Clinical characteristics of the Pisa syndrome

The Pisa syndrome is not yet well characterized, although there have been increasing reports on its prevalence and the clinical features of drug‐induced dystonia. In this report, we present 20 cases of the Pisa syndrome and discuss the clinical symptoms compared with those of classical types of drug‐induced dystonia. The Pisa syndrome may occur not only as a subtype of acute dystonia but also as a subtype of tardive dystonia. Abnormal findings on brain CT were noted in both acute and tardive types of the Pisa syndrome, indicating that, like tardive dystonia, the Pisa syndrome may be associated with cerebral lesions. Young female patients were susceptible to both acute and tardive types of the Pisa syndrome, but the prevalence of both types of dystonia was inconsistent in these patients. Thus, it seems likely that very complicated pathophysiological changes in the brain are involved in the development of the Pisa syndrome.