Motor neurone disease presenting as polycythaemia.

Motor neurone disease (MND) is a chronic, progressive and currently incurable neurodegenerative disorder. This case report discusses an instance of MND presenting initially as polycythaemia, caused via insidious respiratory failure through ventilatory insufficiency. This case aims to improve clinicians' awareness of this atypical presentation and highlights the need for a high index of suspicion of respiratory failure in any patient with polycythaemia. Finally it demonstrates an improvement in quality of life associated with the use of non-invasive ventilation (NIV) in a patient with MND.