CT-Based Perfusion Assessment for the Early Detection of Acute Kidney Injury After Earthquake-Induced Crush Syndrome

The early detection of acute kidney injury (AKI) following crush injury is crucial for prompt intervention. The CT-based cortex-to-aorta enhancement index (CAEI) which is calculated from contrast-enhanced computed tomography (CT) scans, reflects abdominal organ perfusion and could serve as a rapid, quantitative imaging biomarker for AKI risk. This study aims to investigate the predictive value of the CAEI for AKI in patients with crush injuries and to compare it with that of conventional biochemical markers. This retrospective analysis involved performing enhanced abdominal CT scans on 107 patients (mean age 43.9 years; 55 men and 52 women) with crush injuries. The CAEI was quantified from standard regions of interest in the renal cortex and the abdominal aorta. Serum creatine kinase (CK), lactate dehydrogenase (LDH), creatinine, potassium and calcium levels were assessed. AKI was diagnosed on the basis of established clinical criteria. Twenty-seven patients (25.2%) developed AKI. The CAEI was significantly lower in AKI patients than in non-AKI patients (mean: 0.95 vs. 1.13; p < 0.001). ROC analysis revealed that the CAEI was an effective predictor of AKI (AUC = 0.83; 95% CI 0.69–0.97), with performance comparable to log-transformed CK (AUC = 0.90; 95% CI 0.75–1.00; p = 0.20 for comparison). In multivariable analysis with standardized predictors, CAEI (per 1 SD decrease: OR = 4.12; 95% CI 1.52–11.14; p = 0.005) and log-CK (per 1 SD increase: OR = 6.91; 95% CI 2.45–19.44; p < 0.001) remained independent predictors of AKI, whereas LDH, creatinine, potassium, age, sex, and time under rubble were not. CAEI is a robust and independent predictor of AKI in patients with crush injuries, performing at least as well as conventional biochemical markers. Including CAEI in emergency CT protocols allows both trauma assessment and AKI risk stratification to be performed simultaneously, eliminating the need for additional imaging. This is particularly useful in mass casualty situations.