Tetanus is caused by a toxin from Clostridium tetani, a bacterium that enters through wounds and blocks the nerves that normally let muscles relax. The result is painful stiffness and spasms that can stop breathing, and it is almost fully preventable with vaccination.
Key symptoms
- Jaw stiffness and trouble opening the mouth (lockjaw)
- Neck stiffness, trouble swallowing and a fixed grin
- Painful muscle spasms set off by noise, touch or light
- Arched back, sweating and a racing heart
What you find on exam
- A recent wound, often a puncture, burn or dirty cut
- Rigid jaw and abdominal muscles with a clear mind
- Spatula test: the patient bites down on a tongue blade instead of gagging
- Swings in heart rate, blood pressure and temperature
- Breathing effort and airway during spasms
Tests
- Diagnosis is clinical; no blood test confirms it
- Tetanus vaccine history
- Basic labs, creatine kinase and kidney function for muscle breakdown
- Rule out mimics: strychnine poisoning, drug reactions, low calcium
Treatment basics
- Protect the airway early; intubate if spasms affect breathing
- Human tetanus immune globulin plus a tetanus vaccine dose
- Clean and debride the wound; metronidazole as the antibiotic
- Benzodiazepines such as diazepam or midazolam for spasms, in a quiet, dark room
- Magnesium and ICU care for autonomic instability
Red flags
- Throat or chest spasms that make breathing hard
- Large swings in heart rate or blood pressure
- Lockjaw after a wound in someone not up to date on vaccines
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.