Neurogenic appendicopathy: clinical, macroscopic, and histopathological presentation in pediatric patients

The proliferation of nerve fibers in the appendix, in association with an increase of the neuropeptides such as vasoactive intestinal peptide and substance P characterizes neurogenic appendicopathy (NA), which may mimic the symptoms of acute appendicitis (AA). It may be difficult to differentiate this little known distinct pathological entity clinically from AA. The aim of this study is to describe the epidemiology, clinical signs, and histological description of NA in pediatric patients.

After institutional review board approval, all appendiceal specimens from children who underwent appendectomy between February 2006 and December 2008 were analyzed. Analysis included age, gender, clinical symptoms, blood tests, intraoperative macroscopic assessment of the appendix, and the histopathological type of NA. NA was diagnosed by hematoxylin-eosin staining and /or S-100 immunochemistry and then classified into different histopathological groups.

Of the 385 appendix specimens examined, 29 (7.5%) met the histopathological criteria of NA. The median duration of abdominal pain was 2 days (range, 1 to 7). The surgeon characterized the appendix as follows: not inflamed in 5 (17.2%), acute in 17 (58.6%), phlegmonous in 4 (13.8%), and perforated in 3 patients (10.4%). Histopathological diagnosis of NA classified the specimen as axial neuroma in 2 (7%), mucosal in 12 (41%), and submucosal in 15 cases (52%).

NA is a relatively common diagnosis in children. NA must be considered in patients with recurrent right lower quadrant pain or signs of AA, even if intraoperative findings are normal. For these patients, we recommend appendectomy and consideration of a subsequent histopathological workup.