Will urinary biomarkers provide a breakthrough in diagnosing cardiac surgery-associated AKI? – A systematic review

Abstract

Introduction: Acute kidney injury following cardiac surgery is a dreaded complication contributing to early mortality. Diagnosing AKI using serum creatinine usually results in a delay. To combat this, certain kidney damage specific biomarkers were investigated to identify if they can serve as early predictors of cardiac surgery-associated AKI (CSA-AKI). This study systematically reviews three such biomarkers; NGAL, tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) and insulin-like growth factor binding protein-7 (IGFBP7) to identify if they can serve as early predictors of CSA-AKI.

Methods: Systematic search was carried out on literature reporting the diagnostic ability of the three biomarkers from databases in accordance with PRISMA guidelines.

Results: We found 43 articles reporting urinary-NGAL levels (n = 34 in adults, n = 9 in children) and 10 studies reporting TIMP-2 and IGFBP7 levels among adults. Interestingly, NGAL showed high diagnostic value in predicting AKI in children (seven among nine studies with AUROC > 0.8). The cell cycle arrest biomarkers, namely TIMP-2 and IGFBP7, showed high diagnostic value in predicting AKI in adults (five among ten studies with AUROC > 0.8).

Conclusion: In predicting CSA-AKI; the diagnostic value of NGAL is high in the paediatric population while the diagnostic value of TIMP-2 and IGFBP7 is high in adults.

Graphical Abstract

Keywords:

• Acute kidney injury
• biomarkers
• cardiovascular surgery
• insulin-like growth factor binding protein-7 (IGFBP7)
• neutrophil gelatinase-associated lipocalin (NGAL)
• tissue inhibitor of matrix metalloproteinase-2 (TIMP-2)

Acknowledgements

The authors would like to thank Professor Dr. Hassaan Tohid, California Institute of Behavioural Neurosciences and Psychology for his guidance and mentoring in the writing of this article.

Disclosure statement

No potential conflict of interest was reported by the author(s).