Penicillamine-induced proteinuria: risk factors.

Twenty-six of 300 patients (9%) with rheumatoid arthritis (RA) developed penicillamine-induced proteinuria. The mean daily dose and duration of therapy at onset of proteinuria were 591 mg and 9 months, respectively, while the mean duration of proteinuria was 5.5 months. However, six patients developed proteinuria at 250 mg/d and six after 9 months of therapy. Twelve patients were successfully either restarted (five) or maintained (seven) on penicillamine with resolution of proteinuria. No permanent renal impairment occurred. Positive risk factors included the presence of HLA-B8 and DR3 and prior gold-induced proteinuria. Patients with prior gold-induced proteinuria should be observed more carefully, but tissue typing is not recommended as proteinuria is reversible. Furthermore, penicillamine can be restarted or maintained in these patients if the RA has responded favorably to the drug.