Corynebacterium diphtheriae

Corynebacterium diphtheriae is a Gram-positive, non-motile, non-capsulated, club-shaped bacillus responsible for diphtheria, a serious infectious disease that primarily affects the mucous membranes of the respiratory tract or skin. Its pathogenicity is largely due to a potent exotoxin (diphtheria toxin) encoded by a bacteriophage-borne gene (tox). Toxigenic strains colonize the upper respiratory tract or skin, forming a pseudomembrane and releasing toxin systemically, which can lead to severe complications including myocarditis and neuropathy. Laboratory diagnosis relies on culture, toxin detection, and PCR-based identification. Infection is prevented with vaccination (diphtheria toxoid), and treated with antitoxin and antibiotics such as penicillin or erythromycin. Drug-resistant strains have emerged, highlighting ongoing challenges in management[1][3][4][5].

Other names

Klebs–Löffler bacillusKlebs-Loeffler bacillus

For antitoxin, neutralization of diphtheria toxin; for antibiotics, inhibition of bacterial cell wall synthesis (penicillin), inhibition of protein synthesis (erythromycin)[4]