Long-term follow-up of metatropic dysplasia caused by novel mutations in the TRPV4 gene: Case report and literature review.

RATIONALE

To observe the natural history of the disease and the radiographic evolution of growth and development in patients with metatropic dysplasia (MD) and to complement the spectrum of mutations in the transient receptor potential vanilloid 4 (TRPV4) gene and the spectrum of MD phenotypes.

PATIENT CONCERNS

We report a patient with MD caused by a novel missense mutation in TRPV4, who possessed a mixed phenotype of both abnormal skeletal development and peripheral neuropathy. From 3 months to the age of 7 years, we observed the patient's natural history and the imaging evolution of the patient's growth and development.

DIAGNOSIS

The diagnosis of MD based on growth and developmental history, clinical presentation, imaging and mutation analysis of the TRPV4 gene.

INTERVENTIONS

She underwent posterior spinal osteotomy (T10, vertebral column resection), lateral kyphosis correction, internal fixation (T6-L3), and implant fusion. Surgical intervention can effectively delay the course of the disease.

OUTCOMES

Sequencing analysis and family validation of the patient's whole exon gene confirmed for the first time that the mutation in exon 11 of the TRPV4 gene was a heterozygous missense mutation (c.1811T > A) resulting in the mutation of isoleucine at position 604 to asparagine (p. I604N).

LESSONS

This study complements the spectrum of mutations in the TRPV4 gene and the spectrum of MD phenotypes and provides a reference for prenatal diagnosis, genetic counseling, mechanistic studies, and development of symptomatic treatment for this type of disease.