Uric Acid to Albumin Ratio for Predicting Contrast Associated Acute Kidney Injury After Cardiac and Non Cardiac Procedures

Contrast-associated acute kidney injury (CA-AKI) is a potential complication that can occur following exposure to iodinated contrast media during diagnostic and interventional procedures, contributing to prolonged hospital stays, increased morbidity, and higher mortality. Although several clinical risk factors are well-recognized, pre-procedural risk stratification remains challenging. The serum uric acid-to-albumin ratio (UAR) has emerged as a composite biomarker reflecting oxidative stress and inflammation that may help identify vulnerable patients prior to contrast exposure. The primary purpose of this prospective observational cohort study is to evaluate the predictive performance of the pre-procedural uric acid-to-albumin ratio for the development of contrast-associated acute kidney injury. The study will also compare the predictive value of UAR between patients undergoing cardiac procedures, specifically percutaneous coronary intervention (PCI), and those undergoing non-cardiac contrast procedures. A total of 100 adult participants will be enrolled across two groups: 50 patients undergoing PCI and 50 patients undergoing non-cardiac contrast procedures. Baseline venous blood samples will be obtained prior to the procedure to measure serum creatinine, uric acid, and albumin levels. Follow-up kidney function tests will be evaluated at 48 and 72 hours post-procedure to detect the development of CA-AKI and assess the diagnostic accuracy of pre-procedural UAR.

Inclusion Criteria: * Adult patients aged 18 years or older undergoing a cardiac or non-cardiac procedure requiring iodinated contrast media. * Cardiac group: patients undergoing percutaneous coronary intervention (PCI). * Non-cardiac group: patients undergoing other diagnostic or interventional contrast procedures. * Provision of written informed consent prior to enrollment. * Available baseline (pre-procedural) serum creatinine, uric acid, and albumin measurements. Exclusion Criteria: * Severe chronic kidney disease or end-stage renal disease on regular maintenance hemodialysis (baseline eGFR \< 15 mL/min/1.73 m\^2). * Exposure to iodinated contrast media within the preceding 7 to 10 days. * Acute kidney injury from any cause present at admission or prior to contrast exposure. * Active infection, sepsis, or systemic inflammatory response syndrome at the time of enrollment. * Known history of gout, current use of urate-lowering therapy, or hematologic malignancy affecting uric acid metabolism. * Severe hepatic disease or marked proteinuria affecting serum albumin independently of the study condition. * Emergent PCI where baseline laboratory samples could not be obtained prior to contrast exposure. * Patient death occurring before the 48 to 72 hour post-procedural serum creatinine evaluation could be performed. * Pregnancy. * Refusal of informed consent or loss to follow-up prior to outcome assessment.