Corynebacterium diphtheriae

Gram Stain

• Gram positive bacilli irregular club shaped (aerobic)

Clinical Significance

Toxigenic strains can cause pharyngeal diphtheria, cutaneous diphtheria, or endocarditis.

Note: Culture for C. diphtheriae only performed by special request (contact microbiologist).

Non toxigenic strains have been associated with septicemia, endocarditis, bone/joint infections, brain abscesses, and endophthalmitis.

Usual Susceptibility Pattern

Diphtheria antitoxin is the mainstay of therapy.

Antimicrobial therapy is of secondary importance for patient but is useful in the prophylaxis of contacts.

These organisms are typically susceptible to penicillin and macrolides.