IDIOPATHIC PHRENIC NEUROPATHIES: A CASE SERIES AND REVIEW OF THE LITERATURE

Introduction: Phrenic neuropathies (PNs) are a major cause of dyspnea, orthopnea, and hypercapnic respiratory failure. The aim of the study was to obtain diagnostic findings, assess therapeutic options, and review outcomes in PN patients. Methods: From 2004 to 2013, patients with PN referred to the author's institution were studied using clinical, pulmonary function, and electrodiagnostic tests. A PubMed search of published PN reports was also done. Unilateral PN (UPN) and bilateral PN (BPN) patients were compared. Results: The analysis consisted of 10 UPN and 9 BPN patients seen by the author, plus previous reports of 18 UPN and 40 BPN patients. BPN patients were older (in the author's series) and were more often hypertensive. They reported pain less often, dyspnea and orthopnea more often, and had worse results on pulmonary function tests than UPN patients. Conclusions: UPN and BPN are probably 2 variants of the same, immune-mediated focal neuropathy. Electrodiagnosis is a valuable confirmatory test for PN.