Pertussis encephalopathy in an adult: case report and review.

A 39-year-old man developed paroxysmal cough, occasional vomiting after cough, and subconjunctival hemorrhage. His illness was complicated by episodes of seizure, with clonic movements of the arms and legs, brief loss of consciousness, and confusion. The episodes were triggered by mild, unremarkable coughing paroxysms. A diagnosis of pertussis was confirmed serologically by measurement of IgG, IgA, and IgM antibodies to pertussis toxin and filamentous hemagglutinin. Serologic studies confirmed the presence of Bordetella pertussis infection in the patient's 10-year-old daughter and suggested that his wife was infected as well. This case report illustrates the occurrence of typical pertussis with serious complications in an adult. Further research is required to determine the scope of this problem and the need for a program of adult immunization against pertussis.