Cerebellar ataxia following whooping cough

Bordetella pertussis (BP), the agent of whooping cough,has not been recogni zed so far as a cause of permanent cerebellar ataxia in human. We describe three patients who developed a disabling and permanent cerebellar syndrome soon after whooping cough. In two patients, diagnosis of BP infection was c onfirmed by culture of nasopharyngeal secretions. The infection occurred be tween the age of 13 and 15 years, with neurological symptoms beginning afte r a delay varying from 3 weeks to 3 months. In our three patients, the cere bellar syndrome was characterized by dysmetria of ocular saccades, scanning speech and ataxic gait. Brain MRI demonstrated a pancerebellar atrophy. Th e pathogenesis of this cerebellar degeneration is not established. Experime ntal studies have demonstrated that the cerebellum is particularly vulnerab le to lymphocytosis-promoting fatter (LPF), one of the exotoxins from BP. T he mechanism of this toxicity might be a marked increase in the cellular le vels of 3',5'cyclic guanosine monophosphate (cGMP). Since whooping cough is a bacterial exotoxin-mediated disease, this is the first report of a cereb ellar syndrome triggered by a bacterial exotoxin. (C) 1999 Elsevier Science B.V. All rights reserved.