Acute encephalomyelitis during an outbreak of enterovirus type 71 infection in Taiwan: Report of an autopsy case with pathologic, immunofluorescence,and molecular studies

We report a fatal case of enterovirus type 71 (EV 71) infection in an 8-yea r-old girl during a summer outbreak of hand, foot, and mouth disease in 199 8 in Taiwan. The clinical course was rapidly progressive, with manifestatio ns of hand, foot, and mouth disease, aseptic meningitis, encephalomyelitis, and pulmonary edema The patient died 24 hours after admission. Postmortem study revealed extensive inflammation in the meninges and central nervous s ystem and marked pulmonary edema with focal hemorrhage. Brain stem and spin al cord were most severely involved. The inflammatory infiltrates consisted largely of neutrophils involving primarily the gray matter with perivascul ar lymphocytic cuffing, and neuronophagia. The lungs and heart showed no ev idence of inflammation. EV 71 was isolated from the fresh brain tissues and identified by immuno-fluorescence method with type-specific EV 71 monoclon al antibody. It was also confirmed by neutralization test and reverse-trans criptase polymerase chain reaction with sequence analysis. The present case was the first example in which EV 71 was demonstrated to be the causative agent of fatal encephalomyelitis during its epidemic in Taiwan.