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Objective: To test the association of osteopontin (OPN) polymorphisms with systemic lupus erythematosus (SLE)., Methods: The coding 5' and 3' flanking regions of the OPN gene were scanned for polymorphisms by denaturing high-performance liquid chromatography. A case-control association study was performed in 394 Italian SLE patients and 479 matched controls. OPN serum levels were determined by enzyme-linked immunosorbent assay in 40 patients and 124 controls, and the mean levels were compared between the different OPN genotypes., Results: Among the 13 detected single-nucleotide polymorphisms (SNPs), alleles -156G (frequency 0.714 versus 0.651; P = 0.006, corrected P [P(corr)] = 0.036) and +1239C (0.377 versus 0.297; P = 0.00094, P(corr) = 0.0056) were significantly increased in the SLE patients compared with the controls. The presence of the associated allele in single or double dose conferred an odds ratio (OR) of 2.35 (95% confidence interval [95% CI] 1.38-4.02) for SNP -156 and an OR of 1.57 (95% CI 1.16-2.13) for SNP +1239. These effects were independent of each other, i.e., not a consequence of linkage disequilibrium between the 2 alleles. The risk associated with a double dose of susceptibility alleles at both SNPs was 3.8-fold higher (95% CI 2.0-7.4) relative to the complete absence of susceptibility alleles. With regard to individual clinical and immunologic features, a significant association was seen between lymphadenopathy and -156 genotypes (overall P = 0.0011, P(corr) = 0.046). A significantly increased OPN serum level was detected in healthy individuals carrying +1239C (P = 0.002), which is indicative of an association between the SLE susceptibility allele and OPN levels., Conclusion: These data suggest the independent effect of a promoter (-156) and a 3'-untranslated region (+1239) SNP in SLE susceptibility. We can speculate that these sequence variants (or others in perfect linkage disequilibrium) create a predisposition to high production of OPN, and that this in turn may confer susceptibility to SLE.

Objective: In the Euro-Lupus Nephritis Trial (ELNT), 90 patients with lupus nephritis were randomly assigned to a high-dose intravenous cyclophosphamide (IV CYC) regimen (6 monthly pulses and 2 quarterly pulses with escalating doses) or a low-dose IV CYC regimen (6 pulses of 500 mg given at intervals of 2 weeks), each of which was followed by azathioprine (AZA). After a median followup of 41 months, a difference in efficacy between the 2 regimens was not observed. The present analysis was undertaken to extend the followup and to identify prognostic factors., Methods: Renal function was prospectively assessed quarterly in all 90 patients except 5 who were lost to followup. Survival curves were derived using the Kaplan-Meier method., Results: After a median followup of 73 months, there was no significant difference in the cumulative probability of end-stage renal disease or doubling of the serum creatinine level in patients who received the low-dose IV CYC regimen versus those who received the high-dose regimen. At long-term followup, 18 patients (8 receiving low-dose and 10 receiving high-dose treatment) had developed permanent renal impairment and were classified as having poor long-term renal outcome. We demonstrated by multivariate analysis that early response to therapy at 6 months (defined as a decrease in serum creatinine level and proteinuria <1 g/24 hours) was the best predictor of good long-term renal outcome., Conclusion: Long-term followup of patients from the ELNT confirms that, in lupus nephritis, a remission-inducing regimen of low-dose IV CYC followed by AZA achieves clinical results comparable with those obtained with a high-dose regimen. Early response to therapy is predictive of good long-term renal outcome.

Objective: Glomerulonephritis is a severe manifestation of systemic lupus erythematosus (SLE) that is usually treated with an extended course of intravenous (IV) cyclophosphamide (CYC). Given the side effects of this regimen, we evaluated the efficacy and the toxicity of a course of low-dose IV CYC prescribed as a remission-inducing treatment, followed by azathioprine (AZA) as a remission-maintaining treatment., Methods: In this multicenter, prospective clinical trial (the Euro-Lupus Nephritis Trial [ELNT]), we randomly assigned 90 SLE patients with proliferative glomerulonephritis to a high-dose IV CYC regimen (6 monthly pulses and 2 quarterly pulses; doses increased according to the white blood cell count nadir) or a low-dose IV CYC regimen (6 fortnightly pulses at a fixed dose of 500 mg), each of which was followed by AZA. Intent-to-treat analyses were performed., Results: Followup continued for a median of 41.3 months in the low-dose group and 41 months in the high-dose group. Sixteen percent of those in the low-dose group and 20% of those in the high-dose group experienced treatment failure (not statistically significant by Kaplan-Meier analysis). Levels of serum creatinine, albumin, C3, 24-hour urinary protein, and the disease activity scores significantly improved in both groups during the first year of followup. Renal remission was achieved in 71% of the low-dose group and 54% of the high-dose group (not statistically significant). Renal flares were noted in 27% of the low-dose group and 29% of the high-dose group. Although episodes of severe infection were more than twice as frequent in the high-dose group, the difference was not statistically significant., Conclusion: The data from the ELNT indicate that in European SLE patients with proliferative lupus nephritis, a remission-inducing regimen of low-dose IV CYC (cumulative dose 3 gm) followed by AZA achieves clinical results comparable to those obtained with a high-dose regimen.