Bacteriology (Gram Positive Bacilli)

Corynebacterium diphtheriae

A Gram (+) bacilli isolated from the human nasopharynx, not part of normal flora.

Listeria monocytogenes

Another type of Gram (+) bacilli.

Non-spore forming

Characteristic of Corynebacterium diphtheriae.

Catalase (+)

Indicates the presence of the enzyme catalase in Corynebacterium diphtheriae.

Non-branching

Describes the morphology of Corynebacterium diphtheriae.

Club-shaped

Common shape of Corynebacterium diphtheriae.

Chinese character

Refers to the arrangement of Corynebacterium diphtheriae cells.

Picket-fence

Another term describing the arrangement of Corynebacterium diphtheriae.

Pleomorphic

Describes the variable shapes of Corynebacterium diphtheriae.

Lipophilic

A characteristic of Corynebacterium diphtheriae.

Urease (-)

Indicates that Corynebacterium diphtheriae does not produce urease.

Non-aerobic and motile

Incorrect characteristics for Corynebacterium diphtheriae, which is aerobic and nonmotile.

Metachromatic granules

Inclusion bodies found in Corynebacterium diphtheriae.

Respiratory form

The most common form of disease caused by Corynebacterium diphtheriae.

Bull's neck

Appearance associated with the respiratory form of diphtheria.

Cutaneous form

A form of diphtheria common in tropical regions.

Ecthyma diphtheriticum

Initial ulcerative lesion associated with Corynebacterium diphtheriae.

BAP

Blood Agar Plate, a culture medium for Corynebacterium diphtheriae.

Tinsdale Agar

A specific culture medium for Corynebacterium diphtheriae.

Loeffler's Serum Agar

Media useful for morphology and demonstration of metachromatic granules in Corynebacterium diphtheriae.

CTB Agar

Preferred medium for Corynebacterium diphtheriae, a modification of Tinsdale medium.

Black, Gunmetal colonies

Colony morphology of Corynebacterium diphtheriae on CTBA.

Narrow zone of B-hemolysis

Colony morphology of Corynebacterium diphtheriae on BAP.

Black colonies with brown halo

Colony morphology of Corynebacterium diphtheriae on Tinsdale Medium.

Gravis

Biotype of Corynebacterium diphtheriae with the largest colony type.

Mitis

Biotype of Corynebacterium diphtheriae with fried egg colony appearance on BAP.

Intermedius

Biotype of Corynebacterium diphtheriae with small, gray, translucent colonies.

Animal inoculation using guinea pigs

In vivo test for diphtheria toxin.

Modified Elek Test

In vitro test for diphtheria toxin.

Vero Cell Cytotoxicity Assay

Gold standard for diphtheria toxin production.

PCR

Molecular method used for testing Corynebacterium diphtheriae.

Schick's Test

Skin test for susceptibility to diphtheria.

C

A species of Corynebacterium that causes prosthetic device infections.

Metallic sheen

Appearance of C. jeikeium on BAP.