An Insightful Observation Leading to a Late Diagnosis of Spinal Muscular Atrophy: A Case Report

TL;DR

A 47-year-old woman was diagnosed with spinal muscular atrophy through genetic testing after years of undiagnosed muscle weakness.

Contribution

This case emphasizes the importance of early genetic testing for accurate diagnosis and management of SMA.

Findings

A pathogenic deletion in exon 8 of the SMN1 gene was identified in a late-diagnosed SMA patient.

The case underscores the need for timely genetic evaluation in undiagnosed neuromuscular disorders.

Late diagnosis of SMA can lead to prolonged morbidity without appropriate intervention.

Abstract

Spinal muscular atrophy (SMA) is a rare autosomal recessive neuromuscular disorder characterized by the loss of motor neurons in the spinal cord that results in progressive muscle weakness and atrophy. Most often, the gene involved in this disorder is the survival motor neuron (SMN1) gene, located on the telomeric regions of chromosome 5q13. This gene is involved in the processing of pre-mRNA required for the formation of dendrites and axons. Here we present the case of a 47-year-old female with an extensive past medical history of progressive muscle weakness who, after numerous specialist evaluations, was sent for germline mutation panel sequencing and analysis and was incidentally found to have a pathogenic heterozygous deletion encompassing the exon 8 region of the SMN1 gene. This case report aims to highlight the importance of timely identification and management for individuals who present with early clinical signs of the disease to reduce the morbidity and mortality associated with it.