Acute measles encephalitis in children with immunosuppression.

Four cases of encephalitis occurring in children treated for lymphatic malignancies by immunosuppressive drugs are reported. Measles virus was isolated from the brain in one case and identified immunologically in another. Nucleocapsids identical to those seen in subacute sclerosing panencephalitis were demonstrated in three cases. Severe immunosuppression was evidenced in two patients by failure of rosette formation and low phytohemagglutinin tests. Pathologically, the inflammatory reaction was absent in one brain and moderate in two. Clinically, epilepsia partialis continua was a prominent feature in three patients. A history of measles or of contact was elicited in three cases, five weeks to three months before onset. All cases ran an acute fatal course. Measles virus can behave as an opportunistic invader of the central nervous system in children and the diagnosis of measles encephalitis should be considered in immunosuppressed patients.