C-Reactive Protein and Procalcitonin Are Predictors of the Severity of Acute Appendicitis in Children

Objective The aim of this study was to evaluate the use of procalcitonin (PCT) and C-reactive protein (CRP) on admission as predictors of the severity of appendicitis in children. Methods We prospectively studied 111 consecutive patients admitted with a diagnosis of acute appendicitis between July 2009 and February 2010 and recorded the following variables: age, sex, time since diagnosis, laboratory data, complications (abscess, intestinal obstruction), presence of hemodynamic instability, mortality, length of stay, and need for admission to the pediatric intensive care unit. Patients were divided into 2 groups according to the diagnosis confirmed during surgery (group 1, appendicitis; group 2, localized or generalized peritonitis). Results Group 1 comprised 69 patients, and group 2 comprised 42 patients. Procalcitonin and CRP values were significantly lower in group 1 than in group 2 (0.15 vs 4.95 ng/mL [P < 0.001] and 3 vs 14.3 mg/dL [P < 0.001]). For a diagnosis of peritonitis, a PCT cutoff of 0.18 ng/mL gave a sensitivity of 97%, specificity of 80%, positive predictive value of 72%, and negative predictive value of 89.3%. The equivalent values for a CRP cutoff of 3 mg/dL were 95%, 74%, 68%, and 96.2%. Complications and the need for admission to the pediatric intensive care unit were more common in patients with peritonitis. Conclusions On admission, CRP and PCT predict the outcome of pediatric patients with appendicitis. Children with CRP greater than 3 mg/dL and/or PCT greater than 0.18 ng/mL have a greater risk of complications; thus, intervention should be early, and patients should be monitored closely.