# Herpes simplex virus type 2 implicated in a case of acute disseminated encephalomyelitis

## TL;DR

A rare case links herpes simplex virus type 2 to acute disseminated encephalomyelitis, a neurological disorder.

## Contribution

This is the first reported case of ADEM associated with HSV-2, expanding the known viral triggers.

## Key findings

- ADEM was diagnosed in a patient with HSV-2 confirmed via PCR.
- The patient showed neurological improvement after treatment with aciclovir and dexamethasone.
- Neurological sequelae remained despite rehabilitation.

## Abstract

Introduction. Acute disseminated encephalomyelitis (ADEM) is a well-described neurological disorder that follows acute infection, vaccination and organ transplantation. It is characterized by sudden and widespread areas of inflammation in the central nervous system. Previous case reports have described ADEM with evidence of either recent or current herpes simplex virus type 1 infection. However, here, we report a rare, to our knowledge never before documented, case of ADEM associated with herpes simplex virus type 2 (HSV-2).

Case report. A 20-year-old man presented with weakness and sensory disturbance to the lower limbs, which had gradually progressed over the preceding 7 days, with associated fever, urinary retention and bowel incontinence. Magnetic resonance imaging was in keeping with a diagnosis of ADEM with mainly spinal involvement. Lumbar puncture revealed lymphocytic pleocytosis with elevated protein, and PCR was strongly positive for HSV-2. He was treated with aciclovir and dexamethasone, along with broad-spectrum antibiotics until negative bacterial and mycobacterial culture results were obtained. His functional status improved over the following months, but, despite prolonged rehabilitation, neurological sequelae remain.

Conclusion. HSV-2 may be considered a possible aetiological agent in cases of ADEM.