Therapeutic plasma exchange for steroid refractory idiopathic inflammatory myopathies with interstitial lung disease

BACKGROUND: Idiopathic inflammatory myopathies (IIMs) encompass many rheumatologic diseases characterized by inflammatory muscle disease, typically unified by proximal muscle weakness. A subset of patients with IIM present with interstitial lung disease (ILD) with identifiable antibodies such as in anti-synthetase syndrome (AS) with antibodies to aminoacyl-tRNA synthetases, and clinically amyopathic dermatomyositis (CADM) with anti-melanoma differentiation-associated protein 5 (MDA5). Recent case reports demonstrate response to therapeutic plasma exchange (TPE) or column filtration plasmapheresis in IIM with ILD resistant to medical management. We present our experience with eight patients with IIM with ILD undergoing TPE at a large US-based hospital system. PATIENT CHARACTERISTICS: Eight patients with IIM with ILD were treated with TPE over the last 10 years. The therapy consisted of 5-7 one plasma volume exchanges every other day to daily. Seven of eight patients had identifiable antibodies. RESULTS: Following completion of TPE, seven of eight demonstrated improvement in pulmonary function despite lack of improvement of pulmonary function with standard therapy. CONCLUSION: In antibody-mediated, treatment refractory IIM with ILD, TPE may be a viable intervention. This is a disease for which the role of apheresis is evolving. CLINICAL TRIAL REGISTRATION: Not application.