Abstract: TH-PO239

Flow Cytometric Detection of Urinary Renal Tubular Epithelial Cells Directly Reflects Kidney Damage and Predicts Recovery from AKI

Session Information

Category: Acute Kidney Injury

  • 001 AKI: Basic

Authors

  • Enghard, Philipp, Charité, Berlin, Germany
  • Langhans, Valerie Stephanie, Charité Universitätsmedizin Berlin, Berlin, Germany
Background

Acute kidney injury (AKI) is among the most frequent causes for renal damage and associated with significant increase of morbidity and mortality. Renal Tubular epithelial cells (TEC) are arguably the main target cell of AKI. The objective of our study was to establish flow cytometry based detection of different TECs in the urine and assess these cells as a biomarker for AKI.

Methods

Urine samples of 28 patients with AKI and 5 healthy controls were collected, immediately washed and the cells fixed using 2% formaldehyde. Proximal and distal TECs were identified using a staining for Cytokeratine (all TECs), CD10 (proximal TECs) and EPCAM (distal TECs). The amount of TECs per 100ml urine was correlated to AKIN stadium and subsequent recovery/non-recovery from AKI.

Results

Urinary numbers of TECs were increased upon kidney injury and only slowly decreased during recovery. TEC counts correlated with AKIN stadium of the patients (p=0.0006, r=0.57 proximal and p< 0.0001, r=0.67, for distal TECs, Spearman). TEC numbers were significantly higher in patients with AKI than in healthy donors and enabled to distinguish between different AKIN stadia. Importantly, the amount of distal TECs (Cytokeratine+EPCAM+) upon AKI was able to predict subsequent recovery/non-recovery from AKI. Applying a cut-off of 200.000 cells/100ml urine separated patients with and without recovery (Cytokeratine+EPCAM+, p= 0.0068).

Conclusion

Urinary cell counts of renal epithelial cells directly reflect the amount of tissue damage in human AKI. Our findings suggest proximal and distal TECs as biomarkers to diagnose and estimate the severity of kidney damage and to predict the outcome of patients with AKI.

Funding

  • Private Foundation Support