Background
- Thanks to childhood vaccination against tetanus, tetanus is now extremely rare in the UK (only 3-8 cases/year)
- The causative organism, Clostridium tetani, is a spore-forming gram-positive obligate anaerobe which can grow in necrotic tissue, infected tissue or in foreign bodies. There is produces tetanospasmin toxin which can spread via blood/lymph and can cause irreversible damage to neurons, causing characteristic muscle spasm/rigidity
- Spores may be found in garden soils/manure, rusty metals
- Incubation time can be 7-10 days
Presentation
- Classically presents with generalised (descending) tetanus
- Trismus (lockjaw) and risus sardonicus (grimace of the face)
- Neck stiffness/spasticity (can develop into opisthotonus- arched body with hyperextended neck)
- Swallowing problems, abdominal rigidity and muscle spasms may also develop
- Spasms (initially reflexive, then spontaneous) can last seconds to minutes and can be painful and exhausting
- Patients often die of complications of these e.g. exhaustion, aspiration pneumonia or asphyxia
Diagnosis is usually clinical and rarely are any investigations required for diagnosis.
Management
Tetanus
- Give human tetanus immunoglobulin first
- Debride any wounds after a few hours (risk of toxin spread)
- Benzypenicillin 600mg IV QDS is often used (metronidazole if allergic)
- IV diazepam may help control spasms, if not- consider paralysing the patient and ventilating
Tetanus prone wounds (far more common)
- These are wounds/burns sustained >6 hours before surgical treatment or on with
- a significant degree of devitalised tissue or a puncture wound
- especially if there has been contact with soil/manure
- foreign bodies
- compound fractures
- clinical evidence of sepsis
- a significant degree of devitalised tissue or a puncture wound
- If the wound is high risk (i.e. deep wound or known to be contaminated with soil/manure/rust), patient should be given anti tetanus immunoglobulin
- If the patient has not been vaccinated it is recommended that the patient also receive anti-tetanus toxoid also
- If the wound is tetanus-prone but not high risk, IM anti-toxoid (250IU/5ml/750mg) should be given
- Thorough wound debridement and cleansing is important