Original article
Prospective Validation of the Pediatric Appendicitis Score

https://doi.org/10.1016/j.jpeds.2008.01.033Get rights and content

Objective

To prospectively validate the Pediatric Appendicitis Score (PAS), developed on a cohort of children with abdominal pain suggestive of appendicitis, in unselected children with abdominal pain who present to the emergency department.

Study design

Over a 19-month period, we prospectively recruited children 1 to 17 years old who came to our tertiary pediatric emergency department, with a chief complaint of abdominal pain of duration less than 7 days. PAS components included fever >38° C, anorexia, nausea/vomiting, cough/percussion/hopping tenderness (2 points), right-lower-quadrant tenderness (2 points), migration of pain, leukocytosis >10 000 cells/mm3, and polymorphonuclear neutrophilia > 7500 cells/mm3. A follow-up call was made to verify final outcome. Sensitivity, specificity, and the receiver operating characteristic curve of the PAS with respect to diagnosis of appendicitis were calculated.

Results

We collected data on 849 children. 123 (14.5%) had pathologic study–proven appendicitis. Mean (median, range) score for children with appendicitis and without appendicitis was 7.0 (7, 2-10) and 1.9 (1, 0-9), respectively. If a cutoff PAS of ≤2 was used to discharge patients without further investigation, only 3 (2.4%) with appendicitis would be sent home. If a PAS of ≥7 was used to take children to the operating room without further investigation, only 29 (4%) would not have appendicitis. For the PAS the area under the receiver operator curve was 0.95.

Conclusions

The PAS is useful, because a value ≤2 (found in 73% of children without appendicitis) has high validity for ruling out appendicitis, and a score ≥7 (found in 61% of children with appendicitis) has a high validity for predicting the presence of appendicitis. Children with PAS of 3 to 6 (37% with appendicitis and 23% without appendicitis in this study) should undergo further investigation such as observation, ultrasonography, or computed tomography.

Section snippets

Methods

The study was approved by the Hospital for Sick Children Research Ethics Board. Between September 1, 2003, and March 31, 2005, we prospectively recruited children 1 to 17 years old who came to our tertiary urban pediatric emergency department in Toronto, Ontario, Canada, with a chief complaint of abdominal pain of less than 7 days duration. Our emergency department census is 50,000 children a year, with 24hour coverage by a pediatric emergency medicine staff and an in-hospital pediatric surgery

Results

A total of 1060 patients were approached to participate in the study, and 849 (80%) children 1 to 17 years old were recruited to the study and fulfilled the inclusion and exclusion criteria. We had no study attrition; all patients for whom consent was obtained were included in the study. A total of 123 patients (14.5%) had pathology-proven appendicitis. Comparison between the study group and the control group are presented in Table I. The mean (median, SD, range) score for children with

Discussion

We found PAS score24 to be valid for the diagnosis of appendicitis when the PAS was 7 or greater, and for the exclusion of appendicitis when the PAS was 2 or under. For children who have a PAS between 3 and 6, the score cannot accurately determine the diagnosis. This is the group in which further investigation using imaging studies is needed (Figure 1).

Several scoring systems have been suggested previously in the literature,12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 most in adults. In a

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      Citation Excerpt :

      Notably, WBC was the most commonly reported laboratory test (10 studies) followed by ANC or percentage of neutrophils [28-30] (seven studies). The most commonly reported cutoff for WBC is 10,000 cells/mm3 (in nine studies), while the cutoff for ANC varied somewhat among studies: 7500 cells/mm3 in three studies [19,23,26] and 6750 cells/mm3 in one [31]. Our study confirms these cutoff points and the strong association between low ANC and the absence of appendicitis among patients with signs and symptoms suggestive of appendicitis found in previous studies [32].

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