Abstract: FR-PO074

Urine Injury Biomarker Level before and after AKI: Results from the CRIC Study and CKD Biomarker Consortium

Session Information

  • AKI Clinical: Predictors
    November 03, 2017 | Location: Hall H, Morial Convention Center
    Abstract Time: 10:00 AM - 10:00 AM

Category: Acute Kidney Injury

  • 003 AKI: Clinical and Translational

Authors

  • Hsu, Chi-yuan, University of California San Francisco, San Francisco, California, United States
  • Kimmel, Paul L., National Institute of Diabetes and Digestive Kidney Diseases (NIDDK), Bethesda, Maryland, United States
  • Lunn, Mitchell R., University of California, San Francisco, San Francisco, California, United States
  • Mifflin, Theodore E., University of Pennsylvania, Wilmington, Delaware, United States
  • Ricardo, Ana C., University of Illinois at Chicago, Chicago, Illinois, United States
  • Waikar, Sushrut S., Harvard Medical School, Boston, Massachusetts, United States
  • Yang, Jingrong, Kaiser Permanente, Oakland, California, United States
  • Liu, Kathleen D., University of California at San Francisco School of Medicine, San Francisco, California, United States
  • Xie, Dawei, University of Pennsylvania School of Medicine Center for Clinical Epidemiology and Biostatistics, Philadelphia, Pennsylvania, United States
  • Zhang, Xiaoming, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States
  • Bonventre, Joseph V., Brigham and Women's Hospital, Boston, Massachusetts, United States
  • Chen, Jing, Tulane School of Medicine, New Orleans, Louisiana, United States
  • Drawz, Paul E., University of Minnesota, Minneapolis, Minnesota, United States
  • Feldman, Harold I., University of Pennsylvania, Wilmington, Delaware, United States
  • Go, Alan S., Kaiser Permanente Northern California, Oakland, California, United States
  • Horwitz, Edward J., None, Solon, Ohio, United States
Background

Change in serum creatinine (SCr) estimated glomerular filtration rate (GFR) may underestimate the renal sequelae of AKI since SCr rise after AKI may be blunted due to loss of muscle mass, decreased creatinine production, compensatory increase in single nephron GFR and other factors. Changes in levels of sensitive tubular injury biomarkers may capture more subtle persistent damage to the kidneys following an episode of mild-moderate AKI.

Methods

We studied a subset of Chronic Renal Insufficiency (CRIC) participants enrolled from Kaiser Permanente Northern California (KPNC) who had urine specimen banked as part of annual research study visits. We used data gathered as part of clinical care and captured in the KPNC electronic medical record to define episodes of AKI (peak/nadir inpatient SCr >1.5). We measured level of kidney injury molecule-1 (KIM-1) in urine samples collected at the annual CRIC study visit before the AKI episode and urine samples collected at the annual CRIC study visit after the AKI episode. We compared 29 participants with documented AKI (69% with KDIGO severity stage 1; 10% stage 2; 21% stage 3) with 157 participants who did not (matched for calendar year and time gap between first and second measurement [overall mean 419 days]).

Results

Overall, 70% of participants were female; 48% were white/39% black and 70% had diabetes mellitus; mean age was 63 yrs, eGFR 49 ml/min/1.73m2 and urine albumin/Cr ratio (ACR) 21 mg/mg. Although there were no change in eGFR or ACR from pre-AKI to post-AKI (Table), rise in urine KIM-1/Cr was greater for patients who had AKI vs. those who did not (median delta 381 vs. 46 ng/g; p<0.002)(Table).

Conclusion

These data suggests there is persistent tubular injury months after an episode of mild to moderate AKI.

 Non-AKIAKIp-value
Change in eGFR, ml/min/1.73m2, median [IQR]0 [-4, 5]-1 [-5, 4]0.417
Change in ACR, mg/gm, median [IQR]2 [-5, 14]2 [-9, 87]0.650
KIM-1/Cr pre-AKI, ng/g, median [IQR]524 [311, 952]804 [452, 1463]0.026
KIM-1/Cr post-AKI, ng/g, median [IQR]581 [365, 1009]1053 [555, 2864]0.002
Change in KIM-1/Cr, ng/g, median [IQR]46 [-246, 293]381 [-107, 1264]0.019

Funding

  • NIDDK Support