Quick response to rituximab in a patient with Ro52-Jo1 complex-associated antisynthetase syndrome debuting with rapidly progressive interstitial lung disease and diffuse alveolar haemorrhage

Antisynthetase syndrome (AAS) is an inflammatory myopathy that may debut with interstitial lung disease (ILD). A few studies show cases in which patients with high concentrations of anti-Ro52 in patients with ILD might achieve a better response if treated with rituximab than other patients with ILD and Ro-52 whose levels are lower. We present a patient with lung involvement as the first and unique manifestation of AAS with anti-Jo and anti-Ro52-positive antibodies. The ILD was rapid and progressive and led him into the intensive care unit in a matter of days, despite several immunosuppressive treatments. As soon as the patient received this treatment, he experienced an improvement. We therefore suggest the prompt determination of anti-Ro52 antibody concentrations in this subgroup of patients, which would offer a therapeutic approach based first on rituximab over other immunosuppressive treatments.