Early rheumatoid arthritis in a patient with Sjögren's syndrome and pulmonary nodular amyloidosis: clinical implication of early limited use of infliximab

Abstract

Infliximab, an anti-tumor necrosis factor α antibody, is among the most effective therapies for rheumatoid arthritis (RA). In this study, we report a patient with early RA of 6 months who has Sjögren's syndrome and pulmonary nodular lesions concomitantly. The patient did not respond to methotrexate (MTX, 6^Smg per week) for 3 months. When introduction of infliximab therapy is considered, we need to exclude the possibility of pulmonary granulomatous infection and malignancy. With the use of computed tomography-guided percutaneous needle biopsy and subsequent histological examinations, this case was rapidly and confidently diagnosed as localized pulmonary nodular amyloidosis. Immunochemical staining showed light chain type nodular amyloidosis by a deposition of immunoglobulin κ light chains, which is a rare condition in a patient with Sjögren's syndrome. We started combination therapy of infliximab (200^Smg per infusion) and MTX (6^Smg per week). Because of severe systemic eruption, this therapy was stopped halfway through the third infusion of infliximab, and MTX monotherapy was continued. Despite the withdrawal of infliximab therapy, the C-reactive protein values were decreased to an undetectable level at week 14, and the disease activity score for 28 joints was 3.1 at week 22. Clinical remission has been maintained more than 14 months with MTX alone. Infliximab has been used only for patients with recalcitrant RA, because the cost of its lifelong use would be an economic burden in most cases. An optimal and affordable strategy for the treatment of early RA should be developed. Our findings may support the idea that the combination therapy of infliximab and MTX for early RA alters the course of the disease.

Key words:

• Amyloidosis
• CT-guided lung biopsy
• Infliximab
• Methotrexate
• Rheumatoid arthritis
• Sjögren's syndrome