# The Importance of a Multidisciplinary Team Approach in a Rare Case of Antenatally Diagnosed Tonne-Kalscheuer Syndrome

## TL;DR

A rare X-linked disorder called Tonne-Kalscheuer syndrome was diagnosed before birth, emphasizing the need for a multidisciplinary team to provide compassionate care.

## Contribution

This case adds to the limited understanding of TOKAS's prenatal and perinatal features and underscores the importance of team-based care.

## Key findings

- TOKAS was diagnosed antenatally using whole-exome sequencing in a male neonate with multiple fetal abnormalities.
- Multidisciplinary collaboration was crucial in managing the care of the infant with a life-limiting diagnosis.
- The case contributes to the sparse literature on the prenatal presentation of TOKAS.

## Abstract

Tonne-Kalscheuer syndrome (TOKAS) is a rare X-linked neurodevelopmental disorder with very few reported cases. We describe the case of a male neonate born at 27 weeks’ gestation to a 41-year-old mother, with a diagnosis of TOKAS established antenatally through whole-exome sequencing after ultrasound revealed nuchal translucency, hydrops fetalis, structural cardiac abnormalities, and severe fetal growth restriction. The infant survived for nearly two hours after birth and was cared for and held by his parents and extended family. This case highlights the essential role of multidisciplinary collaboration, including maternal-fetal medicine, genetics, neonatology, pathology, and palliative care, in providing coordinated, compassionate, and family-centered care in the setting of a life-limiting fetal diagnosis. It also contributes to the limited literature on the prenatal presentation and perinatal course of TOKAS.