# Brainstem Encephalitis as an Atypical Neurologic Complication Following Kikuchi–Fujimoto Disease

## TL;DR

A patient developed brainstem encephalitis months after recovering from Kikuchi–Fujimoto disease and spontaneously recovered without treatment.

## Contribution

This case report highlights a rare neurological complication of Kikuchi–Fujimoto disease and its spontaneous resolution.

## Key findings

- A patient developed brainstem encephalitis following Kikuchi–Fujimoto disease with MRI showing a lesion in the medulla oblongata.
- The patient spontaneously recovered without immunosuppressive treatment and remained well for three years.
- Similar rare cases of encephalitis linked to Kikuchi–Fujimoto disease were identified in the literature.

## Abstract

We report an uncommon and peculiar case of a patient who developed brainstem encephalitis between three and four months after recovering from an episode of Kikuchi–Fujimoto disease (KFD). She presented acutely with oscillopsia and persistent irrepressible hiccups, for which brainstem stroke was initially suspected. Brain magnetic resonance imaging was negative for ischemic strokes but demonstrated an enhancing T2-hyperintense lesion within the area postrema of the medulla oblongata extending into the upper cervical cord. Workup for infections etiologies and demyelinating disorders of the central nervous system including neuromyelitis optica, multiple sclerosis, and antimyelin oligodendrocyte glycoprotein antibody disease, were unremarkable. Prior to the administration of immunosuppressive treatment, she spontaneously and rapidly recovered, remaining well over a 3-year period of follow-up. We reviewed prevailing scientific literature and identified similar, albeit rare, cases of encephalitis which were attributed to KFD, which we added to our discussion.