Background: Cryptogenic organizing pneumonia (COP) is an interstitial lung disease, with causes including anti-CD20 antibodies. Ocrelizumab is a humanized monoclonal antibody against CD20 approved for use in relapsing-remitting or primary progressive multiple sclerosis (MS), with no conclusive data regarding pulmonary toxicity.
Cases: We describe two cases of COP associated with ocrelizumab use in multiple sclerosis patients.
Conclusions: We suggest considering COP whenever respiratory symptoms arise in MS patients receiving ocrelizumab therapy. COP diagnosis requires clinical and radiological exclusion of alternative diagnoses such as opportunistic infections, autoimmunity, drugs, and neoplasms. Appropriate steroid therapy has an excellent clinical response rate.
Keywords: CD20; Ocrelizumab; Organizing pneumonia; drug-induced organizing pneumonia; multiple sclerosis.