Clostridium tetani (tetanus)


This is a clinical diagnosis supported by electrophysiological features

Clinical features:

Tetany: lockjaw (trismus), wrinkled forehead (frontalis), closed eyes (orbicularis oculi), retracted lips (resus sardonicus), contracted bulbar muscles, neck, limbs, rigidity, board-like abdomen
Spasms: opsotonos, paroxysms of contraction, pharyngeal/laryngeal spasms,
Diaphoresis, BP swings
Localised tetany: rigidity and spasms localised to one part of the body, near a wound. If localised to the head it’s called cephalic tetanus

Findings on investigations:


  • Spasm: Continuous discharges of normal motor units
  • Loss of physiologic silent period after contraction (50-100ms). Best found in masseter.

CK: normal or slightly raised


Antitoxin (tetanus immune human globulin)
Penicillin 10days, Metronidazole or tetracycline
Treatment of the wound

  • Airway management
  • Neuromuscular blocking agent
  • Benzodiazepines

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