Respiratory Failure Secondary to Diaphragmatic Paralysis from Acute Exacerbation of Dermatomyositis.

Dermatomyositis (DM) is an idiopathic inflammatory disorder that presents with proximal muscle weakness and typical DM skin changes. DM can involve other organs such as the lung, esophagus, and heart. Diaphragmatic muscle paralysis is an unrecognized clinical presentation of acute DM exacerbation. A 58-year-old man with a history of DM presented to the hospital after sustaining a cardiorespiratory arrest. Before arrest, he had been suffering from progressive dyspnea and muscle weakness. Immunosuppressive therapy of tacrolimus for DM was recently discontinued due to renal toxicity. Bedside ultrasound of the diaphragm while intubated revealed evidence of bilateral diaphragmatic paralysis. After extubation, supine and upright pulmonary function tests (PFT) and sniff test results strengthened the diagnosis of diaphragmatic paralysis. The patient was worked up for an acute DM exacerbation as the likely etiology of the severe diaphragmatic muscle weakness (diaphragmatic paralysis) and ventilatory failure. Skin and muscle biopsy confirmed the diagnosis of active DM. The patient was treated with high dose steroids and mycophenolate mofetil, following which he soon recovered.