Scleredema in a patient with rheumatoid arthritis and monoclonal gammopathy of undetermined significance: case report

Scleredema is a rare connective tissue disorder that typically causes non-pitting induration of the posterior neck and upper back. It most often follows upper respiratory tract infections and is also linked to diabetes and monoclonal gammopathies. Association with rheumatoid arthritis is rarely reported. We present a 63-year-old male with long-standing rheumatoid arthritis who developed progressive cervical and upper back induration over 12 months. Skin biopsy revealed thickened dermal collagen bundles separated by interstitial mucin with a mild superficial perivascular lymphocytic infiltrate. Blood tests identified an immunoglobulin G-κ monoclonal component consistent with monoclonal gammopathy of undetermined significance. He received intravenous immunoglobulin, phototherapy, and thalidomide with an unsatisfactory response. This case highlights scleredema in the setting of rheumatoid arthritis and monoclonal gammopathy of undetermined significance and the ongoing challenge of selecting effective therapy.