TETANUS

Bacterial disease characterised by intermittent spasms (twitching) of voluntary muscles. Incubation period is from few days to few weeks (average7-10 days).

Cause

  • Exotoxin of Clostridium tetani
  • Common sources of infection: tetanus spores enter the body through deep penetrating skin wounds, the umbilical cord of the newborn, ear infection, or wounds produced during delivery and septic abortions

Clinical features

  • Stiff jaw, difficulty in opening mouth (trismus)
  • Generalised spasms induced by sounds and/or strong light, characterised by grimace (risus sardonicus)
  • Arching of back (opisthotonus) with the patient remaining clearly conscious
  • Fever
  • Glottal spasms and difficulty in breathing
  • Absence of a visible wound does not exclude tetanus

Differential diagnosis

  • Meningoencephalitis, meningitis
  • Phenothiazine side-effects
  • Febrile convulsions

Management

General measures

  • Nurse patient intensively in a quiet isolated area
  • Maintain close observation and attention to airway, temperature, and spasms
  • Insert nasogastric tube (NGT) for nutrition, hydration, and medicine administration
  • Oxygen therapy if needed
  • Prevent aspiration of fluid into the lungs
  • Avoid IM injections as much as possible; use alternative routes (e.g. NGT, rectal) where possible
  • Maintain adequate nutrition as spasms result in hugh metabolic demands
  • Treat respiratory failure in ICU with ventilation

Neutralise toxin

  • Give tetanus immunoglobulin human (TIG)
    • 150 IU/kg (adults and children). Give the dose in at least 2 different sites IM, different from the tetanus toxoid site
  • In addition, administer full course of age appropriate
    TT vaccine (TT or DPT) – starting immediately

Treatment to eliminate source of toxin

  • Clean wounds and remove necrotic tissue.

First line antibiotics

  • Metronidazole 500 mg every 8 hours IV or by mouth for 7 days
    Child: 7.5 mg/kg every 8 hours

Second line antibiotics

  • Benzylpenicillin 2.5 MU every 6 hours for 10 days
    Child: 50,000-100,000 IU/kg per dose

Control muscle spasms

First line

  • Diazepam 10 mg (IV or rectal) every 1 to 4 hours
  • Child: 0.2 mg/kg IV or 0.5 mg/kg rectal (maximum of 10 mg) every 1 to 4 hours

Other agents

  • Magnesium sulphate (alone or with diazepam): 5 g (or 75 mg/kg) IV loading dose then 2 g/hour till spasm control is achieved
    • Monitor knee-jerk reflex, stop infusion if absent
  • Or chlorpromazine (alone or alternate with diazepam) 50-100 mg IM every 4-8 hours
    Child: 4-12 mg IM every 4-8 hours or
  • 12.5 mg-25 mg by NGT every 4-6 hours
    • Continue for as long as spasms/rigidity lasts

Control pain

  • Morphine 2.5-10 mg IV every 4-6 hours (monitor for respiratory depression)
    Child: 0.1 mg/kg per dose
  • Paracetamol 1 g every 8 hours
    Child: 10 mg/kg every 6 hours

Prevention

  • Immunise all children against tetanus during routine childhood immunisation
  • Proper wound care and immunisation
    • Full course if patient not immunised or not fully immunised
    • Booster if fully immunised but last dose >10 years ago
    • Fully immunised who had a booster <10 years ago do not need any specific treatment
  • Prophylaxis in patients at risk as a result of contaminated wounds: give Tetanus immunoglobulin human (TIG) IM
    Child < 5 years: 75 IU
    Child 5-10 years: 125 IU
    Child > 10 years and adults: 250 IU
    Double the dose if heavy contamination or wound obtained > 24 hours.