SAT0215 Clinical presentation, treatment and outcome of membranous nephropathy in SLE: A comparison with proliferative lupus glomerulonephritis in 141 patients

• Published in: Annals of the rheumatic diseases Vol. 71; no. Suppl 3; pp. 544 - 545
• Main Authors: Mok, C.C., Ho, L.Y., Yu, K.L., To, C.H.
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and European League Against Rheumatism 01.06.2013; BMJ Publishing Group LTD
• ISSN: 0003-4967; 1468-2060
• DOI: 10.1136/annrheumdis-2012-eular.3162

Objectives To study the presentation and outcome of membranous nephropathy in SLE in comparison with proliferative lupus glomerulonephritis. Methods Patients with biopsy firmed active lupus nephritis who were recruited in a randomized trial of mycophenolate mofetil (MMF) and tacrolimus (Tac) from 2005 to 2011 were studied. Participants were divided into 3 groups according to renal histology: group I (pure membranous lupus Gn:RPS/ISN class V); group 2 (mixed membranous/proliferative Gn: V+III or IVS/IVG) and group 3 (proliferative lupus Gn:IVS/IVG). The clinical presentation, treatment response, outcome were compared. Results 141 patients were studied (92%women; age 35.2±12.8 years, SLE duration 49.3±62 months). There were 25 (18%), 31 (22%) and 85 (60%) patients in group 1, 2 and 3, respectively. At presentation, group 1/2 patients had significantly higher hemoglobin (11.3±1.8vs9.9±1.7g/dL), creatinine clearance (CrCl) (90.0±31vs69.7±27ml/min), complement C3 level (0.62±0.27vs0.42±0.16g/L) but lower serum Cr (70.8±25vs91.5±33umol/L) and anti-dsDNA titer (166±116vs234±89IU/ml) than group 3 patients (p<0.001). 18 (32%) patients in group 1/2 had normal range C3 or anti-dsDNA, compared to 3 (4%) patients in group 3 (p<0.001). Nephrotic syndrome was more common in group 1/2 than group 3 patients (46% vs 32%; p=0.08) but the difference was no significant. Blood pressure and serum albumin level was similar among the 3 groups of patients. The SLE disease activity index (SLEDAI) score was significantly lower in group 1/2 than group 3 patients (13.5±4.9 vs 18.0±5.3 points;p<0.001). Extra-renal activity was less common in group 1/2 than group 3 patients, but the difference was only statistically significant for arthritis (25%vs42%;p=0.04). All patients were treated with high-dose prednisolone and either MMF (N=72) or Tac (N=69) assigned by random for induction, followed by low-dose prednisolone and azathioprine for maintenance (mean dose: 84.1±23mg/day). Complete response to induction treatment at 6 months, defined as urine P/Cr of <1.0, resolution of active urine sediments, improvement in lupus serology and stabilization of CrCl, was less common with group 1/2 than group 3 patients (45%vs62%;p=0.10). After an observation of 48.5±21 months, the cumulative risk of loss in 30% of CrCl compared to baseline was 4.6% at year 1, 6.3% at year 3 and 18% at year 5. Group 1/2 patients did not differ significantly from group 3 patients in terms of decline in CrCl (HR0.46[0.15-1.46];p=0.19, adjusted for age, sex, SLE duration, initial CrCl and treatment arms). There were 4 arterial events (2 acute coronary syndrome; 2 cerebrovascular accidents) and 1 venous event (deep vein thrombosis)- all occurred in group 1/2 patients (compared with group 3;p=0.01). Infections (major and minor) were numerically more common in group 1/2 than group 3 patients but the difference was insignificant. Conclusions The presence of histological membranous component in lupus nephritis is associated more proteinuria, better renal function but less active lupus serology or extra-renal activity at presentation. One-third of patients have either normal complements or anti-dsDNA, and complete response to induction therapy is less likely. Renal function decline in membranous lupus nephropathy is no different from proliferative lupus nephritis at 5 years, but thrombotic complications are more frequent. Disclosure of Interest None Declared