[Appendicitis predictive score for children younger than 4 years]

Introduction: The clinical presentation of acute appendicitis in infants and young children is nonspecific. The diagnosis is often delayed and is accompanied by high rates of appendiceal perforation. The aim of the present study was to develop an early diagnostic scale for acute appendicitis in children less than 4 years of age. Results: The scale had a high discrimination index area under the ROC curve of 0.96 (95%CI 0.88-0.99), sensitivity of 95.1% (95%CI 86.3-99.0%), specificity of 90.0% (95%CI 55.7-89.5%), positive predictive value of 98.3% (95%CI 90.0-99.7%) and negative predictive value of 75.0% (95%CI 49.4-90.2). Conclusions: In this study, a risk score based on characteristics of children less than 4 years with abdominal pain was developed that may help predict a patient’s risk of developing acute appendicitis. Patients and methods: 100 children less than 4 years of age with a presumptive diagnosis of acute appendicitis were retrospectively evaluated in 4 hospitals. The case group comprised 90 patients with histopathological diagnosis of positive appendicitis (with inflammation in the appendiceal wall) while the control group comprised 10 patients with a histopathological diagnosis of negative appendicitis (without inflammation). Epidemiological, clinical, laboratory, and ultrasound variables were screened using Least Absolute Shrinkage and Selection Operator (LASSO) and logistic regression to construct a predictive risk score. Accuracy of the score was measured by the area under the receiver operating characteristic curve. Final model comprised 4 variables (Blumberg's sign, C-reactive protein, neutrophil-lymphocyte index and positive ultrasound). Results: The scale had a high discrimination index area under the ROC curve of 0.96 (95%CI 0.88-0.99), sensitivity of 95.1% (95%CI 86.3-99.0%), specificity of 90.0% (95%CI 55.7-89.5%), positive predictive value of 98.3% (95%CI 90.0-99.7%) and negative predictive value of 75.0% (95%CI 49.4-90.2). Conclusions: In this study, a risk score based on characteristics of children less than 4 years with abdominal pain was developed that may help predict a patient’s risk of developing acute appendicitis.