Image of the Month
A 17-year-old white male presented with a 4-day history of sharp, right lower quadrant (RLQ) abdominal pain, nausea, and vomiting. Findings from physical examination showed diffuse abdominal tenderness with guarding of the RLQ region. White blood cell counts with differential and liver enzymes were normal. Computed tomography of the abdomen was unremarkable. Because of worsening RLQ pain, he underwent laparoscopic appendectomy. The appendix was grossly normal; pathology is shown in Figure 1.
What is the most likely cause of appendicitis in this patient: (1) Fecolith, (2) Crohn disease, (3) Trichuris trichuria, or (4) Enterobius vermicularis?
Figure 1A shows mucosal inflammation with prominent eosinophils. E vermicularis was identified in the appendiceal lumen histologically; this organism is characterized by a prominent esophageal bulb and external spines called lateral alae (Fig. 1B). Although appendicitis is a common surgical disease in pediatric patients, parasites are rarely found associated with appendiceal inflammation. E vermicularis is the most common helminth responsible for appendicitis in children (1). Infestation of the appendix can produce clinical features of appendiceal colic (2). In a large pediatric series of 1549 appendectomies, E vermicularis was found in the appendix of 21 patients (1.4%) (3). Because appendectomy alone is not curative, the patient was treated with mebendazole and rapidly recovered. In summary, appendectomy specimens should be reviewed for the presence of eosinophilic infiltration and parasitic infection because pharmacologic eradication with antihelminthics is necessary in such cases following surgery (3).
The authors report no conflicts of interest.
Submissions for the Image of the Month should include high-quality TIF endoscopic images of unusual or informative findings. In addition, 1 or 2 other associated photographs, such as radiological or pathological images, can be submitted. A brief description of no more than 200 words should accompany the images. Submissions are to be made online at www.jpgn.org, and will undergo peer review by members of the NASPGHAN Endoscopy and Procedures Committee, as well as by the Journal.
1. da Silva DF, da Silva RJ, da Silva MG, et al
. Parasitic infection of the appendix as a cause of acute appendicitis. Parasitol Res 2007; 102:99–102.
2. Budd JS, Armstrong C. Role of enterobius vermicularis causing symptoms of appendicitis. Br J Surg 1987; 74:748–749.
3. Arca M, Gates R, Groner J. Clinical manifestations of appendiceal pinworms in children: an institutional experience and a review of the literature. Pediatr Surg Int 2004; 20:372–375.