Abstract: TH-PO118

The Relationship between Interstitial Fibrosis and Tubular Atrophy Scores and Adverse Renal Outcomes among Patients with Primary Membranous Nephropathy: A Retrospective Study

Session Information

Category: Glomerular

  • 1004 Clinical/Diagnostic Renal Pathology and Lab Medicine

Authors

  • Durcan, Martin E., Royal Preston Hospital , Preston, Lancashire, United Kingdom
  • Elsayed, Mohamed, Royal Preston Hospital , Preston, Lancashire, United Kingdom
  • Ponnusamy, Arvind, Royal Preston Hospital , Preston, Lancashire, United Kingdom
Background

Primary Membranous Nephropathy (MGN) is a major cause of adult onset nephrotic syndrome. The severity of interstitial fibrosis and tubular atrophy (IF/TA) has long been used in the prognostication of some glomerulopathies and renal allografts, little is known about their effect on MGN outcomes. The aim of this study was to investigate the association of IF/TA with adverse renal outcomes among a cohort of patients with biopsy-proven primary MGN.

Methods

A cohort of all patients diagnosed with biopsy-proven primary MGN between 2004 to 2011 was constructed. Follow up was until November 2016. Data was retrieved retrospectively.Renal biopsies were scored for (IF/TA) as 0 (absent/focal), 1(moderate) and 2(severe). Primary outcome was a composite of the following endpoints; doubling of baseline creatinine, start of renal replacement therapy or death. Achieving remission was a secondary outcome. Univariate and adjusted Cox regression models were used to calculate hazard ratios with 95% CI for each IF/TA group.

Results

129 incident patients were followed for a median of 5.56 years. 33.3% were females with the remainder being male. Mean age was 56.4 ±16 years. Baseline mean eGRF was 62.9 ± 34.6 ml/min/1.73m2 and PCR was 769.83 mg/mmol. Patients with IF/TA scores of 0,1 and 2 represented 72.5%, 17.5%and 6.8%, respectively. Unadjusted analysis revealed that patients with IF/TA scores of 1 and 2, in reference to IF/TA=0, were at elevated risk to develop the study primary outcome, HR 2.05 [95% CI, 1.04-4.17] and HR 2.73, [95% CI, 1.03-7.26], respectively. However, when adjusted for potential confounders, higher IF/TA scores were no longer associated with adverse outcomes, HR 1.78 [95% CI, 0.39-8.20] for IF/TA=1 and HR 1.62 [95% CI, 0.09-12.95] for IF/TA=2. Furthermore, those with lower scores didn’t have greater likelihood to achieve remission, HR 0.69 [95%CI, 0.31-1.56] for IF/TA=1 and HR 0.34 [95%CI, 0.47-2.52] for IF/TA=2 (reference: IF/TA=0).

Conclusion

The degree of IF/TA on renal biopsy did not predict adverse outcomes among patients with primary membranous nephropathy. Moreover, it was not associated with a higher likelihood to attain remission. We propose that management not be dictated by IF/TA scores. Patients with severe IF/TA should still be considered for treatment.