# Expanded Phenotypic Spectrum of Cerebral Dysgenesis, Neuropathy, Ichthyosis, and Keratoderma (CEDNIK) Syndrome: A Rare Case Featuring Supraventricular Tachycardia and Tethered Spinal Cord

## TL;DR

A rare case of CEDNIK syndrome is reported with new symptoms of heart rhythm issues and spinal cord abnormalities.

## Contribution

This case expands the known symptoms of CEDNIK syndrome by including supraventricular tachycardia and a tethered spinal cord.

## Key findings

- Supraventricular tachycardia was identified in a CEDNIK syndrome patient for the first time.
- A tethered spinal cord was observed in association with CEDNIK syndrome, a novel finding.
- The case contributes to a broader understanding of the clinical variability in CEDNIK syndrome.

## Abstract

Cerebral dysgenesis, neuropathy, ichthyosis, and keratoderma (CEDNIK) syndrome is a rare, autosomal recessive neurocutaneous disorder. It represents a progressive neurodegenerative condition caused by mutations in the synaptosome-associated protein 29 (SNAP29) gene, which encodes a member of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) family. This protein plays a critical role in intracellular membrane fusion and protein trafficking. Mutations in SNAP29 disrupt normal cellular processes, resulting in a broad spectrum of clinical manifestations, including facial dysmorphisms, microcephaly, severe developmental delay, hypotonia, ichthyosis, and peripheral neuropathy. In this report, we describe a rare case of CEDNIK syndrome featuring novel clinical findings, supraventricular tachycardia (SVT) and a tethered spinal cord, both of which have not been previously documented in association with this syndrome. These observations contribute to the expanding phenotypic spectrum of CEDNIK syndrome.