Clinical differentiation between acute appendicitis and acute mesenteric lymphadenitis in children.

INTRODUCTION: Acute mesenteric lymphadenitis in children has a clinical presentation very similar to that of acute appendicitis. The aim of this study was to evaluate whether it is possible to clinically differentiate between acute appendicitis and acute mesenteric lymphadenitis in children.

METHODS: A prospective cohort analysis was performed for all children (<17 years) presenting to the emergency department of our institution with acute abdominal pain between June 2005 and July 2006. The relevant clinical parameters, clinical and radiological diagnoses and all management decisions were scored prospectively. Ultrasound was the primary imaging modality for the majority of patients. All patients were re-evaluated until a final diagnosis was attained. The Alvarado score was calculated retrospectively, and a logistic regression model was used to analyze the diagnostic potential of clinical parameters.

RESULTS: 289 patients were eligible for analysis. 38 patients had acute mesenteric lymphadenitis, and 69 patients had acute appendicitis as a final diagnosis. The positive predictive values of the clinical diagnosis, the Alvarado score and the logistic regression model were 0.62, 0.81 and 0.79 respectively. Ultrasound had a positive predictive value of 96% for acute appendicitis.

CONCLUSION: It is not possible to accurately distinguish acute mesenteric lymphadenitis from acute appendicitis in children using clinical evaluation alone. Ultrasound should be performed in equivocal cases.