To determine whether patients with systemic lupus erythematosus undergoing long-term peritoneal dialysis have persistent clinical and serologic remissions, the clinical courses of eight patients with end-stage renal disease in whom peritoneal dialysis was begun at Rush-Presbyterian-St. Luke's Medical Center between 1981 and 1986 were analyzed. Patients were followed for a mean of 90.1 +/- 28.8 months before dialysis and 20.8 +/- 4.7 months after the initiation of dialysis. Disease activity was quantified for each individual in terms of "flares" per year before and after the initiation of peritoneal dialysis, the means of which were 0.66 +/- 0.46 and 0.94 +/- 0.28, respectively. Comparison of these rates showed no statistical difference. Seven of the eight patients had at least one flare while receiving peritoneal dialysis, all of which required prednisone therapy (mean 31.3 mg per day). The clinical manifestations included fever, rash, myalgias, anemia, leukopenia, serositis, and cerebritis. Eighty-eight percent of these flares had associated worsening of serologic results. Prednisone was discontinued in only one patient at any time during peritoneal dialysis. This experience reveals that patients with lupus continue to show clinical and serologic disease activity and require maintenance prednisone therapy while receiving long-term peritoneal dialysis.