D-penicillamine-induced increase in intracellular glutathione correlating to clinical response in rheumatoid arthritis.

Measurement of glutathione (GSH) in consecutive blood samples from patients with rheumatoid arthritis (RA) revealed, in good responders to D-penicillamine, a 20% to 35% increase in erythrocyte-GSH (E-GSH) levels after 2 to 8 wk of treatment. Usually this rise predicted a clinical response some wk later. Nonresponders to D-penicillamine who did not show an increase in E-GSH could be converted to responders by receiving L-cysteine. E-GSH rose--prior to the clinical response--by up to 50% of pretreatment values. In RA patients with spontaneous changes in disease activity, E-GSH tended to decrease during relapses and increase before remissions.