Severe Rhabdomyolysis without Systemic Involvement: A Rare Case of Idiopathic Eosinophilic Polymyositis

Polymyositis Presenting With Nontraumatic Rhabdomyolysis and Dysphagia: A Case Report

Idiopathic inflammatory myopathies (IIMs) are a rare, heterogeneous group of diseases with a characteristic clinical presentation consisting of muscle inflammation and weakness. They often present with accompanying extra-muscular findings, most notably in the skin, lungs, and joints. Inflammatory myopathies are also identified by their characteristic laboratory abnormalities, including a 10- to 50-fold increase in creatinine kinase, elevated liver enzymes, and characteristic electromyography and magnetic resonance imaging findings. Distinct autoimmune markers and clinical phenotypes have advanced our understanding of IIMs and have led to the recognition of 5 distinct entities, each with its unique pathophysiology, autoimmune markers, and clinical features. While autoimmune panels and muscle biopsies help clinicians distinguish one entity from the other, their sensitivity and specificity vary. Of the various inflammatory myopathies, polymyositis remains the most elusive. Often, the diagnosis is ultimately made by combining clinical findings and laboratory data. As our case report illustrates, clinicians must use this constellation of data to initiate treatment for suspected polymyositis despite negative autoimmune panels and negative muscle biopsy.

Successful treatment of antisynthetase syndrome presenting as rhabdomyolysis with rituximab

Rhabdomyolysis is a syndrome of muscle necrosis with subsequent release of intracellular content into the blood. There are various causes for rhabdomyolysis that include trauma, medications and rarely autoimmune conditions such as autoimmune myositis. Antisynthetase syndrome is an autoimmune condition characterized by positive antisynthetase antibody, myopathy, lung disease and arthritis. To our knowledge, rhabdomyolysis in antisynthetase syndrome has not been reported in the literature. In this report, we present a patient who presented with features of rhabdomyolysis and was diagnosed with antisynthetase syndrome. This patient was treated with systemic steroids with partial improvement, followed by rituximab, which led to significant improvement in his condition. In addition, we summarize all cases reported in the literature of inflammatory myopathy-associated rhabdomyolysis.

A Curious Case of Proximal Muscle Weakness with Eosinophilic Polymyositis

Eosinophilic polymyositis (EPM) is part of a rare disorder, eosinophilic myopathies (EM), which is a form of polymyositis characterized by the presence of eosinophils in muscle biopsy sections and occasionally blood eosinophilia. Herein, we are presenting an interesting case of eosinophilic polymyositis presenting with muscle pain with no other organ systems involved.