Ultrasound features of secondary appendicitis in pediatric patients

Abstract

PurposeThe purpose of this study was to evaluate the ultrasonographic findings of secondary appendicitis (SA) and to discuss the differential findings compared with primary appendicitis.MethodsIn this study, we analyzed the ultrasonographic findings of 94 patients under 15 years old of age treated at our institution from May 2005 to May 2014 who had bowel inflammation and an inflamed appendix with a maximal outer diameter >6 mm that improved with nonsurgical treatment (the SA group). Ninety-nine patients with pathologically proven acute appendicitis (the primary appendicitis [PA] group) from June 2013 to May 2014 and 44 patients with pathologically negative appendectomy results from May 2005 to May 2014 were also included to compare the ultrasonographic features of these conditions. A retrospective review of the ultrasonographic findings was performed by two radiologists. The clinical and laboratory findings were also reviewed. The results were statically analyzed using analysis of variance, the Pearson chi-square test, and the two-tailed Fisher exact test.ResultsCompared with PA, cases of SA had a smaller diameter (9.8 mm vs. 6.6 mm, P<0.001), and were less likely to show periappendiceal fat inflammation (98% vs. 6%, P<0.001) or an appendicolith (34% vs. 11%, P<0.001). SA showed mural hyperemia on color Doppler ultrasonography as frequently as PA (P=0.887).ConclusionThe ultrasonographic features of SA included an increased diameter compared to a healthy appendix and the same level of hyperemia as in PA. However, the diameter was commonly in the equivocal range (mean diameter, 6.6 mm), and periappendiceal fat inflammation was rarely present in SA.

EFSUMB Position Paper: Recommendations for Gastrointestinal Ultrasound (GIUS) in Acute Appendicitis and Diverticulitis

“…Soon after introducing ultrasound as a preoperative tool, cases of "spontaneously resolving appendicitis" were observed [56,57]. Recent research confirms mild forms of appendicitis, which resolve spontaneously or under antibiotic therapy [4,58,59]. Strictly speaking they are not false-positive, but rather mild courses that probably would not require surgery.…”

Comparison of Clinical Characteristics According to the Existence of Secondary appendicitis in Pediatric Acute Gastroenteritis: A Retrospective Single Center study

“…Whereas cecal wall thickening is local, asymmetrical, and irregular in primary appendicitis, it is symmetrical, and regular in secondary appendicitis. (3,17) Appendiceal distention can be observed in both cases; however, appendiceal wall thickening and periappendiceal fat deposition are characteristic ndings of primary appendicitis. (12) Color Doppler imaging shows increased blood ow in the thickened appendiceal wall in primary appendicitis, while hyperemia of terminal ileum is characteristic of secondary appendicitis.…”

“…Although acute gastroenteritis is relatively common in children, the clinical features and prognosis of acute gastroenteritis according to the presence of secondary appendicitis have rarely been studied or reported. (2,3) Whether the two disease entities should be classi ed into a single category or should be considered independent categories with distinct treatment approaches remains controversial. Therefore, in the present study, we compared the clinical features and courses of acute gastroenteritis according to the presence of secondary appendicitis.…”

Useful Ultrasound Findings of Pediatric Patients with Equivocal Results of Appendicitis: Analysis Based on a Structured Report Form

“…The patients with increased vascularity of the appendiceal wall had slightly lower false-positives rate (39.3%, 11/28) than those with peri-appendiceal fat infiltration; of these 11 patients, five were considered to have secondary appendicitis due to inflammation of the adjacent organs including enterocolitis (n = 4) and right acute pyelonephritis (n = 1). This is explained by a previous report indicating that mural hyperemia is effective to distinguish between appendicitis and the normal appendix, but not between primary and secondary appendicitis (18). The remaining six patients had no specific diagnosis and some of them may have true appendicitis since spontaneous resolution of simple appendicitis can occur (19).…”