Background: An infection known to be a major cause of mild encephalitis/encephalopathy with a reversible splenial lesion (MERS). Rapidly progressive dementia is a neurological condition in which dementia progresses in a short period of time.
Case report: We report on a 78-year-old woman presenting with a rapid decline in cognitive function resulting from a scrub typhus infection. Diffusion weighted images showed a signal intensity at the splenium, and subcortical white matter of both hemispheres suggesting MERS. On the neuropsychological test, the patient showed frontal executive dysfunction.
Conclusions: This case suggests that diagnosticians should consider the possibility that a MERS patient with a rapidly cognitive decline could have a scrub typhus infection because early diagnosis of scrub typhus is very important in this aspect of the treatment.
Keywords: dementia; scrub typhus; splenial lesion.