Labs Do Not Predict Postoperative Intra-abdominal Abscess in Pediatric Perforated Appendicitis

Introduction: We aim to evaluate the utility of postoperative labs in predicting the devel-opment of an intra-abdominal abscess (IAA) in pediatric patients with perforated appen-dicitis. We hypothesize that postoperative labs are not predictive of IAA development. Methods: This was a single-institution retrospective cohort study that included pediatric patients (n = 61) who underwent surgery for perforated appendicitis from January 1, 2019 to December 1, 2020. Patients were stratified into those who developed a postoperative IAA (n = 22) and those who did not (n = 39). Postoperative labs (white blood cell [WBC] count, absolute neutrophil count, platelet count, C-reactive protein) were examined. Mann-Whitney U tests and chi-square tests were used to assess for differences between groups. Results: There was extensive heterogeneity and overlap in postoperative lab values be-tween patients who developed an IAA and those who did not. Almost all patients who developed an IAA had clinical signs that were indicative of abscess formation regardless of their postoperative WBC count or change in WBC count. While patients who developed an IAA had a higher postoperative median WBC count (10.8 versus 8.4, P = 0.003) and a smaller WBC count decrease (-4.9 versus-7.4, P = 0.01), no cutoff value for any of the examined lab values specifically predicted abscess formation. Postoperative median absolute neutrophil count (7.4 versus 4.0, P = 0.15), platelet count (360 versus 353, P = 0.98), and C-reactive protein (8.20 versus 5.32, P = 0.06) did not differ significantly. Conclusions: We conclude that postoperative labs have limited clinical utility in evaluating IAA development in children with perforated appendicitis. (c) 2022 Elsevier Inc. All rights reserved.

Automated summary

This study aimed to evaluate the predictive value of postoperative labs in intra-abdominal abscess (IAA) development in pediatric patients with perforated appendicitis. The results showed extensive heterogeneity and overlap in postoperative lab values between patients with and without IAA. Clinical signs were more indicative of abscess formation than postoperative lab results. Although patients with IAA had higher postoperative WBC counts and smaller decreases in WBC count, no specific cutoff value for any examined lab value predicted abscess formation. Therefore, postoperative labs have limited clinical utility in evaluating IAA development in children with perforated appendicitis.