# Partial Rhombencephalosynapsis Presenting in an Adult with Cerebello-Trigeminal-Dermal Dysplasia

## TL;DR

This paper reports a rare case of a brain and skin disorder diagnosed in an adult for the first time, highlighting that it can present with seizures and mild symptoms.

## Contribution

The paper presents a rare adult-onset case of GLHS, expanding the known age range for diagnosis.

## Key findings

- GLHS can be diagnosed in adulthood, even with minimal symptoms.
- New-onset seizures in adults can be the first sign of GLHS.
- MRI findings confirmed partial cerebellar fusion consistent with RES in the adult patient.

## Abstract

•Gomez-Lopez-Hernandez syndrome (GLHS) patients may be paucisymptomatic.•GLHS may be diagnosed in adulthood.•New-onset adulthood seizures may be the first presenting symptom of GLHS recognized.•Clinically GLHS is defined by: partial alopecia, truncal ataxia, muscular hypotonia.•GLHS exhibits: cerebellar fusion, vermian immaturity, dentate medialization.

Gomez-Lopez-Hernandez syndrome (GLHS) patients may be paucisymptomatic.

GLHS may be diagnosed in adulthood.

New-onset adulthood seizures may be the first presenting symptom of GLHS recognized.

Clinically GLHS is defined by: partial alopecia, truncal ataxia, muscular hypotonia.

GLHS exhibits: cerebellar fusion, vermian immaturity, dentate medialization.

Gomez-Lopez-Hernandez syndrome (GLHS), also known as cerebello-trigeminal-dermal dysplasia, is a neurocutaneous disorder typically presenting in childhood. GLHS is characterized by rhombencephalosynapsis (RES) and partial alopecia, with or without trigeminal anesthesia. We describe a rare case of GLHS in a paucisymptomatic adult who presented with new-onset seizure-like activity. Magnetic resonance imaging revealed partial midline fusion of the cerebellar hemispheres, incomplete development of vermis, and slight medialization of the dentate nuclei: all consistent with the diagnosis of RES. Radiographic evidence combined with partial alopecia, truncal ataxia, and muscular hypotonia are suggestive GLHS diagnosis. Our report not only highlights the importance of maintaining GLHS on the differential for new-onset seizure-like activity, but also demonstrates how patients with GLHS may be minimally symptomatic and diagnosed in adulthood.

The Gomez-Lopez-Hernandez syndrome (GLHS), or cerebellotrigeminal-dermal dysplasia, is a rare condition that affects both the nervous system and the skin. It involves abnormal development of the brain, partial alopecia [thinning of hair], and loss of sensation in the face. One specific brain malformation, called rhombencephalosynapsis (RES), results from abnormal formation of the cerebellum and is seen in GHLS.Both RES and GLHS present early in childhood, and cases presenting later in life are exceptionally rare. Here we describe a young adult with RES and GLHS whose normal development and mild clumsiness eluded recognition by doctors until early adulthood when she presented with a single seizure.