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Abstract: SA-PO1029

No Need for Beef: A New Vegetarian Test to Measure Renal Functional Reserve

Session Information

Category: Pathology and Lab Medicine

  • 1800 Pathology and Lab Medicine


  • Huidobro, Juan Pablo, Pontificia Universidad Catolica de Chile, Santiago, Chile
  • Sepúlveda, Rodrigo, Pontificia Universidad Catolica de Chile, Santiago, Chile
  • Vega, Jorge E., Universidad de Valparaiso, Valparaiso, Chile

Renal functional reserve (RFR) corresponds to the physiologic increase in glomerular filtration rate (GFR) after a stimulus. It can be measured to evaluate living kidney donor candidates, risk and recovery of AKI in critical care situations and even risk of pre-eclampsia.
The most frequently used test to measure RFR is by ingesting an oral load of protein from animal meat. We aimed to develop an alternative test to measure RFR without the need of meat consumption using L-arginine, a precursor of nitric oxide. Herein, we present the results of a pilot study.


A 4-hour creatinine clearance (ClCr) was measured in 7 healthy individuals in whom eGFR by CKD-EPI equation was 103.9 mL/min/1.73m2 (range 92.3-113.4) after a day of plant-based diet and normal ingestion of fluids. The next day, at the same hour, a new 4-hour CrCl was measured, this time after the ingestion of 5 grs of L-Arginine 1 hour before the start of urine collection. RFR was calculated as the difference between indexed post-L-Arginine CrCl and indexed basal CrCl.


Median basal CrCl was 124.6 mL/min/1.73m2 (range 54.7-162). Post- L-Arginine CrCl was significantly augmented to 145.4 mL/min/1.73m2 (range 81.1-179.7) (p<0.05). Median RFR was 20.8 mL/min/1.73m2 (range -7.6-48.9) . No adverse effects were reported.


Evaluation of RFR can be safely done using L-Arginine stimulation and could be considered as an alternative to meat consumption in vegetarian population.
This preliminary data needs to be confirmed in a larger cohort. The optimal dosing of L-Arginine for this purpose should be determined in larger studies.