Treatment with Rituximab in Rheumatoid Pneumoconiosis: A Case Report

Background: Caplan's syndrome, also known as rheumatoid pneumoconiosis (RP), is a rare disease associating pneumoconiosis with rheumatoid arthritis (RA). This is one of the rare cases evaluating the effect of Rituximab, which was used initially for the treatment of RA, on pneumoconiosis. Case presentation: In this case report, we described a 21-year long-standing history of pneumoconiosis and its association with RA. A 67-year-old man diagnosed with pneumoconiosis presented with morning stiffness and symmetrical polyarthritis. Laboratory investigations showed high titers of rheumatoid factor (RF) and anti-citrullinated protein antibodies. The diagnosis of RA was established and the patient was put on leflunomide. Then, he was treated with Rituximab, as he did not respond to leflunomide. The patient showed marked improvement as pain and swelling decreased. More importantly, Caplan’s nodules stabilized on chest-computed tomography. Conclusion: The use of rituximab in pneumoconiosis does not alter the evolution of the pulmonary nodules. More trials are needed to establish a treatment consensus for RP.