Brachial neuritis involving the bilateral phrenic nerves.

Brachial neuritis with bilateral hemidiaphragmatic paralysis has been reported in two previous cases in the literature. We report a patient who experienced severe right shoulder discomfort three weeks prior to hospital admission which evolved to include both shoulders. Two weeks prior to admission he noticed the onset of discomfort in breathing in the supine position and shortness of breath with minor exertion. The admitting diagnoses were myocardial infarction due to significant ECG changes and idiopathic elevated bilateral hemidiaphragms. The patient had findings significant for tachypnea, dyspnea, decreased breath sounds at the bases bilaterally, impaired motion of the bilateral lung bases on inspiration and paradoxical respirations. Comprehensive medical testing and evaluation revealed bilateral elevated hemidiaphragms and vital capacity 40% of normal. Weakness of the proximal shoulder girdle and bicep musculature bilaterally was noted. Electromyography was significant for reduced recruitment pattern in the bilateral shoulder girdle musculature. Nerve conduction studies suggested bilateral phrenic neuropathy. This case is an unusual presentation of brachial neuritis affecting the bilateral shoulder girdle with phrenic nerve involvement. The differential diagnosis of acute shoulder pain associated with respiratory symptomatology should therefore include brachial neuritis.