The following is a summary of “Rheumatoid Vasculitis–Associated Foot Gangrene,” published in the June 2023 issue of Rheumatology by Liao et al.

Among the most severe complications of rheumatoid arthritis (RA) is rheumatoid vasculitis (RV). Venables et al. discovered that immune complexes in circulation might be implicated in the pathogenesis of RV. Rituximab (RTX) is efficacious for RV patients. In the past five years, a 41-year-old woman with a 5-year history of erosive seropositive RA was treated with methotrexate (7.5 mg/week) and hydroxychloroquine (0.2 g/day). 

Seven months of numbness and pain in the lower extremities were followed by the appearance of bruised digits that progressed to foot gangrene. The patient had no diabetes or atherosclerosis in their medical history. Electromyography revealed sensorimotor peripheral neuropathy with the lower extremities’ mixed axonal and demyelination features. Negative antineutrophilic cytoplasmic antibody. Normal levels of cryoglobulins and complement C3 were observed. Lower extremity computed tomography angiography revealed no indications of macrovascular disease. The elevated erythrocyte sedimentation rate was 37 mm/h, and the rheumatoid factor and anti-cyclic citrullinated peptide antibody titers were 105 U/mL and 375 U/mL, respectively. 

Initial administration of a high methylprednisolone dose (1 mg/kg/day) was followed by a progressive reduction to 0.5 mg/kg/day. About 6 months were spent administering cyclophosphamide intravenously at a dose of 0.6 g every two weeks. The symptoms of arthritis improved, but the foot necrosis persisted. Therefore, the patient received four 100-mg RTX infusions weekly for four weeks, totaling 400 milligrams. By week 12, the foot gangrene had been effectively controlled, and the numbness and agony in the lower extremities had subsided. In the following year, the gangrenous toe completely detached.

Source: jrheum.org/content/50/6/845