The Predictive Value of Plasma Sodium and Other Laboratory Parameters in Determining Complicating Appendicitis in Children

Abstract

Objective: Finding a reliable preoperative predictor of complicated acute appendicitis (AA) has been a challenging diagnostic problem. The present study aimed to identify potential factors that may predict complicated AA in the pediatric emergency department (ED) based on routine, widely available laboratory tests on admission to the ED, including plasma sodium concentration.

Methods: We retrospectively reviewed clinical and laboratory data of pediatric patients with AA who underwent emergency surgery at our department between January 2020 and December 2022. The patients were divided into two groups: histopathologically proven complicated AA (n = 80), and non-complicated AA (n = 155).

Results: Complicated AA was associated with reduced plasma sodium and chloride concentrations (p < 0.001, both), decreased values of lymphocytes (p = 0.002), elevated C-reactive protein (CRP) ( p < 0.001), elevated values of white blood cells (WBC) and neutrophils (p = 0.012 and 0.001, respectively). In binomial logistic regression, increased levels of CRP and WBC, and decreased levels of sodium were predictors of complicated AA. The area under the ROC curve was 0.825 (95% CI 0.764, 0.886).

Conclusion: We identified mild hyponatremia and elevated CRP and WBC values as potential markers for distinguishing complicated from uncomplicated pediatric AA with implications for surgical approaches for treating complicated AA and conservative approaches for treating uncomplicated AA.

Fig. 1.

A flow diagram of the study.

Fig. 2.

Percentage and number of patients with uncomplicated and complicated AA having eunatremia or mild hyponatremia.

Fig. 3.

ROC curve for binomial logistic regression model. ROC, receiver operating characteristic.