The first reported familial case of statin-induced immune-mediated necrotizing myopathy associated with anti-hydroxy-3-methylglutaryl-CoA reductase autoantibodies and HLA DRB1*11:01.

Immune-mediated necrotizing myopathy (IMNM) is a rare type of auto-immune myositis, characterized by symmetric muscle pain, proximal weakness, elevated serum CK levels and pathologic findings of necrotized muscle fibers. IMNM may be seronegative, associated with anti-signal recognition particle (SRP) antibodies or anti-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) antibodies, the last widely related with statin use. This last entity affects only 2 to 3 of 100,000 patients under statins. Recently, patients carrying the class II human leukocyte antigen (HLA) DRB1*11:01 were identified to be more at risk to present IMNM with anti-HMGCR antibodies. We describe the case of a daughter and father diagnosed with HMGCR-IMNM and both carrying HLA DRB1*11:01. To our knowledge, it is the first familial case reported in the literature.