Background: Diagnosing outlet obstruction after IPAA can be challenging because the etiology is multifactorial.
Objective: The aim of this study was to assess possible factors associated with outlet obstruction from paradoxical anal muscle contraction (paradox) after IPAA unrelated to strictures or structural abnormalities.
Design: This was a retrospective study from a prospectively maintained pouch database.
Settings: The study was conducted at a tertiary referral center.
Patients: All of the patients with paradox after ileal J-pouch-anal anastomosis verified by anal physiology were identified from our prospectively maintained database. Patients with endoscopic or digital evidence of strictures or other anatomic abnormalities were excluded.
Main outcome measures: Demographic, clinical, and perioperative factors were obtained, including previous abdominal operations, history of pouchitis, need for anal intubation, diagnosis of small-bowel obstruction, and radiologic findings at the time of paradox diagnosis.
Results: There were 40 patients (17 women) with an overall mean age of 39 years (range, 17-60 years) and a mean follow-up of 15 years (range, 1-28 years) after IPAA. Pathologic diagnoses at the time of ileal pouch creation were ulcerative colitis (n = 27), indeterminate colitis (n = 11), Crohn's disease, and familial adenomatous polyposis (1 case each). A total of 15 (37%) of 40 patients were diagnosed with small-bowel obstruction before their paradox diagnosis, 8 of whom underwent surgery, which revealed diffusely dilated small bowel and pouch without intraoperative identification of a transition point. The time from ileal pouch creation to paradox diagnosis was significantly longer in patients receiving a diagnosis of small-bowel obstruction than in the remaining paradox patients (7.2 vs 2.6 years; p < 0.001).
Limitations: This study was limited by its nonrandomized retrospective nature.
Conclusions: After an IPAA, patients with outlet obstruction from paradox can appear to have a small-bowel obstruction. A high incidence of suspicion is needed to make the correct diagnosis and avoid an unneeded laparotomy.