Serum Dickkopf-3 as a biomarker for predicting acute kidney injury in postoperative intensive care patients.

Background: Acute kidney injury (AKI) is a common and significant complication in the Intensive Care Unit (ICU), affecting more than half of all patients admitted. This condition is associated with increased morbidity and mortality, underscoring the urgent need for accurate and specific biomarkers to enable early diagnosis and intervention. Dickkopf-3 (DKK3) has emerged as a promising candidate biomarker for renal injury.

Methods: We conducted a single-center, prospective cohort study from March 1 to July 1, 2023, enrolling 166 non-cardiac postoperative patients admitted to the ICU. Serum and urinary DKK3 levels were quantified using enzyme-linked immunosorbent assay (ELISA) kits. A multifactorial logistic regression model was constructed, incorporating changes in serum creatinine (ΔScr), cystatin C (CysC), serum DKK3 levels, and the serum DKK3 to urine DKK3 ratio.

Results: Elevated serum DKK3 levels were significantly associated with an increased incidence of AKI and a composite outcome of adverse events (AKI or death). The multifactorial logistic regression model exhibited excellent performance, with an area under the receiver operating characteristic curve (AUC) of 0.98. Decision curve analysis (DCA) demonstrated a net clinical benefit of utilizing serum DKK3 levels to guide treatment decisions, particularly at higher risk thresholds.

Conclusions: Serum DKK3 is a robust diagnostic biomarker for AKI, effectively stratifying patients based on protein levels. The predictive model that incorporates DKK3 provides a valuable tool for clinical decision-making in the ICU setting. Further validation in larger and more diverse populations is warranted.