OTTAWA—Patients with lupus nephritis can make good candidates for renal transplantation if their disease is quiescent for at least one year prior to surgery, according to research findings presented at the 2013 annual meeting of the Canadian Rheumatology Association.
Investigators reviewed outcomes from adults who had attended a lupus clinic at the Toronto Western Hospital in Toronto, Ontario, from 1970 to 2012. Among the 1,645 lupus patients treated in that interval, 25 had nephritis and underwent kidney transplantation. Most of these patients were white (40%) and African Canadian (28%). The remaining patients were Asian or members of other ethnic groups. None of them had any clinical evidence of lupus in the year before transplantation.
Two of the patients had a completely non-functional kidney post-transplant. Another four had graft failure, one within five years of transplant surgery and the remaining three after a longer period, with an average time to graft failure of 5.75 years. Of the 19 (76%) patients with graft survival, the graft survived at least five years in eight patients, with a mean graft survival among these eight patients of 5.7 years.
The four patients with graft failure and 19 with graft survival had roughly similar characteristics, except that the average age in the graft-survival group was higher (40 vs. 29.8 years). Significantly more whites and African-Canadians had graft survival than graft failure, at seven and one, and six and one, respectively.
In addition, the average time between lupus diagnosis and transplant was 15.5 year in the graft-survival group and 4.5 years in the graft-failure group. The respective average durations of dialysis prior to transplant were 5.8 and 3.9 years.
Three of the individuals in the graft-survival group died an average of 5.6 years post-transplant. The cause of death was not related to renal disease in two patients and unknown in the third. Another patient was lost to follow-up. In the graft-failure group, three patients died an average of six years post-transplant, and all the deaths were related to renal disease. The remaining patient is still living.
One (25%) of four patients in the graft-failure group had positive lupus serology a year before transplantation compared with nine (47%) of 19 patients in the graft-survival group. At one year post-transplant, the proportion of patients with lupus serology in the graft-failure group rose to 66%, while it fell to 42% in the other group.
“I presume that older patients had quiescent lupus disease activity for a longer period compared to the other patients, and it is possible that the severity of lupus disease activity tends to ameliorate [or] weaken years after the diagnosis of lupus,” said lead investigator Zahi Touma, MD, PhD, of the University of Toronto Lupus Clinic at the Toronto Western Hospital, in explaining the results.
In another poster presented at the rheumatology meeting, Dr. Touma and three other co-investigators analyzed the timeframe for either partial (at least 50% decrease from baseline in proteinuria) or complete, recovery from proteinuria in lupus nephritis patients. They determined that partial or complete recovery from proteinuria may be a better end point in clinical studies of this patient population because it tracks parallel to complete response but happens somewhat more quickly, which is an advantage in studies that do not last for decades.