Tetanus is caused by toxins from clostridium tetani, a gram positive anaerobic bacillus found in soil.
Classically tetanus occurs following inoculation into a deep wound, but in 30% of cases no entry point is identified. Incubation varies from 24 hours to several months; shorter incubation heralds more severe disease.
Clinical features include:
- Trismus – inability to open mouth due to rigidity of masseters – often the first symptom
- Neck stiffness
- Risus sardonicus
- Widespread rigidity and spasms - can be severe enough to cause laryngeal obstruction and death
Diagnosis is clinical – culturing c.tetani is difficult.
Treatment
- Tetanus immunoglobulin
- IV Metronidazole – preferably PR as causes fewer muscle spasms
- Supportive – muscle relaxants, possibly intubation
- It is a notifiable disease
Prevention
Vaccinations at 2,3 and 4 months, then preschool, then a further booster 10 years after the preschool jab. Thereafter, if a patient has had all their childhood vaccinations (5 doses of tetatnus vaccine), they should never need a booster. The vaccine is not live.
Immunoglobulin should be given to patients presenting with a wound heavily contaminated with material likely to contain tetanus spores which is defined as a ‘tetanus prone wound’. The definition of a tetanus-prone wounds is:
- Wounds/burns that require surgical intervention that is delayed for more than 6 hours
- Wounds/burns with significant devitalized tissue or puncture-type injury
- Wounds containing foreign bodies
- Compound fractures
- Wounds/burns in patients with systemic sepsis.
Mortality from tetanus is around 50% in developing countries. In developed countries this is around 15%.
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