Differentiating acute appendicitis from other causes of acute abdominal pain in children frequently remains unsatisfactory. To determine whether initial historical and physical examination findings might predict final diagnoses, 246 patients with complaints of nontraumatic and nonrecurrent acute abdominal pain were studied. All were between three and 18 years of age and had presented to a hospital-based pediatric emergency department. Each family was telephoned an average of 5.1 days after the visit to determine the patient's subsequent clinical course; operative notes and pathology reports were reviewed for patients receiving surgery.
Of these patients with acute abdominal pain, both fever and vomiting were present in 18 of the 24 who eventually had diagnoses of appendicitis, compared with 49 of 222 patients with other final diagnoses (P > 0.01, with negative predictive value 0.97, sensitivity 0.75, and specificity 0.78, but positive predictive value only 0.27). The duration of the pain at presentation and the frequency of other symptoms (eg, diarrhea, dysuria, anorexia, and lethargy) were unrelated, however, to final diagnosis, as was the duration of the pain and whether abdominal tenderness initially was localized or generalized. Nonruptured appendicitis was generally indistinguishable from ruptured appendicitis preoperatively, by both duration and symptoms. Boys were found more likely to have appendicitis (with or without rupture) than girls (18/118 or 15%, vs. 6/128 or 5%, P > 0.05).
In conclusion, fever and vomiting were noted at presentation more frequently in children with appendicitis than in children with other causes of acute abdominal pain. Other initial historical and physical examination findings were noted with almost the same frequency in acute abdominal pain patients both with and without appendicitis.