Brief Communication: Immune Checkpoint Inhibitor-induced Diaphragmatic Dysfunction: A Case Series.

Diaphragmatic dysfunction is a rare cause of dyspnea that can lead to hypercapnic respiratory failure. A variety of causes of diaphragmatic dysfunction have been identified, including myopathies and neuropathies, the latter of which can be further subdivided into infectious, idiopathic, demyelinating, malignant, and iatrogenic etiologies. Now, in the era of immune checkpoint inhibitors (ICIs), case reports of immune-mediated phrenic nerve palsies have been described. This diagnosis can be challenging to make, as dyspnea is a common presenting complaint and immune-mediated palsy of the phrenic nerve is a rarely described complication of ICI therapy. At Mayo Clinic, 3 patients with diaphragmatic dysfunction in the setting of ICI therapy were successfully treated without mortality. This case series describes the presentation, diagnoses, and management of these patients and their clinical outcomes.