Statin-Associated Autoimmune Myopathy

Abstract

Statin-associated necrotizing myopathy is a symmetric proximal muscle weakness associated with extreme elevations of CK. It is common in males and can occur after months of statin use. It is associated with necrosis on muscle biopsy and the presence of anti-HMG-CoA reductase antibodies. It usually requires discontinuation and immune suppression for resolution. Rechallenge with statin is unsuccessful in most cases.

A Rapidly Progressive Case of Statin-induced Necrotizing Autoimmune Myopathy

“…Often times, the presenting symptoms mimicked other more common autoimmune myopathies such as polymyositis [11]. A systematic literature review of 100 SINAM cases by Nazir et al found that the mean duration of statin use prior to the onset of myopathy symptoms was 40.48 months, which is much longer than our patient's presentation after only one month of use [12]. Treatment outcomes for SINAM patients were favorable, with 91% of patients having a complete resolution of symptoms.…”

Necrotizing Autoimmune Myopathy: A Rare Variant of Idiopathic Inflammatory Myopathies

“…As compared to statin-associated myopathy where CK is in hundreds, CK in NAM is usually in thousands. 7 EMG studies show abnormalities consistent with the irritable myopathic process. Muscle biopsy remains the gold standard for diagnosis, and histopathologic findings show presence of necrotic and regenerative myofibers.…”

“…3 Affected patients have been advised against the use of statin in future life as continuation has been found to be associated with worse outcomes. 7 Moreover no significant differences in disease severity, outcomes, and response to therapy have been found among the different etiologic groups. Overall, the mortality in patients with IIM remains 2- to 3-fold higher than the general population, with cardiac, lung complications, cancer, and lung infections being the most common causes of deaths.…”

A Rare Case of Statin-induced Immune-mediated Necrotizing Myopathy

“…Muscle biopsy usually shows necrosis with the regeneration of muscle fibers and scarce inflammation, mainly composed of macrophages. The serologic diagnosis is by testing for anti-HMGCR antibodies [2,5,6,8].…”