Progressive joint damage during penicillamine therapy for rheumatoid arthritis

Progressive joint damage characterises rheumatoid arthritis despite treatment with slow-acting drugs such as penicillamine. We examined a cohort of 145 RA patients, treated with 250 or 500 mg penicillamine daily for 18 months to study progressive joint damage measured using Larsen's standard radiographs. Overall damage increased significantly over 18 months at both doses of penicillamine. Radiological changes between 6-18 months were studied in detail in 55 cases. They were divided into rapidly progressive (increases in Larsen score of more than 5) or slowly progressive (increases in Larsen score of 5 or less). Overall clinical response, visual analogue pain score, ESR, haemoglobin and platelet count were significantly lower in the slowly progressive patients; articular index and duration of morning stiffness were slightly lower; latex titre, RAHA titre, joint size and white cell count showed no differences between groups. There is an indirect relationship between progressive joint damage and some clinical and laboratory measures. The reasons underlying our failure to control progression in some cases need further definition.