BARCELONA — Factors that were predictive of relapse in lupus nephritis after induction therapy were persistence of proteinuria and abnormal C4 levels, and patients having received cyclophosphamide for less than 2 years, Dr. Eva Salgado reported at the annual European Congress of Rheumatology.
Considerable variability is seen in the clinical course and response to therapy in patients with systemic lupus erythematosus (SLE) who develop nephritis, and it would be useful to identify factors that are associated with relapse so that more aggressive treatment could be used from the outset, explained Dr. Salgado of Hospital 12 de Octubre, Madrid.
A study was therefore conducted that included all 128 patients diagnosed with SLE and nephritis in the rheumatology department of Dr. Salgado's hospital between 1977 and 2007.
A total of 114 of the patients were women, and more than 95% were white. Mean age at the appearance of nephritis was 30 years, and mean time from the diagnosis of SLE was 2 years.
Renal biopsy at the time of diagnosis of nephritis showed minimal changes in 2% of the patients, mesangial glomerulonephritis in 18%, focal proliferative glomerulonephritis in 12%, diffuse proliferative glomerulonephritis in 55%, and membranous glomerulonephritis in 13%.
At the time of initiation of induction therapy, 29 patients had some degree of creatinine increase, Dr. Salgado wrote in a poster session.
Induction therapies included corticosteroids alone in 23% of patients, corticosteroids plus cyclophosphamide in 65%, azathioprine in 10%, and mycophenolate mofetil in 2%. Mean duration of induction therapy was 27 months.
A total of 71% of patients showed a complete response to induction therapy, while 24% had a partial response and 5% did not respond.
After the initial response, 59% received maintenance therapy with antimalarial drugs, azathioprine, or both.
During a mean of 13 years of follow-up, 34 patients experienced renal relapse, at a mean of 51 months after the end of induction therapy.
Multivariate analysis found that relapse was independently associated with persistence of abnormal C4 levels or residual proteinuria greater than 0.5 g/day after the completion of induction therapy, and duration of cyclophosphamide therapy for less than 2 years, according to Dr. Salgado.
Factors that were not predictive of relapse included histologic findings, age at SLE or nephritis diagnosis, delay in induction therapy, use of maintenance therapy, or other clinical characteristics.
Six patients developed end-stage renal failure and 14 died.
Relapse was predictive of long term renal failure but was not associated with increased mortality in this group of patients, Dr. Salgado observed.