TY - JOUR T1 - Necrotising autoimmune myopathy (NAM): antibodies seem to be specific markers in aiding diagnosis JF - Journal of Neurology, Neurosurgery & Psychiatry JO - J Neurol Neurosurg Psychiatry SP - 1037 LP - 1037 DO - 10.1136/jnnp-2016-313418 VL - 87 IS - 10 AU - Marinos C Dalakas Y1 - 2016/10/01 UR - http://jnnp.bmj.com/content/87/10/1037.abstract N2 - Watanabe et al1 report on prospectively studied patients with necrotising autoimmune myopathy (NAM), diagnosed among 460 individuals with inflammatory myopathies (IM), over a 4-year period. This is the largest ever NAM cohort diagnosed with histological criteria and exclusion of genetically-defined muscular dystrophies. Among 387 patients (after excluding 16% with IBM), 30% had NAM with antibodies either against SRP (18%) or HMGCR (12%); another 13% had overlap myositis (OM), also a necrotising but perifascicular myositis, with anti-Jo-1 antibodies. Considering that antibodies are presently detected in 60–80% of NAM cases,2 this carefully studied population suggests that NAM is probably one of the commonest IM accounting, along with OM, for >50% of … ER -