Elevated albumin-corrected anion gap Linked to Increased AKI Risk in Critical acute pancreatitis Patients: Study

A new study published in the journal of BMC Nephrology showed that that elevated albumin-corrected anion gap (ACAG) levels (≥ 20.25 mmol/L) at ICU admission were significantly associated with a higher risk of acute kidney injury (AKI) in critically ill patients suffering from acute pancreatitis (AP).

High incidence, quick progression, and multisystem complications are characteristics of acute pancreatitis (AP), a common severe gastrointestinal illness. One of the most common and deadly complications is acute kidney injury (AKI), which significantly raises the risk of both short- and long-term death.

Severe AP made worse by AKI also increases the risk of death. Multifactorial mechanisms are involved in the pathophysiology of AKI in AP. Particularly in critically ill patients with severe inflammation and hypoproteinemia like AP, the albumin-corrected anion gap (ACAG) can more accurately reflect the true load of unmeasured anions (like lactate and ketone bodies) in the body.

One frequent and dangerous side effect of acute pancreatitis is acute kidney injury (AKI). To prevent complications and reduce mortality, patients at high risk for AKI must be identified early. This study examined the connection between AKI and albumin-corrected anion gap (ACAG) in critically ill AP patients.

This study took into account every eligible patient from the Medical Information Marketplace for Critical Care IV database. The cumulative risk of AKI and in-hospital mortality were calculated using Kaplan-Meier curves. The association between ACAG and AKI was investigated using multivariate Cox regression models and restricted cubic splines (RCS). The robustness of the results was assessed through subgroup analyses.

AKI incidence was 70.87 percent, in-hospital mortality was 13.87%, and the mean ACAG was 20.15 ± 5.64 for the 714 patients that were included. The ACAG‥ 20.25 group had a significantly higher incidence of AKI and a significantly higher risk of needing renal replacement therapy (RRT) (P < 0.001), according to Kaplan–Meier analysis.

Both as a continuous variable (HR: 1.12 [95% CI: 1.04–1.21], P = 0.004) and as a categorical variable (HR: 1.89 [95% CI: 1.11–3.23], P = 0.020), multivariable Cox regression showed that ACAG was independently linked to AKI risk in AP patients. A linear relationship between rising AKI risk and ACAG was validated by restricted cubic spline modeling. Overall, in critically ill patients with AP, elevated ACAG levels (≥20.25 mmol/L) at ICU admission are linked to a high risk of AKI.

Reference:

Wang, Z., Zhang, H., Xie, X., Cao, F., & Li, F. (2025). Albumin-corrected anion gap predicts acute kidney injury in critically ill patients with acute pancreatitis: a retrospective cohort study. BMC Nephrology, 26(1), 348. https://doi.org/10.1186/s12882-025-04293-y