BACKGROUND

Tetanus immunization, mandatory in France before the age of 18 months, is usually well tolerated. Fever and local reaction at the site of injection are the most common side effects. We report a case of trismus associated with tetanus immunization.

METHODS

A 12-year-old boy was hospitalized for a trimus which occurred 22 h after a booster dose of tetanus polio vaccine. The spasm of masticator muscles was so severe that the patient had difficulties in elocution and feeding. A moderate fever and a hypertonia of the lower limbs were associated. The trismus resolved itself within about 5 min after diazepam intravenous infusion. After examination of the buccal cavity, a local cause was discarded. The outcome was favorable and the clinical status of the boy was still normal six months later.

CONCLUSIONS

Although no similar cases have been published, 13 other comparable adverse events associated with four vaccines containing tetanus toxoid were reported to the manufacturer within a period of 12 years. During the same period, more than 66 millions doses of vaccines containing tetanus toxoid were distributed. Trisms appeared to be more likely reported in adults after booster doses. Onset of the symptoms was between a few hours to 15 days. Outcome was always favorable.

CONCLUSIONS

Although trimus associated to tetanus toxoid immunization is rare and remains unexplained, physicians should be aware of this adverse event.