Localized Eosinophilic Ileitis Presenting As Refractory Pediatric Intestinal Pseudo-Obstruction With Recurrent Ileostomy Prolapse: A Delayed Histopathologic Diagnosis.

Pediatric intestinal pseudo-obstruction (PIPO) is a rare, severe gastrointestinal motility disorder characterized by recurrent symptoms of bowel obstruction in the absence of a mechanical cause. Although most pediatric cases are attributed to primary neuromuscular abnormalities, secondary inflammatory disorders should be considered when symptoms are progressive, refractory to conventional therapy, or associated with peripheral eosinophilia and atopic disease. Localized eosinophilic ileitis is an uncommon manifestation of eosinophilic gastrointestinal disease (EGID) and rarely presents as secondary PIPO, making diagnosis particularly challenging. We describe a four-year-old Hispanic boy with a history of egg allergy, atopic dermatitis, lactose intolerance, chronic constipation, progressive abdominal distension, anemia, and peripheral eosinophilia who developed recurrent intestinal pseudo-obstruction beginning at two years of age. Hirschsprung disease was excluded by both rectal suction biopsy and subsequent full-thickness rectal biopsy, each demonstrating normal ganglion cells. Persistent symptoms despite maximal medical therapy prompted creation of an end ileostomy for bowel decompression, which required conversion to a loop ileostomy after early prolapse. During the following two years, the patient experienced recurrent ileostomy prolapse requiring multiple operative revisions. Previous surgical specimens demonstrated ischemic and inflammatory changes without eosinophilic infiltration. Because of persistent obstructive symptoms and recurrent prolapse, definitive ileostomy reversal was performed. Intraoperatively, the prolapsed ileal segment appeared erythematous, mildly thickened, and friable, while the remaining bowel appeared grossly normal. Histopathologic examination of the resected specimen demonstrated focal patchy intramucosal eosinophilia exceeding 70 eosinophils per high-power field, establishing the diagnosis of localized eosinophilic ileitis after exclusion of secondary infectious causes. No eosinophilic infiltration had been identified in previous rectal or ileostomy specimens. The patient experienced rapid postoperative recovery and remains asymptomatic 12 months after surgery without recurrent pseudo-obstruction or prolapse. This case highlights the diagnostic challenges posed by localized eosinophilic ileitis, demonstrates the limitations of negative biopsies obtained from uninvolved bowel, and emphasizes the importance of considering EGID in children with refractory intestinal dysmotility, peripheral eosinophilia, and atopic disease.