Use of height-independent baseline creatinine imputation method with renal angina index

  • Jean-Philippe RoyEmail author
  • Catherine Johnson
  • Bryan Towne
  • Frank Menke
  • Samuel Kiger
  • William Young
  • Rajit Basu
  • Ranjit Chima
  • Lin Fei
  • Kelli Krallman
  • Stuart L. Goldstein
Original Article
Part of the following topical collections:
  1. What’s new in AKI



The Renal Angina Index (RAI) is a validated screening tool used at 12 h of pediatric intensive care unit (PICU) admission to predict severe acute kidney injury (AKI) on day 3 of PICU stay. A measured or height-imputed baseline serum creatinine (SCr) is required for AKI diagnosis and RAI calculation, yet these are often lacking. We assessed an age-based, height-independent baseline SCr calculation and compared the RAI values employing this method to their historical counterpart.


An electronic algorithm was implemented to generate RAI score for patients admitted to our PICU. We reviewed 157 consecutive patient records from May 2017, until we cumulated 100 with a valid RAI calculation. We compared RAI scores using the age-based SCr imputation method of Pottel to the historical RAI. Our primary outcome was a difference in the rate of RAI fulfillment (≥ 8) reclassification between methods.


Of the first 100 patients, 27 had measured baseline SCr and 73 used height imputation. Only two patients had RAI reclassified with the Pottel method (one in each direction). Being small for age or older were associated with ≥ 25% overestimation of the baseline SCr in 20 patients with the Pottel method compared with height imputation. 15/157 patients had a falsely positive RAI due to lack of measured baseline SCr and height.


The age-based method to estimate baseline SCr offers a viable height-independent alternative for RAI calculation. While less precise than a height-based approach, this lack of precision rarely leads to reclassification of patient RAI status.


Creatinine Baseline Height-independent Renal angina index Acute kidney injury 


Funding information

This work was supported by the National Institutes of Diabetic, Digestive and Kidney Diseases (P50DK096418-06) and a Cincinnati Children’s Hospital Medical Center Innovation Fund Award.

Compliance with ethical standards



Supplementary material

467_2019_4294_MOESM1_ESM.docx (13 kb)
ESM 1 (DOCX 13 kb)


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Copyright information

© IPNA 2019

Authors and Affiliations

  • Jean-Philippe Roy
    • 1
    Email author
  • Catherine Johnson
    • 2
  • Bryan Towne
    • 2
  • Frank Menke
    • 2
  • Samuel Kiger
    • 2
  • William Young
    • 2
  • Rajit Basu
    • 3
  • Ranjit Chima
    • 4
    • 5
  • Lin Fei
    • 6
  • Kelli Krallman
    • 1
  • Stuart L. Goldstein
    • 1
    • 5
  1. 1.Center for Acute Care NephrologyCincinnati Children’s Hospital Medical CenterCincinnatiUSA
  2. 2.Department of Information ServicesCincinnati Children’s Hospital Medical CenterCincinnatiUSA
  3. 3.Division of Pediatric Critical Care MedicineChildren’s Healthcare of AtlantaAtlantaUSA
  4. 4.Division of Critical Care MedicineCincinnati Children’s Hospital Medical CenterCincinnatiUSA
  5. 5.University of Cincinnati College of MedicineCincinnatiUSA
  6. 6.Division of Biostatistics and EpidemiologyCincinnati Children’s Hospital Medical CenterCincinnatiUSA

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