ASN's Mission

ASN leads the fight to prevent, treat, and cure kidney diseases throughout the world by educating health professionals and scientists, advancing research and innovation, communicating new knowledge, and advocating for the highest quality care for patients.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on Twitter

Kidney Week

Abstract: SA-PO535

Synergistic Effects of Glomerular Lesion and Interstitial Lesion on Increased Proteinuria But Not on Renal Prognosis

Session Information

Category: Diabetic Kidney Disease

  • 602 Diabetic Kidney Disease: Clinical

Authors

  • Eriguchi, Masahiro, Nara Medical University, Kashihara, Nara, Japan
  • Kosugi, Takaaki, Nara Medical University, Kashihara, Nara, Japan
  • Nishimoto, Masatoshi, Nara Medical University, Kashihara, Nara, Japan
  • Tsushima, Hideo, Nara Medical University, Kashihara, Nara, Japan
  • Tanabe, Kaori, Nara Medical University, Kashihara, Nara, Japan
  • Morimoto, Katsuhiko, Nara Prefecture Western Medical Center, Ikoma-gun, Nara, Japan
  • Matsui, Masaru, Nara Prefecture General Medical Center, Nara, NARA, Japan
  • Tagawa, Miho, Nara Medical University, Kashihara, Nara, Japan
  • Samejima, Ken-ichi, Nara Medical University, Kashihara, Nara, Japan
  • Tsuruya, Kazuhiko, Nara Medical University, Kashihara, Nara, Japan
Background

Diabetic kidney disease (DKD), a recently proposed concept, is associated with various proteinuria level and heterogeneous renal prognosis; however, these patients are rarely examined by renal biopsy. We have biopsy-proven diabetic nephropathy (DN) cohort including many patients with relatively mild proteinuria. That encouraged us to examine the association between histological findings and variation in proteinuria level and renal prognosis in DKD.

Methods

This is a longitudinal study of 396 adults with biopsy-proven DN from 1981 to 2014. Predictors were renal pathological findings. DN was evaluated by two renal pathologists according to 13 histological findings (9 glomerular lesions, 2 tubulointerstitial lesions and 2 vascular lesions). Cross-sectional association with proteinuria level was examined with multivariable general linear model and two-way analyses of covariate and variance, and longitudinal association with renal prognosis was examined with Cox regression model.

Results

Median proteinuria level was 0.5 g/day (25th and 75th percentile: 0.2 and 2.6 g/day) at the time of renal biopsy. During mean follow-up of 9.7 years, 99 patients reached end-stage kidney disease (ESKD). Among thirteen histological findings, nodular lesion (NL) and interstitial fibrosis and tubular atrophy (IFTA) were significant predictors for proteinuria levels after adjustment for clinical risk factors. Among patients with NL or >25% IFTA, 31% of patients had only IFTA and 20% had only NL. NL and IFTA had a synergetic effect on increased proteinuria after adjustment with clinical parameters (p for interaction=0.07). Cox regression analysis showed NL and IFTA were significantly associated with a development of ESKD but there was not a synergetic effect on renal prognosis between these two factors (p for interaction=0.94).

Conclusion

These data suggest the fluctuation in the balance between glomerular and interstitial damages could interpret various degrees of proteinuria and heterogeneous renal prognosis in DKD.