Diphtheria

Introduction. 

Diphtheria is a respiratory infection by Corynebacterium diphtheriae. Although coryneform bacteria are common to the human respiratory tract, C. diphtheriae is particularly pathogenic due to the presence of a lysogenic bacteriophage encoding the diphtheria toxin. 

Summary

• Cause: Corynebacterium diphtheriae
• Microscopy: Club-shaped, irregular Gram-positive rods; parallel (palisade) arrangement
• Symptoms: Pharyngitis; Pseudomembrane in throat
• Complications:  Myocarditis, neurotoxicity
• Transmission: Respiratory
• Pathogenesis: Diphtheria exotoxin: inhibits EF-2, kills cell
• Treatment: Antitoxin, penicillin, erythromycin
• Prevention: Vaccine