[Meningoencephalitis associated with polyradiculoneuropathy with increased HSV IgG antibody--report of three cases]

We report three patients presented with meningoencephalitis associated with polyradiculoneuropathy with increased HSV IgG antibody titer. The first patient was a 27-year-old woman with meningoencephalitis who developed status epilepticus. The CSF showed pleocytosis and increase in HSV IgG antibody titer. Herpes encephalitis was suspected, and she was treated with acyclovir. The symptoms of meningoencephalitis improved, but she developed flaccid tetraplegia. The NCV study was compatible with polyradiculoneuropathy. About two months later from the onset, muscle atrophy appeared in her all limbs. The second patient was a 23-year-old woman with meningoencephalitis, which was followed by ascending motor paralysis. The CSF showed pleocytosis and increase in HSV IgG antibody titer. The symptoms of meningoencephalitis improved by administration of acyclovir, but paralysis didn't improve. About two months later from the onset, muscle atrophy of all limbs appeared. The NCV study was compatible with polyradiculoneuropathy. The third patient was a 43-year-old man presenting somnolence, neck stiffness and ascending motor paralysis developing into flaccid tetraplegia. The CSF showed pleocytosis and increase in HSV IgG antibody titer. Somnolence and neck stiffness improved by administration of acyclovir but tetraplegia didn't improve. The NCV study was compatible with polyradiculoneuropathy. Immuno-absorption therapy and administration of prednisolone were performed. Meningoencephalitis associated with increased HSV IgG antibody titer is rare. Auto-allergic process which is initiated by HSV infection may be involved in the pathogenesis of polyradiculoneuropathy in these patients.