Early detection of contrast-associated acute kidney injury after coronary angiography: A predictive value of osteopontin.

Abstract

Background: Contrast-associated acute kidney injury (CA-AKI) is a common and serious complication of percutaneous coronary intervention (PCI). It is linked to higher rates of morbidity and mortality. Early detection of patients at risk is crucial for implementing timely preventive actions. Osteopontin (OPN), a multifunctional glycoprotein highly expressed in kidney tissue, has been suggested as a potential biomarker for AKI. However, its role in CA-AKI remains unclear.

Aim: To evaluate the predictive value of serum OPN levels for early identification of CA-AKI in patients undergoing PCI and to compare its diagnostic performance with the Mehran risk score and traditional clinical predictors.

Methods: A prospective, non-randomized comparative study was conducted at Assiut University Hospitals between March 2023 and March 2024. A total of 155 patients who underwent elective or primary PCI were enrolled. Exclusion criteria included chronic kidney disease, prior CA-AKI, cardiogenic shock, obstructive uropathy, malignancy, or nephrotoxic drug use. Serum OPN was measured immediately before and after PCI by ELISA alongside routine renal function tests. CA-AKI was defined as ≥ 0.3 mg/dL absolute or ≥ 50% relative rise in serum creatinine within 7 days post-contrast. The primary outcomes were the rate of CA-AKI after PCI and changes in OPN levels. Patients with CA-AKI were compared with patients without CA-AKI. Logistic regression and receiver operating characteristic curve analyses were performed to assess predictors and diagnostic accuracy.

Results: CA-AKI occurred in 20 patients (12.9%). These patients were significantly older (59.54 ± 8.67 years) than those without CA-AKI (48.19 ± 7.89 years; P < 0.001). Patients with CA-AKI had significantly higher OPN levels before and after PCI compared with those without CA-AKI (P < 0.001). Independent predictors of CA-AKI included pre-PCI OPN [odds ratio (OR) = 3.22], post-PCI OPN (OR = 2.90), contrast volume (OR = 1.22), and Mehran score (OR = 3.10). Pre-PCI OPN > 69.6 ng/mL demonstrated 86.8% accuracy (area under the curve of 0.80). Combining OPN with the Mehran score produced a diagnostic accuracy of 88% (area under the curve of 0.95).

Conclusion: Elevated OPN levels, both before and after PCI, independently predicted CA-AKI and enhanced the predictive power of the Mehran score. Routine assessment of OPN may provide an effective strategy for early risk stratification in patients undergoing PCI.