Cortisol catabolism by lymphocytes of patients with systemic lupus erythematosus and rheumatoid arthritis

We have shown that low cortisol catabolism by lymphocytes correlates with a high sensitivity of the cells to the steroid. In the present study, we aimed to assess whether high resistance to corticosteroid treatment correlates with a high rate of cortisol metabolism by lymphocytes. Since patients with systemic lupus erythematosus (SLE) usually require high doses of corticosteroids, while patients with rheumatoid arthritis (RA) respond to relatively low doses of steroids, we compared the capability of lymphocytes of patients with SLE and RA to catabolize cortisol. The rate of cortisol catabolism obtained with the RA group was not significantly different from that obtained with the control group. The catabolism of cortisol by lymphocytes of the SLE group was significantly higher than both the control group (p < 0.05) and the RA group (p < 0.01). A significant correlation was demonstrated between the SLE disease activity index and rates of cortisol catabolism attained by lymphocytes of SLE patients (p < 0.001).