[Acute encephalopathy following cranial irradiation of previously treated meningeal leukemia].

The sudden occurrence of an encephalopathic symptomatology within a day following commencement of radiotherapy is demonstrated by a case report of a small child suffering from CNS leukemia. Former intrathecal chemotherapy appears to be a prerequisite for this toxicity. In spite of diuretic therapy the patients condition may worsen initially, but recovery is possible within days. Patient characteristics and disease course identify a new toxicity syndrome, which is not yet familiar.