Novel urinary biomarkers and the early detection of acute kidney injury after open cardiac surgeries

Highlights • Patients with AKI had a higher AKIN stages and CCS. CPB time and cross clamp time were significantly higher in the AKI group • Serum creatinine started to be significantly higher in AKI group from the second postoperative day with a mean value of 1.56 ± 0.28 mg/dl compared to a mean value of 0.85 ± 0.14 mg/dl in non-AKI group. • Urine sediment score (USS) 1 and 2 were higher in the AKI group than in the non-AKI group 2 hrs after CPB and till the end of the 2nd day with area under the curve (AUC) average of (0.865). • Urinary NGAL significantly rise in AKI patients 2 and 6 hr after CPB with corresponding AUC of (0.710 and 0.700) but uKIM-1 was higher in the AKI group 12 and 24 hr after CPB with AUC (0.725 and 0.703) respectively • Distinct from traditional markers of function such as creatinine, the rapid response (within few hours) enables NGAL to potentially identify injured kidney much earlier than was previously possible. • KIM-1 has been proven to be more specific to ischaemic renal injury with early response in the first postoperative day and its combination with the sensitive NGAL may enable more accurate prediction of CSA-AKI. • Although urinary microscopic examination has been neglected for many years by physicians, it was found to be a near ideal renal biomarker with very high sensitivity and specificity and injury site informative.