Purpose: The distinction between perforated and non-perforated appendicitis in pediatric patients is beginning to be clinically relevant as a deciding factor of whether to surgically intervene on a pediatric patient or not. Perforation is treated in some institutions conservatively initially while non-perforated appendicitis would require an emergent surgery. While CT scans have proven to be an excellent imaging modality for differentiating perforated from non-perforated appendicitis they are associated with exposure of pediatric patients to ionizing radiation, which carries a potential for future cancer. On a previous study performed in our institution a scoring system (table 1) that incorporates clinical, laboratory, and ultrasound findings was developed and demonstrated high accuracy [1]. We therefore performed a retrospective study to validate this scoring system.
Methods: After receiving Institutional Board Review approval, we conducted a search on our Picture Archiving Communication System (PACS) and reviewed all pediatric patients (age 0-21 years) with acute appendicitis diagnosed by ultrasound, from June 2015 through June 2019. For these patients, the clinical (maximum temperature, days of fever, days of pain, age, presence of vomiting/diarrhea) laboratory (WBC, CRP, and ESR), and ultrasound findings (appendix size, loss of submucosal layer, complex free fluid, amount of echogenic fat, and abscess) were recorded. This data was placed into the scoring system and compared to the gold standard, surgical and pathological evaluation. We excluded patients with equivocal scores who were missing data parameters that would increase their score to be consistent with perforation. Sensitivity, specificity, positive predictive values, and negative predictive values were calculated.
Results: Of the 143 patients who met enrollment criteria, 92 were males and 51 females ranging from 5 weeks to 19 years of age. 72 (50%) were deemed perforated by the scoring system with 53 (37%) actually perforated. When compared to surgical/pathological results the scoring system demonstrated the following results: Sensitivity=0.93, specificity= 0.78, PPV= 0.74, and NPV=0.94.
Conclusions: this study validates a scoring system based on clinical, laboratory and sonographic findings, for differentiation of perforated from non- perforated appendicitis in pediatric patients, with good results.
References:
Blumfield E, Yang D, Grossman J. Scoring system for differentiating perforated
and non-perforated pediatric appendicitis. Emerg Radiol. 2017 Oct;24(5):547-554.
doi: 10.1007/s10140-017-1535-1. Epub 2017 Jul 7.
