Renal angina index versus serum creatinine for early prediction of acute kidney injury in critically ill children: a prospective observational study

Bhavya Bhavana; B. Santosh Avinash

doi:10.18203/2349-3291.ijcp20263300

Authors

Bhavya Bhavana Department of Paediatrics, Osmania Medical College, Hyderabad, Telangana, India
B. Santosh Avinash Department of Paediatrics, Osmania Medical College, Hyderabad, Telangana, India

DOI:

https://doi.org/10.18203/2349-3291.ijcp20263300

Keywords:

Acute kidney injury, Renal angina index, Pediatric intensive care, Serum creatinine, KDIGO, Early prediction

Abstract

Background: Acute kidney injury (AKI) is common in critically ill children, while serum creatinine is a delayed marker of renal dysfunction. The Renal Angina Index (RAI) combines clinical risk and early signs of renal injury and may permit earlier identification of children likely to develop severe AKI.

Methods: This prospective observational study included 150 children aged 1 month-12 years admitted to a tertiary-care pediatric intensive care unit. RAI was calculated 12-24 hours after admission; a score ≥8 was considered positive. The primary outcome was severe AKI (KDIGO stage 2 or 3) by Day 3. Diagnostic performance of RAI was compared with Day-1 serum creatinine using receiver operating characteristic analysis.

Results: AKI occurred in 55/150 (36.7%) children and 52/150 (34.7%) were RAI positive. Mean RAI was higher in children with AKI than without AKI (9.65±3.23 vs 3.05±1.78; p<0.001). RAI had sensitivity 81.8%, specificity 92.6%, positive predictive value 86.5%, negative predictive value 89.8%, and accuracy 88.7%. Its area under the ROC curve was 0.928 (95% CI 0.887-0.969), compared with 0.307 (95% CI 0.208-0.405) for Day-1 serum creatinine.

Conclusions: RAI was a strong early predictor of AKI in critically ill children and substantially outperformed Day-1 serum creatinine. As a low-cost bedside score using routinely available data, it may facilitate early risk stratification in resource-limited PICUs.

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References

Sankannavar A, Shivaramaiah KD, Puttalinga D. Renal angina index as a predictor of acute kidney injury development in critically ill children admitted to pediatric critical care units: a prospective observational study. J Pediatr Emerg Intensive Care Med. 2024;11(3):167-73. DOI: https://doi.org/10.4274/cayd.galenos.2024.67044

Gawadia J, Mishra K, Kumar M, Saikia D. Prediction of severe acute kidney injury using renal angina index in a pediatric intensive care unit. Indian Pediatr. 2019;56(8):647-52. DOI: https://doi.org/10.1007/s13312-019-1587-2

Sadeghi-Bojd S, Noori NM, Mohammadi M, Teimouri A. Clinical characteristics and mortality risk prediction in children with acute kidney injury. Niger Med J. 2015;56(5):327-32. DOI: https://doi.org/10.4103/0300-1652.170381

Dabour SA, Elgendy SA, Abdel Rahman EG, Zayed EM. Prediction of acute kidney injury using renal angina index in pediatric intensive care unit. Benha J Appl Sci. 2020;5(4 Pt 1):39-44. DOI: https://doi.org/10.21608/bjas.2020.136139

Jakanattane V, Sivakumar E, Rajkumar D, Kulandaivel M. Validation of renal angina index (RAI) to improve the prediction of acute kidney injury (AKI) in critically ill children admitted to paediatric intensive care unit (PICU). Int J Contemp Pediatr. 2017;4(6):2158-64. DOI: https://doi.org/10.18203/2349-3291.ijcp20174749

Goldstein SL, Chawla LS. Renal angina. Clin J Am Soc Nephrol. 2010;5(5):943-9. DOI: https://doi.org/10.2215/CJN.07201009

Nicolau B, Costa-Reis P. Advances in pediatric acute kidney injury prevention and early diagnosis. Port J Nephrol Hypert. 2022;36(3):130-7. DOI: https://doi.org/10.32932/pjnh.2022.08.196

Rivetti G, Gizzone P, Petrone D, Di Sessa A, Miraglia Del Giudice E, Guarino S, et al. Acute kidney injury in children: a focus for the general pediatrician. Children (Basel). 2024;11(8):1004. DOI: https://doi.org/10.3390/children11081004

Raina R, Chakraborty R, Tibrewal A, Sethi SK, Bunchman T. Advances in pediatric acute kidney injury. Pediatr Res. 2022;91(1):44-55. DOI: https://doi.org/10.1038/s41390-021-01452-3

Plumb L, Casula A, Sinha MD, Inward CD, Marks SD, Medcalf J, et al. Epidemiology of childhood acute kidney injury in England using e-alerts. Clin Kidney J. 2023;16(8):1288-97. DOI: https://doi.org/10.1093/ckj/sfad070

Kopač M. Acute kidney injury in children: classification, recognition and treatment principles. Children (Basel). 2024;11(11):1308. DOI: https://doi.org/10.3390/children11111308

Selewski DT, Charlton JR, Jetton JG, Guillet R, Mhanna MJ, Askenazi DJ, et al. Neonatal acute kidney injury. Pediatrics. 2015;136(2):e463-73. DOI: https://doi.org/10.1542/peds.2014-3819

Ruas FL, Malheiros Lébeis G, Bianco de Castro N, Andrade Palmeira V, Braga Costa L, Lanza K, et al. Acute kidney injury in pediatrics: an overview focusing on pathophysiology. Pediatr Nephrol. 2022;37(9):2037-52. DOI: https://doi.org/10.1007/s00467-021-05346-8

Triebel H, Castrop H. The renin angiotensin aldosterone system. Pflugers Arch. 2024;476(5):705-13. DOI: https://doi.org/10.1007/s00424-024-02908-1

Kidney Disease: Improving Global Outcomes Acute Kidney Injury Work Group. KDIGO clinical practice guideline for acute kidney injury. Kidney Int Suppl. 2012;2(1):1-138.

Guarino S, Rivetti G, Di Sessa A, De Lucia M, Palma PL, Miraglia Del Giudice E, et al. Diagnostic performance of height-estimated basal creatinine in diagnosing acute kidney injury in children with type 1 diabetes mellitus onset. Children (Basel). 2022;9(6):899. DOI: https://doi.org/10.3390/children9060899

Kuok MCI, Chan WKY. Advances in pediatric acute kidney injury detection and prediction: biomarkers and artificial intelligence. World J Pediatr. 2025;21(9):865-71. DOI: https://doi.org/10.1007/s12519-025-00965-9

Wasung ME, Chawla LS, Madero M. Biomarkers of renal function, which and when? Clin Chim Acta. 2015;438:350-7. DOI: https://doi.org/10.1016/j.cca.2014.08.039

Sethi SK, Bunchman T, Chakraborty R, Raina R. Pediatric acute kidney injury: new advances in the last decade. Kidney Res Clin Pract. 2021;40(1):40-51. DOI: https://doi.org/10.23876/j.krcp.20.074

Jetton JG, Askenazi DJ. Acute kidney injury in the neonate. Clin Perinatol. 2014;41(3):487-502. DOI: https://doi.org/10.1016/j.clp.2014.05.001

Naik S, Sharma J, Yengkom R, Kalrao V, Mulay A. Acute kidney injury in critically ill children: risk factors and outcomes. Indian J Crit Care Med. 2014;18(3):129-33. DOI: https://doi.org/10.4103/0972-5229.128701

Sagri MN, Rehman B, Akbar A, Jamshed Y, Zahid S, Ishaque S. Utility of renal angina index as compared to KDIGO in critically ill children at a tertiary care hospital in a low middle-income country. BMC Pediatr. 2026;26(1):101. DOI: https://doi.org/10.1186/s12887-025-06106-5

Washburn KK, Zappitelli M, Arikan AA, Loftis L, Yalavarthy R, Parikh CR, et al. Urinary interleukin-18 is an acute kidney injury biomarker in critically ill children. Nephrol Dial Transplant. 2008;23(2):566-72. DOI: https://doi.org/10.1093/ndt/gfm638

Basu RK, Zappitelli M, Brunner L, Wang Y, Wong HR, Chawla LS, et al. Derivation and validation of the renal angina index to improve the prediction of acute kidney injury in critically ill children. Kidney Int. 2014;85(3):659-67. DOI: https://doi.org/10.1038/ki.2013.349

Cho MH. Pediatric acute kidney injury: focusing on diagnosis and management. Child Kidney Dis. 2020;24(1):19-26. DOI: https://doi.org/10.3339/jkspn.2020.24.1.19

Attalla HA, Ahmed AM. Prediction of acute kidney injury in critically-ill pediatric patients admitted to PICU: the role of serum cystatin C and serum interleukin-18. Egypt J Hosp Med. 2020;80:943-50. DOI: https://doi.org/10.21608/ejhm.2020.103660

Soliman ASA, Al-Ghamdi HS, Abukhatwah MW, Kamal NM, Dabour SA, Elgendy SA, et al. Renal angina index in critically ill children as an applicable and reliable tool in the prediction of severe acute kidney injury: two tertiary centers' prospective observational study from the Middle East. Medicine (Baltimore). 2023;102(51):e36713. DOI: https://doi.org/10.1097/MD.0000000000036713

Kumar BM, Karpagam L, Umamaheshwari BM, Ali BMA. A comparative study on renal anginal index vs serum creatinine as a predictor of acute kidney injury in a pediatric intensive care unit. Int J Acad Med Pharm. 2023;5(6):1252-8.

Mehta P, Sinha A, Sami A, Hari P, Kalaivani M, Gulati A, et al. Incidence of acute kidney injury in hospitalized children. Indian Pediatr. 2012;49(7):537-42. DOI: https://doi.org/10.1007/s13312-012-0121-6

Sundararaju S, Sinha A, Hari P, Lodha R, Bagga A. Renal angina index in the prediction of acute kidney injury in critically ill children. Asian J Pediatr Nephrol. 2019;2(1):25-30.