Une paralysie diaphragmatique révélatrice d'un syndrome de Parsonage-Turner

We report the case of a 49-years-old patient who presented to the accident and emergency department with sudden onset dyspnea associated with acute shoulder pain. He was breathless at rest with supine hypoxemia. He had an amyotrophic left shoulder with localized paresis of the shoulder. Both hemi-diaphragms were elevated on chest X-rays. Pulmonary function tests showed a restrictive pattern and both phrenic nerve conduction velocities were decreased. At night, alveolar hypoventilation was evidenced by elevated mean capnography (PtcCO2: 57 mmHg). Neuralgic amyotrophy, Parsonage-Turner syndrome was the final diagnosis. This syndrome is a brachial plexus neuritis with a predilection for the suprascapular and axillary nerves. Phrenic nerve involvement is rare but where present can be the most prominent clinical feature as in our case report.