Tetanus

Tetanus (also called lockjaw or trismus) is a serious, often fatal disease that affects the muscles and nerves.

Characterized by severe generalized muscle rigidity and spasms, tetanus is an acute illness caused by the exotoxin tetanospasmin, which is secreted by the bacterium Clostridium tetani. C. tetani, an anaerobic gram-positive rod with vegetative and sporulated forms, is present in soil and feces worldwide. Tetanospasmin, a potent neurotoxin, diffuses into the nervous system, where it causes disinhibition of the autonomic and motor nervous systems. Although the incubation period can be as short as 1 day or as long as 1 month, symptoms usually develop over 2 to 5 days approximately 1 to 2 weeks after the initial injury. A shorter incubation period portends a more severe course. Although rare in the United States, tetanus causes an estimated 800,000 deaths per year worldwide, principally as a result of neonatal tetanus.

Tetanus should be considered particularly in older patients (women may not have been vaccinated because of lack of military service), those with recent wounds (contaminated, operative, or burns), and in intravenous drug users. In some cases, no history of skin break is noted.

Causes

The bacteria that cause tetanus, Clostridium tetani, are found in soil, dust and animal feces. When they enter a deep flesh wound, spores of the bacteria may produce a powerful toxin, tetanospasmin, which acts on various areas of your nervous system. The effect on your nerves can cause muscle stiffness and spasms — the major signs of tetanus.

Symptoms

• Jaw pain or tightness
• Neck or back pain or stiffness
• Dysphagia
• Extremity pain, especially in the wounded extremity
• Cranial nerve palsies +

Unless treated, symptoms progress from pain and stiffness to rigidity and violent convulsive spasms.

Signs

• Trismus
• Tetanic spasms, especially in the face (risus sardonicus) and back muscles (opisthotonus)
• Hypersympathetic autonomic disturbances: tachycardia, labile blood pressure, hyperpyrexia, dysrhythmias

Treatment

General measures to treat the sources of the bacterial infection with antibiotics and drainage are carried out in the hospital while the patient is monitored for any signs of compromised breathing muscles. Treatment is directed toward stopping toxin production, neutralizing its effects, and controlling muscle spasms. Sedation is often given for muscle spasm, which can lead to life-threatening breathing difficulty.

Tetanus infection often requires a long period of treatment in an intensive care setting. Drugs may be used to sedate you and to paralyze your muscles, which may result in your breathing needing to be supported temporarily by a ventilator.

Prevention

Tetanus is completely preventable by active tetanus immunization. Immunization is thought to provide protection for 10 years. Studies in the army suggest that good protection persists up to 12 years after the last immunization.

Thorough cleaning of all injuries and wounds and the removal of dead or severely injured tissue (debridement), when appropriate, may reduce the risk of developing tetanus.