Stridor: a rare presentation of motor neuron disease

Abstract

A 74-year-old farmer presented to the emergency department with a subacute history of progressive dyspnoea, wheeze and dysphonia. He was treated for an exacerbation of asthma with poor response to pharmacological therapy. Investigation of dysphonia via laryngoscopy identified a bilateral vocal cord palsy. Subsequently, the patient developed an episode of life-threatening stridor and hypercapnic respiratory failure requiring an emergency tracheostomy. Neurology input identified evidence of widespread muscle fasciculations on clinical examination. MRI of the brain and cervical spine were unremarkable. Electromyogram testing identified changes of acute denervation in several limbs consistent with a diagnosis of motor neuron disease (MND). Bilateral vocal cord palsy has been rarely reported in the literature as the heralding symptom resulting in the diagnosis of MND. In patients with a subacute onset of dysphonia, dyspnoea and stridor, MND should be a differential diagnosis.