Case scenario

A 38-year–old man came to the clinic with a chief complaint of jaw discomfort

and inability to open his mouth fully for 3 days. He also said he had struck

his right shin with a hammer 10 days earlier while attempting to fix his lawn

mower.

The hammer had penetrated deeply through the skin, and although the

wound hurt and bled, he had not sought medical attention. Seven days after

the original insult, he started noticing jaw discomfort and the inability to

open his mouth completely. On the 3rd day of this discomfort, his wife urged

him to seek medical attention. The patient had no history of medical or surgical

procedures, had no known allergies, and was not taking medications.

Tetanus is an acute disease manifested by skeletal muscle spasm and autonomic nervous system disturbance. It is caused by a powerful neurotoxin produced by the bacterium Clostridium tetani and is completely preventable by vaccination.

Tetanus

The Centers for Disease Control and Prevention (CDC) defines tetanus as

“the acute onset of hypertonia or…painful muscular contractions (usually of the muscles of the jaw and neck) and generalized muscle spasms without other apparent medical cause.

• C. tetani is an anaerobic, gram-positive, spore-forming rod whosespores are highly resilient and can survive readily in the environment throughout the world.

• Spores resist boiling and many disinfectants.• In addition, C. tetani spores and bacilli survive in the

intestinal systems of many animals, and fecal carriage is common.

Tetanus

• The spores or bacteria enter the body through abrasions, wounds, or (in the case of neonates) the umbilical stump.

• Once in a suitable anaerobic environment, the organisms grow, multiply, and release Tetanospasmin (tetanus toxin), an exotoxin that enters the nervous system and causes disease. Very low concentrations of this highly potent toxin can result in tetanus (minimum lethal human dose, 2.5 ng/kg).

Tetanus

Clinical Features

• Symptoms first appear from 2 days to several weeks after injury – the shorter the incubation period, the more severe the attack and the worse the prognosis.

• TRISMUS spasm of the masseter muscles, which causes difficulty in opening the mouth and in masticating; hence the name ‘lockjaw’. Lockjaw in tetanus is painless, unlike the spasm of the masseters due to dental abscess, septic throat or other causes.

Tonic rigidity spreads to involve the muscles of the face, neck and trunk.

Contraction of the frontalis and the muscles at the angles of the mouth leads to the so-called ‘Risus sardonicus’

The back is usually slightly arched (‘Opisthotonus’) and there is a board-like abdominal wall.

Clinical Features

• The back is usually slightly arched (‘opisthotonus’) and there is a board-like abdominal wall.

Clinical Features

• In the more severe cases, violent spasms lasting for a few seconds to 3–4 minutes occur spontaneously, or may be induced by stimuli such as movement or noise.

• They gradually increase in frequency and severity for about 1 week and the patient may die from exhaustion, asphyxia or aspiration pneumonia.

• Autonomic involvement may cause cardiovascular complications, such as hypertension, arrhythmias.

Clinical Features

Rarely, the only manifestation of the disease may be ‘local tetanus’ – stiffness or spasm of the muscles near the infected wound – and the prognosis is good if treatment is commenced at this stage.

Clinical Features

Investigations

The diagnosis is made on clinical grounds. It is rarely possible to isolate the infecting organism from the original locus of entry.

Management

• Identify and treat Entry wound – Prevents further release of Toxin– Metronidazole and Penicillin are the antibiotics•Antitoxin•Give as early as possible•Human Tetanus Immunoglobulin (TIG) Vs Equine Antitoxin EAT)•TIG: 3000-6000 IU Single IM inj•EAT: 10000,20000 IU Single IM inj•Intrathecal administration shown beneficial

Controlling SpasmsBenzodiazepines, IV magnesium sulfate, Propofol

Securing the airway- Patients should be nursed in calm, quiet environments because light and noise can trigger spasms- Endotrachial intubation or Tracheostomy

Cardiovascular instability- Sedation, MgSO4, Short acting Beta Blockers and inotropes

Management

• Complications arising from treatmentThrombophlebitis associated with diazepam injection, ventilator-associated pneumonia, central-line infections, and septicemia.

• Recovery from tetanus may take 4–6 weeks. Patients must be given a full primary course of immunization

Management

Tetanus Vaccination

The WHO guidelines for tetanus vaccination consist of a primary course of three doses in infancy,boosters at 4–7 and 12–15 years of age, and one booster in adulthood.

Questions?