[Development of multiple subcutaneous nodules in a patient with rheumatoid arthritis during methotrexate therapy]

A 59-year-old woman with a 14 years' history of seropositive nodular rheumatoid arthritis (RA) who developed multiple subcutaneous nodules during methotrexate therapy was reported. Weekly pulse methotrexate therapy (5-7.5 mg) was initiated in June, 1990 for exacerbation of RA. By January 1991 (total dose of methotrexate: ca 240-310 mg), marked clinical and laboratory improvements were observed. However, subcutaneous which were present prior to methotrexate administration, increased in number and size. The excised nodules showed typical histological features of rheumatoid nodules. The subcutaneous were also characterized by their presence in atypical locations such as the extensor surfaces of finger joints and toes. Recent reports which describe development of subcutaneous nodules and vasculitic lesions in RA patients following methotrexate therapy indicate different pathogenetic mechanisms might be involved in articular disease and nodular lesions.