Dr Emma Goodwin
Monash Health


Title: Relapsed Statin Induced Myotoxicity

Authors: E Goodwin1, FYX Lai1, H Harianto1

1. Department of Geriatric Medicine, Kingston Centre, Melbourne, Victoria, Australia

Abstract Text: 

Clinical Record
A 60 year-old male presented with proximal weakness and generalised myalgia. He had ceased rosuvastatin (10mg daily) two months prior, following an episode of statin induced myopathy and rhabdomyolysis. Laboratory findings on admission and from the previous episode are described in Table 1. Muscle biopsy of quadriceps showed scattered atrophic fibres, no necrosis or degeneration. Musculoskeletal magnetic resonance imaging was suggestive of a myositis, most prominently involving the left gluteal muscles (Figure 1). Anti-hydroxymethylglutaryl-coenzyme A reductase (Anti-HMGCR) antibody was not elevated. The patient received prednisolone 25mg daily for one week and benefited from a period of rehabilitation. Creatine kinase (CK) normalised to 233 U/L at two weeks and continued to decrease to 52U/L following the cessation of prednisolone. 

Statin-induced myopathy can be classified into toxin and autoimmune forms. Patients generally recover spontaneously from statin-induced myotoxicity following statin cessation1. Recently recognised, statin-induced autoimmune myopathy is characterised by muscle-cell necrosis on biopsy, autoantibodies against HMGCR, weakness, and a raised CK which persists after statin discontinuation2. The clinical course of our case was initially suggestive of statin-induced autoimmune myopathy. However, muscle biopsy did not demonstrate necrosis, anti-HMGCR was negative, and resolution continued following cessation of immunosuppression. This case illustrates statin-induced myotoxicity which progressed two months following statin discontinuation. To our knowledge, this is the first report of relapsed statin-induced myotoxicity. Statins are widely used and hence physicians should be aware of the possible adverse effects and to consider appropriate investigations to differentiate potential diagnoses. We present this case to highlight the possibility of statin-induced myopathy following statin cessation. 

1. Babu, S, Li Y. (2015). Statin induced necrotizing autoimmune myopathy. J Neurool Sci, 351(1):13-17.
2. Mammen, AL. (2016). Statin-Associated Autoimmune myopathy. N Engl J Med, 374: 664-9.