Tetanus

Last revised by Dr Daniel J Bell on 04 May 2022

Tetanus is a rare vaccine-preventable disease caused by Clostridium tetani, a ubiquitous soil bacterium which contaminates open wounds. It secretes a powerful neurotoxin which degrades neuromuscular junction function, producing muscle spasms and, despite intensive intervention, is often fatal.

Tetanus is often thought of as a historical disease in the developed world, due to widespread successful vaccination. However occasional cases still do occur, and it remains a significant cause of death in Africa, accounting for almost 45,000 fatalities in 2015 1. It has been estimated that there are still one million cases of tetanus each year 3.

With no modern medical treatment, mortality approaches 100% 3.

The C tetani spores are ubiquitous in the outside environment globally and contamination of open wounds is an ever present danger. In neonates there is a risk of infection of the umbilical stump 1.

  • older adults (> 60 years): vaccination less likely
  • IVDU

Clostridium tetani, a Gram-positive anaerobic bacterium, is ubiquitous globally as a spore in the soil. 

When local conditions are anaerobic, the C tetani spores reproduce as vegetative bacteria which secrete tetanospasmin, an exotoxin, one of the most powerful neurotoxins ever studied 1,3.

Classically, tetanus is characterized by tetanic spasms, which are spasms of all or localized groups of muscles (up to 4/5 cases); this often manifests initially as a feeling of muscle stiffness 1:

  • generalized
  • limb-specific
  • head and neck region: cephalic tetanus
    • cranial nerve palsies
    • facial muscle spasms
      • trismus (impaired mandibular movement)
      • risus sardonicus (fixed facial grimace)
    • laryngeal and/or pharyngeal muscles
      • airway compromise
      • aspiration
    • extensor muscles: opisthotonus
    • abdominal muscles
      • rigidity is characteristic

Other features:

  • dysphagia (~80%)
  • fever, >38·4°C (75%)
  • autonomic involvement, often episodic 1,3
    • tachycardia (35%), hypertension, diaphoresis
    • bradycardia and hypotension also seen
  • breathlessness (<10%)
  • sensory nerve involvement (uncommon)
    • allodynia, paresthesia, hyperalgesia

Tetanus disease severity is most commonly graded by the Ablett classification 1.

Generally neuroimaging is unremarkable in tetanus.

to be completed

Tetanus is derived from the Greek word τέτανος (tetanos) meaning a "muscle spasm", itself derived from the verb τείνω (teino) meaning "stretch" 2.

ADVERTISEMENT: Supporters see fewer/no ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.