Rituximab treatment in a case of anti- synthetase syndrome with severe interstitial lung disease and acute respiratory failure

We present a case of severe interstitial pneumonitis, mild polyarthritis and polymyositis, and Raynaud's syndrome with the presence of anti-Jo-1 antibodies, which had been diag- nosed as anti-synthetase syndrome. The presence, however, of anti-Ro/SSA antibodies led us to understand that we were dealing here with a more severe form of interstitial lung dis- ease. The patient was treated for acute respiratory failure but he showed resistance to glucocorticoids and cyclosporine. Thus, he was treated with infusions of anti-CD20 therapy (rituximab): his clinical conditions improved very rapidly and a significant decrease in the activity of pulmonary disease was detected using high-resolution computerized tomogra- phy (HRCT) of the thorax and pulmonary function tests.