Primary and secondary glomerulonephritis I

2 Essalud Introduction and Aims: Progression and long-term renal outcome of proliferative lupus nephritis (PLN) in people from peruvian amazonic region is an uninvestigated subject in the literature. The aim of this study was to evaluate the influence of amazonic race of peruvian people on the renal outcome of PLN in comparison with the rest of the patients. Methods: All patients who fulfilled American College of Rheumatology lupus criteria and who were referred for a kidney biopsy from 2000 to 2010 were enrolled in the study. Subjects with end- stage renal disease (ESRD) at baseline, or follow-up time below 6 months, were excluded. Cases were randomly matched to Amazonic race (A) and Others (O) patients according to the class of LN, SLEDAI score, baseline estimated glomerular filtration rate (eGFR, Modification of Diet in Renal Disease simplified formula), ANA, Anti DNA, C3 levels, serum albumin, clinical onset and follow-up time. Treatment was decided by the clinical staff based on usual literature protocols. The primary endpoint was doubling of serum creatinine and/or ESRD. The secondary endpoint was defined as a variation of (GFR) per year (δGFR/y index), calculated as the difference between final and initial eGFR adjusted by follow-up time for each patient. Results: We included 92 patients (28 A: 64 O). At baseline, A and O patients were not statistically different regarding WHO LN class (III 18.5% IV 71.7%, V 9.8%), eGFR (A 62.4 + 36.4 versus F 60.1 + 27.2 ml/min/1.73m2), follow-up time (A 64.2 + 27.8 versus O 59.9 + 26.9 months), and 24-hour proteinuria (A 3.3 + 1.6 versus O 2.9 + 1.4 g/day), as well as age, albumin, C3, antinuclear antibody, anti-DNA antibody, haematuria and SLEDAI score. There was significative difference in the primary outcome (A 53.6% versus F 12.5%, log-rank p = 0.62). Same way, amazonic race was significantly associated with a worse renal function progression, as measured by δGFR/y index (β coefficient for amazonic race -11.9, 95% confidence interval -23.1.8 to -2.3, p = 0.03). The multivariate linear regression model showed that peruvian amazonic race remained statistically associated with a worse renal outcome even after adjustment for eGFR, proteinuria, albumin and C3 complement at baseline Conclusions: In our study, amazonic race presented a worse evolution of LN when compared with the rest of patients with similar baseline features and treatment. Factors that influence the progression of LN in amazonic people should be further studied.