What is the Difference Between Corynebacterium Diphtheriae and Diphtheroids?

Corynebacterium diphtheriae and diphtheroids are both types of bacteria belonging to the Corynebacterium genus. However, they have distinct characteristics and differences:

• Cell morphology: Diphtheroids are aerobic, non-sporulating, pleomorphic Gram-positive bacilli that are more uniformly stained than Corynebacterium diphtheriae and lack metachromatic granules. Corynebacterium diphtheriae contains metachromatic granules in polar regions.
• Arrangement: Diphtheroids are arranged in a palisade manner.
• Habitat: Diphtheroids are usually commensals of the skin and mucous membranes.
• Pathogenicity: Corynebacterium diphtheriae is a pathogenic bacterium that causes diphtheria, a severe respiratory illness. Diphtheroids, on the other hand, can be either pathogenic or non-pathogenic bacteria.
• Biochemical reactions: Diphtheroids differ from C. diphtheriae in biochemical reactions and toxin production.
• Identification: In routine diagnostic practice, diphtheroids are commonly considered as contaminants from the skin and are not usually identified to the species level.
• Antimicrobial resistance: Some Corynebacterium species, such as C. amycolatum, C. jeikeium, C. minutissimum, C. pseudodiphtheriticum, C. resistens, C. striatum, C. tuberculostearicum, and C. urealyticum, have been reported to exhibit antimicrobial resistance. However, multidrug resistance among the infrequently recovered Corynebacterium species is rarely observed.

Comparative Table: Corynebacterium Diphtheriae vs Diphtheroids

Corynebacterium diphtheriae and diphtheroids are both types of bacteria belonging to the Corynebacterium genus. Here is a table highlighting the differences between the two:

Corynebacterium diphtheriae is a pathogenic bacterium that causes diphtheria, while diphtheroids are a group of bacteria that can be either pathogenic or non-pathogenic. Diphtheroids lack metachromatic granules and are more uniformly stained than Corynebacterium diphtheriae. Additionally, diphtheroids differ from Corynebacterium diphtheriae in biochemical reactions and toxin production.