Evaluating Pouch Problems

Introduction and Classification of Complications of Ileal Pouch

Approximately 20% to 30% of patients with ulcerative colitis (UC) eventually require surgery for failure of medical therapy or development of neoplasia. Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA), initially described in 1978, has become the surgical treatment of choice for the majority of patients with UC who require proctocolectomy. Pouch configuration with two (J), three (S), or four (W) loops of small intestine has been performed, and the J pouch has become the most commonly used one. The normal configurations of the J and S pouch are illustrated in Figs. 1 and 2 . The IPAA procedure preserves intestinal continuity, substantially decreases the risk for dysplasia, and improves health-related quality of life. However, adverse sequelae related to the ileal pouch occur frequently. Recognition and proper diagnosis of those conditions are key for maintaining a healthy pouch and prolonging pouch survival.

Early complications are common after restorative proctocolectomy. The most frequent are bowel obstruction, pouch bleeding, pelvic and wound sepsis. Late complications include stricture of the anastomosis, fistula and abscess, reduced fertility, and pouchitis. Of these complications, pouchitis is the most frequent. The majority of nonmechanical pouch-related complications can be addressed without surgical intervention. However, pouch failure does occur. Pouch failure is defined as the need for permanent diversion, with or without pouch excision or revision. The reported cumulative incidence of pouch failure ranged from 4% to 10%. A metaanalysis of 43 studies of 9317 patients showed that pouch failure rate after IPAA increases proportionally to the length of follow-up: from 6.8% with a median follow-up period of 37 months to 8.5% after more than 60 months. The most common causes for pouch failure are pelvic sepsis, chronic refractory pouchitis, Crohn disease (CD) of the pouch, and pouch fistula or sinus.

Based on published studies as well as the authors’ clinical experience in the unique subspecialty Pouchitis Clinic at the Cleveland Clinic, the authors proposed a classification system of pouch-related complications in 2008 ( Box 1 ). The complications are classified into mechanical, inflammatory, functional, neoplastic, and metabolic conditions related to the pouch by suspected underlying pathophysiologic condition. In this article, the authors provide an update for evaluation of ileal pouch disorders.

Box 1

Surgical and mechanical

∘ Anastomotic leaks

∘ Pelvic/perianal sepsis and abscess

∘ Pouch sinuses

∘ Pouch fistulae

∘ Strictures

∘ Afferent limb and efferent limb syndromes

∘ Infertility and sexual dysfunction

∘ Portal vein system thrombi

∘ Pouch prolapse, twisted pouch, pouch bleeding, sphincter injury or dysfunction, pouchocele

Inflammatory and infectious

∘ Pouchitis

∘ Cuffitis

∘ Crohn disease of the pouch

∘ Proximal small bowel bacterial overgrowth

∘ Inflammatory polyps

Functional

∘ Irritable pouch syndrome

∘ Anismus

∘ Pseudoobstruction or megapouch

∘ “Pouchalgia fugax”

Dysplastic and neoplastic

∘ Dysplasia or adenocarcinoma of the pouch or anal transitional zone

∘ Squamous cell cancer at the anal transitional zone

∘ Lymphoma

Systemic and metabolic

∘ Anemia from chronic disease or iron or vitamin B ₁₂deficiency

∘ Bone loss

∘ Vitamin D deficiency

∘ Nephrolithiasis

∘ Celiac disease

Classification of ileal pouch disorders and associated complications

Surgical and Mechanical Complications

Surgical or mechanical complications are those adverse sequelae that are caused mainly by factors related to the surgery; these include anastomotic leaks, pelvic sepsis and abscess, pouch sinuses and fistulae, strictures, afferent limb syndrome and efferent limb syndrome, infertility, portal vein thrombi, pouch prolapse, and pouch twist. Anastomotic leak is defined as anastomotic separation leading to exodus of pouch luminal content. The most common location of an anastomotic leak is at the pouch-anal anastomosis followed by the tip of the “J”, and the body of the pouch along the staple line ( Fig. 3 ). Pelvic sepsis is defined as any infective process present in the peripouch area or at the true pelvis distal to the pelvic inlet, whereas pelvic abscess is a collection of purulent exudates without demonstrable anastomotic leaks. Pouch sinus, which is typically a later presentation of an initial anastomotic leak, is defined as a blind tract that may lead to abscess cavity ( Fig. 4 ). Pouch fistula ( Fig. 5 ) is defined as an abnormal passage from one epithelial surface (ie, the ileal pouch) to another epithelial surface (eg, vagina, bladder, or skin). Afferent limb syndrome is defined as distal small bowel obstruction caused by an acute angulation, prolapse, or intussusceptions of the afferent limb at the junction to the pouch ( Fig. 6 ). Efferent limb syndrome typically occurs in patients with an S pouch with a dysfunctional or excessively long efferent limb, which partially obstructs the outlet of the pouch ( Fig. 7 ). Other surgery-related complications include pouchocele and pouch mucosal or full-thickness prolapse ( Fig. 8 ), anal sphincter injury or dysfunction, adhesions, small bowel obstruction, pouch and small bowel herniation or intussusceptions, twisted pouch, and incisional hernia.