TY - JOUR T1 - Recognising the spectrum of scleromyositis: HEp-2 ANA patterns allow identification of a novel clinical subset with anti-SMN autoantibodies JF - RMD Open JO - RMD Open DO - 10.1136/rmdopen-2020-001357 VL - 6 IS - 2 SP - e001357 AU - Océane Landon-Cardinal AU - Alexandra Baril-Dionne AU - Sabrina Hoa AU - Alain Meyer AU - Valérie Leclair AU - Josiane Bourré-Tessier AU - Anne-Marie Mansour AU - Farah Zarka AU - Jean-Paul Makhzoum AU - Jessica Nehme AU - Eric Rich AU - Jean-Richard Goulet AU - Tamara Grodzicky AU - Martial Koenig AU - France Joyal AU - Isabelle Richard AU - Marie Hudson AU - Ira Targoff AU - Minoru Satoh AU - Marvin J Fritzler AU - Yves Troyanov AU - Jean-Luc Senécal Y1 - 2020/09/01 UR - http://rmdopen.bmj.com/content/6/2/e001357.abstract N2 - Objective To describe systemic sclerosis (SSc) with myopathy in patients without classic SSc-specific and SSc-overlap autoantibodies (aAbs), referred to as seronegative scleromyositis.Methods Twenty patients with seronegative scleromyositis diagnosed by expert opinion were analysed retrospectively for SSc features at myositis diagnosis and follow-up, and stratified based on HEp-2 nuclear patterns by indirect immunofluorescence (IIF) according to International Consensus of Autoantibody Patterns. Specificities were analysed by protein A−assisted immunoprecipitation. Myopathy was considered an organ involvement of SSc.Results SSc sine scleroderma was a frequent presentation (45%) at myositis diagnosis. Myositis was the most common first non-Raynaud manifestation of SSc (55%). Lower oesophagal dysmotility was present in 10 of 11 (91%) investigated patients. At follow-up, 80% of the patients met the American College of Rheumatology/EULAR SSc classification criteria. Two-thirds of patients had a positive HEp-2 IIF nuclear pattern (all with titers ≥1/320), defining three novel scleromyositis subsets. First, antinuclear antibody (ANA)-negative scleromyositis was associated with interstitial lung disease (ILD) and renal crisis. Second, a speckled pattern uncovered multiple rare SSc-specific aAbs. Third, the nuclear dots pattern was associated with aAbs to survival of motor neuron (SMN) complex and a novel scleromyositis subset characteriszed by calcinosis but infrequent ILD and renal crisis.Conclusions SSc skin involvement is often absent in early seronegative scleromyositis. ANA positivity, Raynaud phenomenon, SSc-type capillaroscopy and/or lower oesophagal dysmotility may be clues for scleromyositis. Using HEp-2 IIF patterns, three novel clinicoserological subsets of scleromyositis emerged, notably (1) ANA-negative, (2) ANA-positive with a speckled pattern and (3) ANA-positive with nuclear dots and anti-SMN aAbs. ER -