Probable chronic viral encephalitis with microglial nodules in the entire brain: a case report with necropsy.
BACKGROUND
Chronic encephalitis has rarely been seen, probably due to its viral origins, which may produce the disease in healthy or immunocompromised hosts. The etiology and pathophysiology of these types of encephalitis have not yet been clarified.


METHODS
A 63-year-old Japanese woman with underlying multiple myeloma developed chronic encephalitis with fever and progressive dementia, bilateral mild thalamic lesions on magnetic resonance imaging, and a prolonged pleocytosis, normal glucose value, and elevated interleukin-6 and interferon-gamma in the cerebrospinal fluid (CSF). The patient died of pneumonia 6 months after the onset of illness, and diffuse microglial nodules were found in the entire brain. No causative viral agents were identified by polymerase chain reaction and serological tests.


CONCLUSIONS
The patient was presumed to have suffered from chronic viral encephalitis, based on clinical findings, including CSF and cytokine changes. Microglial nodules are observed in flavivirus group encephalitides, Rickettsia infections, and cytomegalovirus encephalitis in immunocompromised hosts. The possible pathogenesis of this rare encephalitis is discussed.
Imaizumi
Toshihiro
T
First Department (Neurology) of Internal Medicine, Kurume University School of Medicine, Japan.
Nishizaka
Shinya
S
Ayabe
Mitsuyoshi
M
Shoji
Hiroshi
H
Ichiyama
Takashi
T
Sugita
Yasuo
Y
D001344:Autopsy; D001921:Brain / Q000473:pathology*; D002908:Chronic Disease; D018792:Encephalitis, Viral / Q000150:complications / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D017628:Microglia / Q000473:pathology*; D008875:Middle Aged; D009101:Multiple Myeloma / Q000150:complications