A 48-hour Symptom Threshold Predicts Perforated Appendicitis: Development of a Clinical Risk Model

Predicting the likelihood of perforation in acute appendicitis at the time of hospital admission is essential for guiding treatment strategies. This study assesses the impact of time from symptom onset to hospital presentation on the risk of perforation and incorporates these findings into a predictive model.

This retrospective study analyzed the occurrence of perforation in patients who underwent appendectomy for acute appendicitis. The patients were categorized into six groups based on the duration from symptom onset to hospital presentation: less than 12, 12-24, 24-48, 48-72, 72-96, and more than 96 h.

Data from 414 patients across two hospitals revealed that most patients presented within 12-24 h (125 cases), followed by the 24-48 h group (121 cases). The risk of perforated appendicitis increased with longer time intervals (p < 0.01). Receiver operating characteristic (ROC) analysis demonstrated good predictive accuracy of the time intervals for perforation (area under the curve (AUC) 0.76, 95% confidence interval (CI) 0.71-0.82). A time interval of 48 h or more was found to be an independent risk factor for perforation (adjusted odds ratio (adj OR) = 3.30, 95% CI: 1.54-6.21). Elevated CRP levels (adj OR = 5.12, 95% CI: 2.97-8.73) and the presence of appendicolith (adj OR = 2.38, 95% CI: 1.47-3.83) were also associated with increased risk.

A 48-h interval from symptom onset is a useful cutoff for predicting perforation in acute appendicitis. A predictive model incorporating the 48-h time lapse, C-reactive protein (CRP) levels, and presence of appendicolith is proposed.