Role of Total Calcium and Albumin-Corrected Calcium as Early Predictors of Severe Acute Pancreatitis: A Prospective Observational Study

Abstract

Background: Early identification of patients at risk of developing severe acute pancreatitis (SAP) remains a major clinical challenge. Although several prognostic scoring systems such as Ranson, APACHE-II, BISAP, and Modified CT Severity Index are available, many require multiple clinical variables or imaging studies that are not immediately available at admission. Serum total calcium (TC) and albumin-corrected calcium (ACC) are inexpensive, routinely available biochemical parameters that may facilitate early severity prediction.

Objectives: To evaluate the role of serum total calcium and albumin-corrected calcium as early predictors of severe acute pancreatitis and to compare their predictive performance with disease severity assessed by the Ranson score.

Materials and Methods: A prospective observational study was conducted in the Department of Biochemistry in collaboration with the Department of General Surgery from May 2022 to May 2024. Adult patients diagnosed with acute pancreatitis according to the Revised Atlanta Classification were enrolled consecutively after obtaining informed consent. Serum total calcium and albumin concentrations were measured within 24 hours of hospital admission. Albumin-corrected calcium was calculated using the formula: Corrected Calcium = Total Calcium + 0.8 × (4.0 − Serum Albumin). Disease severity was assessed using the Ranson scoring system. Statistical analysis was performed using SPSS version 26.0. Continuous variables were expressed as mean ± standard deviation, while categorical variables were expressed as frequencies and percentages. One-way ANOVA, Pearson’s correlation analysis, ROC curve analysis, and multivariate regression were used wherever appropriate. A p-value <0.05 was considered statistically significant.

Results: Both total calcium and albumin-corrected calcium showed a significant progressive decline with increasing disease severity. Total calcium demonstrated a stronger inverse correlation with Ranson score than albumin-corrected calcium, while both biomarkers exhibited excellent discriminatory ability for predicting severe acute pancreatitis. Their rapid availability and low cost make them clinically valuable tools for early risk stratification.

Conclusion: Serum total calcium and albumin-corrected calcium are reliable, inexpensive, and readily available early biomarkers for predicting severe acute pancreatitis. Their incorporation into routine admission investigations may facilitate early identification of high-risk patients and timely intensive management, particularly in resource-limited healthcare settings.