corynebacterium species. Potassium tellurite acts as a selective agent and has inhibitory activity against most gram-positive and gram-negative bacteria except Corynebacterium species.
What is the best test for the diagnosis of diphtheria?
Classical and modified Elek tests are commonly used to demonstrate the toxigenicity of C. diphtheriae, C. ulcerans, and C. pseudotuberculosis strains. Moreover, a rapid immunochromatographic method for detection of diphtheria toxin has been developed.
What is tellurite blood agar used for?
Tellurite Blood Agar is a selective medium used for isolation and cultivation of Corynebacterium species. Potassium tellurite acts as a selective agent and has inhibitory activity against most gram-positive and gram-negative bacteria except Corynebacterium species. C.diphtheriae reduces potassium…
How much tell tellurium do you give a person?
Tellurium (IV) had to be given at a dose of 100 μmol/kg body weight to give the same effect. At a dose of 10 μmol Te (IV) per kg body weight, the mercury retention ratios (treated:control) were 140 for the lung and 8.6 for the whole body.