# Reduced unilateral sweating caused by varicella zoster virus infection: a case report

## TL;DR

A 34-year-old woman developed reduced sweating on one side of her body due to a rare complication of varicella zoster virus infection.

## Contribution

This case report highlights a rare neurological complication of VZV involving autonomic nerve damage and unilateral sweating reduction.

## Key findings

- Herpes zoster caused unilateral sweating reduction due to autonomic nervous system damage.
- VZV reactivation in autonomic ganglia was identified as the likely cause of the patient's symptoms.
- Electromyographic testing confirmed left sympathetic nerve damage.

## Abstract

Herpes zoster is an infectious skin disease caused by the reactivation of the varicella zoster virus (VZV), which has been latent in the posterior root ganglia of the spinal cord or cranial ganglia for an extended period. Neurological complications caused by herpes zoster include aseptic meningitis, white matter disease, peripheral motor neuropathy, and Guillain-Barré syndrome. However, reduced unilateral sweating caused by the VZV is very rare.

This article reports the case of a 34-year-old woman who was admitted to our hospital with sore throat, dizziness, and reduced sweating on the left side of her body. Physical examination found herpes lesions on the left upper lip and left external ear canal (scabbed) and reduced sweating on the left side of the body. Head magnetic resonance imaging (MRI) with contrast showed no abnormalities. After a lumbar puncture, the patient was diagnosed with viral meningitis by VZV infection. The electromyographic skin sympathetic reflex indicated damage to the left sympathetic nerve.

Secondary unilateral sweating reduction is a rare neurological complication of herpes zoster, caused by damage to the autonomic nervous system. Literature review and comprehensive examination indicated that the reduced unilateral sweating was due to the activation of latent herpes zoster virus in the autonomic ganglia which has damaged the autonomic nervous system. For patients who exhibit acute hemibody sweat reduction, doctors should consider the possibility of secondary autonomic nervous system damage caused by herpes zoster.

The online version contains supplementary material available at 10.1186/s12883-024-03770-5.