Disclosure History of the Procedure: Historically, surgery has been viewed as definitive therapy for ulcerative colitis (UC). Total proctocolectomy is often curative, alleviating symptoms and removing the risk of colonic adenocarcinoma. (Whereas, total proctocolectomy is palliative in patients with Crohn disease [CD] and pancolitis.) Prior to 1980, total proctocolectomy with end ileostomy or continent (or Koch) ileostomy was the mainstay of therapy. However, in the late 1970s reports of continence-preserving procedures involving ileal pouch-anal anastomosis began to surface (Parks, 1978). As experience amassed, the procedure was refined, and the ileal pouch-anal anastomosis has become the most common operation for patients with UC who wish to maintain anal continence. Problem: UC is an inflammatory condition of the colon. It must be differentiated from CD because, although both are inflammatory bowel diseases, each is managed differently by the surgeon (see Crohn Disease: Surgical Perspective). In general, the inflammatory changes in UC involve the rectum and extend proximally in a continuous fashion. The entire colon is involved in severe cases. It is the second most common cause of massive GI bleeding in children. In addition to the colonic involvement, extraintestinal manifestations include those of the eye, skin, and joints and biliary disease. These manifestations underscore the systemic nature of the inflammatory process. The disease has a chronic course, in which exacerbations are followed by periods of remission. Total proctocolectomy is curative; thus, it is the standard surgical treatment. Frequency: About 1 million Americans are affected with UC (Hunt, 2000). The incidence is higher in the northern hemisphere, with an incidence of 4-6 cases per 100,000 people in the United States, United Kingdom, and Scandinavia (Garland, 1982; Cotran, 1998). Two of every 100,000 children are affected, and 20-25% of all cases of UC occur in persons aged 20 years or younger. UC is more common in whites than in blacks, and it tends to occur in families; disease concordance is documented in monozygotic twins (Lindberg, 1992). Etiology: The etiology of UC is unknown. The cause appears to be multifactorial, and follows a nonmendelian pattern, which suggests that more than one allele is involved (Hunt, 2000). Environmental factors also play a role. For example, sulfate-reducing bacteria, which produce sulfides, are found in large numbers, and sulfide production is higher in patients with UC than in other people. Sulfide production is even higher in patients with active UC than in patients in remission (Levine, 1998). Nonsteroidal anti-inflammatory drug (NSAID) use is higher in patients with UC than in control subjects, and one third of patients with an exacerbation of UC report recent NSAID use. This finding leads some to recommend avoidance of NSAID use in patients with UC (Felder, 2000). Vitamins A and E, both considered antioxidants, are found in low levels in as many as 16% of children with UC exacerbation (Bousvaros, 1998). Chromosomes are thought to be less stable in patients with UC, as measured with telomeric associations in peripheral leukocytes (Cottliar, 2000). This phenomenon also may contribute to their increased cancer risk. Whether these abnormalities are the cause or the result of the intense systemic inflammatory response in UC is unresolved. An autoimmune phenomenon has been suggested as one possible etiologic factor in UC. The presence of antineutrophil cytoplasmic antibodies (ANCA) and anti–Saccharomyces cerevisiae antibodies (ASCA) is a well-known feature of inflammatory bowel disease (Vasiliauskas, 1997; Peeters, 2000; Dubinsky, 2001; Hoffenberg, 1999; Kaditis, 1998). In addition, an immune modulatory abnormality has been assumed to be responsible for the lower incidence of UC in patients who have undergone previous appendectomy. The incidence of previous appendectomy is lower in UC patients with UC (4.5%) than in control subjects (19%), and a further protective effect appears to exist if the appendectomy was performed before the patient was aged 20 years (Duggan, 1998). Also, patients in whom appendectomy was performed for inflammatory disorders (eg, appendicitis or mesenteric adenitis) seem to have a lower incidence of UC than patients who undergo appendectomy for other disorders such as nonspecific abdominal pain (Andersson, 2001). Psychological and psychosocial stress factors can play a role in the presentation of UC and precipitate exacerbations of UC (Levenstein, 2000). Pathophysiology: UC manifests as an intense inflammatory reaction in the large intestine. It involves the rectum and extends proximally to involve the entire colon (pancolitis) in severe cases. The terminal ileum is not primarily involved, but it may be secondarily inflamed because of backwash ileitis, or the reflux of noxious inflammatory mediators from the colon, in as many as 10% of patients (Heuschen, 2001; Kaufman, 1997). Differentiation between UC and CD is critical to developing a treatment plan. Grossly, CD is characteristically noncontiguous, with intervening, or skipped, areas of normal mucosa. The ulcerations in CD tend to be linear and often lead to the classic cobblestone appearance to the mucosa. CD may involve the entire GI tract, while UC involves only the large bowel. Microscopically, the inflammation in both can appear the same, but noncaseating granulomas are present only in CD. Granulomas are present in 60% of CD specimens, but in 0% of UC specimens; therefore, their presence is specific for CD (Kaufman, 1997; Cucchiara, 1999). The inflammation of CD may be transmural, whereas it is confined to the mucosa and submucosa in UC.
Recently, the traditional idea that UC involves only the large bowel has been challenged. Significant gastroduodenal inflammation in children with UC has been reported. Aphthous ulceration, however, is considered unique to CD (Kaufman, 1997). In addition, patchiness of the colonic mucosa suggestive of skip lesions may occur during the treatment phase of UC, leading one to question the diagnosis. These patchy areas may be seen endoscopically in as many as 38% of patients with UC who undergo medical therapy. Rectal sparing also may occur at some point during medical treatment of UC in as many as 44% of cases (Kim, 1999). Clinical: UC presents with cramplike abdominal pain, bloody diarrhea, and tenesmus. Some cases may present with a fulminant course marked by severe diarrhea, fever, leukocytosis, and abdominal distention. Fulminant disease occurs in children more often than adults (Falcone, 2000). An estimated 15% of patients present with an attack severe enough to require hospitalization and steroid therapy (Lichtiger, 1994; Rowe, 2000). Children also may present with systemic complaints, including fatigue, arthritis, failure to gain weight, and delayed puberty. The differential diagnosis of these symptoms in the pediatric population includes many entities, and definitive diagnosis may be delayed (Hoffenberg, 1999).
UC is associated with a variety of extracolonic manifestations. Primary sclerosing cholangitis (PSC) is a potentially severe associated condition, often resulting in cholestatic jaundice and liver failure that requires transplantation. Of patients with PSC, 75% have inflammatory bowel disease. Of patients with UC, 5% have cholestatic liver disease, and 40% of those have PSC. One interesting hypothesis about the etiology of PSC in patients with UC involves the release of proinflammatory agents in the colon that are absorbed; thus, they enter the enterohepatic circulation and are concentrated in the biliary system, leading to bile duct damage (Cox, 1998; Marchesa, 1997).
Other extraintestinal manifestations include uveitis, pyoderma gangrenosum, pleuritis, erythema nodosum, ankylosing spondylitis, and spondyloarthropathies. Reportedly 6.2% of patients with inflammatory bowel disease have a major extraintestinal manifestation. Uveitis is the most common, with an incidence of 3.8%, followed by PSC at 3%, ankylosing spondylitis at 2.7%, erythema nodosum at 1.9%, and pyoderma gangrenosum at 1.2% (Bernstein, 2001). Reports vary, however, and some have stated that the incidence of ankylosing spondylitis is as high as 10%. Arthropathies occur in as many as 39% of patients with inflammatory bowel disease. About 30% of these have inflammatory back pain, 10% have synovitis, and as many as 40% have radiologic findings of sacroiliitis (deVlam, 2000).
Anecdotal reports of recurrent subcutaneous abscesses unrelated to pyoderma gangrenosum exist (Murata, 1999). Multiple sclerosis also has been weakly associated with UC (Kimura, 2000). Immunobullous disease of the skin has been associated with UC. One theory regarding this association is the concept of epitope spread. Colonic inflammation leads to mucosal damage, which exposes otherwise hidden antigens. Antibodies to these antigens are then formed; these most likely are cell adhesion molecules, which cross-react with similar antigens in other tissues (Egan, 1999).
Table 1. Ulcerative Colitis vs Crohn Disease Ulcerative Colitis Crohn Disease Colon only involved Pan-intestinal Continuous inflammation extending proximally from rectum Skip-lesions with intervening normal mucosa Inflammation in mucosa and submucosa only Transmural inflammation No granulomas Non-caseating granulomas pANCA positive ASCA positive Bleeding is common Bleeding is uncommon Fistulae are rare Fistulae are common
Indications for surgery in UC are varied. Failure of medical management is the most common indication for surgery. Classically, an acute attack of UC that fails to respond to intravenous steroid therapy within 10 days warrants surgical intervention (Treem, 1995). Steroid dependency is a predictor for the need for surgery and likely a marker for more severe disease.
In addition, the presence of pancolitis is the strongest predictor of the need for surgery in children; more than 80% of patients who require surgery have total colonic involvement (Falcone, 2000). However, during a fulminant attack, the patient's condition is compromised, with a potentially poor nutritional status, low albumin level, low hematocrit level, and complications of high-dose corticosteroid use. As discussed later, the recent surge of cyclosporine use in patients with UC may be useful in inducing remission, providing a window to an improvement in the patient's overall health status prior to surgery and, hence, to minimizing complications. Other indications for surgical intervention include hemorrhage, intolerance to steroid therapy, and growth retardation. One major goal of management in children is the avoidance growth retardation caused by chronic steroid use (Falcone, 2000).
Many physicians use surveillance colonoscopy in following up patients with UC and determining the need for colectomy. This involves scheduled annual or biannual colonoscopy with multiple random biopsies. However, surveillance colonoscopy must be undertaken with caution because even low-grade dysplasia is associated with synchronous adenocarcinoma in as many as 42% of cases, and as many as 84% of neoplasms in UC are missed at random biopsy. Furthermore, 1% of colon cancers in patients with UC have no foci of preexisting dysplasia. Even in patients in whom the disease is medically controlled, the optimal time for colectomy may be 7-10 years after the onset of disease, to prevent colon cancer (Gorfine, 2000).
The risk of developing colon adenocarcinoma must be addressed. Patients with UC have a 1% risk of cancer per year after 8-10 years of disease. After 20 years of disease, the incidence of adenocarcinoma is as high as 25% (Ekbom, 1990). Colonic dysplasia is a precursor to adenocarcinoma, and it occurs in patients with UC. Backwash ileitis is an independent marker for the presence of dysplasia, as is age older than 45 years and the presence of disease for more than 10 years (Heuschen, 2001). Therefore, the patient with UC must be made aware of the significant risk of colon cancer, and surgical intervention in nonacute cases must be encouraged after 10 years of disease.
Table 2. Absolute and Relative Indications for Surgery Indications for urgent surgery in ulcerative colitis Indications for elective surgery in ulcerative colitis Toxic megacolon refractory to medical management Chronic steroid dependency Fulminant attack refractory to medical management Dysplasia or adenocarcinoma found on screening biopsy Uncontrolled colonic bleeding Disease present 7-10 years
Contraindications: Contraindications to ileal pouch-anal procedures in children with UC are few. The only absolute contraindication is anal sphincter dysfunction. Preexisting incontinence due to neurologic impairment or other causes makes reservoir construction unnecessary and makes ileoanal pull-through inadvisable.
Other contraindications include suspected CD. As stressed later, the diagnosis of UC must be certain before an ileal pouch reservoir is created in a patient with inflammatory bowel disease. The need for pelvic radiation also is a contraindication to pelvic reservoir construction. For example, if rectal cancer is found at the time of exploration, end ileostomy should be performed in anticipation of postoperative pelvic irradiation. Radiation leads to pouch fibrosis and noncompliance, with resultant loss of reservoir function. |
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Lab Studies:
Imaging Studies:
Diagnostic Procedures:
Medical therapy: Medical treatment varies depending on the severity of the disease. In mild disease, oral sulfasalazine is effective. Sulfasalazine is 5-aminosalicylate (5-ASA) coupled to a sulfapyridine. It is poorly absorbed in the proximal bowel, and the bacteria in the colon uncouple the 5-ASA from the sulfa moiety, allowing 5-ASA to exert its anti-inflammatory effect on the colonic mucosa by inhibiting prostaglandin synthesis. Topical application of 5-ASA to the rectum by using suppositories or enema, as well as the use of hydrocortisone foam or enemas, also may be effective in mild disease confined to the rectum or left side of the colon. For more severe disease, oral prednisone is used. Intravenous high-dose corticosteroids are used for acute severe exacerbations or fulminant presentations. The recent literature has focused on the use of cyclosporine in acute cases refractory to intravenous corticosteroids. Cyclosporine therapy is indicated in children in whom the disease does not respond to corticosteroid therapy within 7 days of the initiation of treatment. As many as 80% of the cases respond, and emergency colectomy is avoided. Treatment with cyclosporine at doses of 4-8 mg/kg/d (adjusted to maintain serum levels of 150-300 mg/mL) was shown to decrease the erythrocyte sedimentation rate, increase the hematocrit and serum albumin levels, and allow weaning from intravenous corticosteroids (Treem, 1995). Intravenous administration of cyclosporine achieves 10-fold higher concentrations in the colonic tissue, compared with oral administration (Lichtiger, 1994). One study revealed that the level of bandemia on the CBC differential was predictive of the response to cyclosporine therapy (Rowe, 2000). Long-term data about cyclosporine therapy are now available. A retrospective review 5 years after receiving cyclosporine for severe corticosteroid refractory ulcerative colitis, found 72% of patients with an initial response to cyclosporine therapy during an acute exacerbation still had their colons. When 6-mercaptopurine (6-MP) or azathioprine was added to the patients' maintenance regimens, the overall chance of avoiding colectomy went from 40% (cyclosporine alone) to 66% at five years. The value of cyclosporine is in the prevention of emergency colectomy in the nutritionally weakened, corticosteroid-dependent, acutely ill child and in deferring surgery until remission is attained. Cyclosporine, however, is associated with a number of complications. Nephrotoxicity can be avoided with close regulation of serum levels to maintain a therapeutic concentration. Minor complications include elevated levels at liver function testing, herpes exacerbations, thrush, and paresthesias. As with all immunosuppressant therapy, opportunistic infection is a concern. Surgical therapy: The underlying principle to the surgical management of UC is total removal of the colon and rectal mucosa. This is achieved by performing a total proctocolectomy. However, UC tends to occur in young individuals in whom the implications of permanent ileostomy may psychologically damaging. Therefore, over the past 20 years, numerous continence-restoring procedures have evolved. The creation of an ileal pouch-anal anastomosis involves total proctocolectomy, with folding of the distal ileum into a J, S, or W formation to create a fecal reservoir. The anastomosis to the anus preserves continence function involving the internal and external anal sphincters. The S and W configurations have been associated with a failure rate as high as 66% and a need for revision. Conversely, the J configuration is associated with a need for revision in only 1-2% of cases. Reasons for failure with S and W pouches include dilation of the reservoir that leads to stasis and elongation of the spout at the anal anastomosis that leads to stenosis (Fonkalsrud, 1999). These technical points are all but alleviated with the current technique of J pouch construction. Transanal defecation is restored in 88% of children with J pouches, whereas 32% of those with S pouches and 32% of those undergoing straight ileoanal pull-through procedures require revision (Durno, 1998). Although most surgeons do not use the S pouch as the first option (because of its pouchitis rate), the spout created in its construction provide an additional 3-5 cm in length in the entire ileal reservoir, compared with the length of a J pouch. Some still advocate straight ileoanal pull-through anastomosis without reservoir construction. Straight endorectal pull-through causes dilatation and compensation over time so that the pouch develops a reservoir function. In addition, length is generally not a problem with a straight pull-through. Thus, many pediatric surgeons perform this as their primary procedure. Good long-term outcomes and patient satisfaction are reported (Shamberger, 1999). However, others have noted a need for revision of the straight pull-through configuration in 70% of the cases (Fonkalsrud, 1999). Construction of the ileal J pouch-anal anastomosis is described here. However, one should keep in mind that the straight ileoanal pull-through is performed in essentially the same manner and uses less total length of small bowel. Preoperative details: Timing of the surgical intervention is the major preoperative concern in UC. If possible, emergency surgery should be avoided because of the considerations mentioned above. If emergency surgery is indicated, most advocate use of a staged procedure. Initially, emergency total colectomy with end ileostomy is performed to alleviate the major symptoms of the disease, including bleeding and pain, and allows the patient to be weaned from steroids. Later, an ileal pouch-anal anastomosis is created, if the patient desires it, with removal of the remaining rectum. Most advocate leaving the rectum in place during the initial emergency operation to prevent disrupting the pelvic tissue planes to make the subsequent pelvic dissection safer. If the patient has mild disease or disease in remission, total proctocolectomy with the creation of an ileal pouch-anal anastomosis may be performed as the initial definitive procedure. Intraoperative details: A total proctocolectomy is performed through a midline abdominal section. The ileum is divided close to the ileocecal valve with a stapler to save maximal ileal length. The ileal branch of the ileocolic artery is preserved, if possible, to provide optimal blood supply to the distal ileum. The rectum is stapled and divided, within 1 cm proximal to the dentate line. This procedure theoretically preserves the sensory nerve fibers in the anal transition zone that contribute to discrimination between gas and stool. Some refute the importance of retaining this zone, reporting no change in functional outcome when the anal transition zone is removed (Choi, 2000). However, rectal mucosectomy may be performed and the ileum brought through a short seromuscular sleeve of rectum. The dimensions of the pouch depend on the size of the patent. In adolescents, as in adults, a 9-12-cm long pouch is created by folding the distal ileum on itself in a J configuration and by using a linear cutting stapler to place staples longitudinally along the antimesenteric boarder between the two limbs of the J to create a reservoir (see Image 2). Limb lengths of 8-10 cm are used in small children. The bowel at the lower end (ie, curve) of the J is then used to create an anastomosis to the anus with a circular stapling device or sutures. Because of the increased incidence of cancer in patients with UC and PSC complete mucosectomy to the dentate line and creation of a hand-sewn pouch-anal anastomosis has been recommended in these patients (Marchesa, 1997). To ensure a tension-free anastomosis at the anus, a number of techniques may be used to gain length in the small bowel. First, the ligament of Treitz may be opened to allow the proximal jejunum to turn toward the pelvis is a more gradual manner. The peritoneum overlying the small bowel mesentery may be sequentially opened in an orientation perpendicular to the superior mesenteric artery ("stair stepping") to release tension and provide length. Finally, the superior mesenteric artery may be divided just distal to the origin of the first or second arterial arcade. This proximal division preserves distal collateral flow and provides length. The need for fecal diversion after ileal pouch-anal anastomosis is controversial in the adult patients. Usually, the need to operate on young patients is due to the severity of illness. Thus, most surgeons prefer to proximally divert the fecal stream in young patients. During the procedure, the distal vascular arcades of the ileum often are divided to gain length to reach the pelvis; this division predisposes the patient to ischemia. Therefore, many surgeons opt for an end ileostomy or loop ileostomy as the means of diversion. Many use loop ileostomy because of the widely held belief that takedown of a loop ileostomy is technically easier. Recent data refute this assumption. On average, the operating time with loop ileostomy takedown is 54 minutes less than that of end ileostomy. However, loop ileostomy takedown lengthens the hospital stay, increases the time to oral feeding, and has a 2-fold higher wound infection rate compared with that of end-ileostomy takedown. In addition, loop ileostomy requires significantly more outpatient stoma care and is associated with more frequent anal complications (Fonkalsrud, 2000). Finally, it is important to mention the use of minimally invasive surgical technique for total colectomy. Over the past 10 years, several centers have reported success with using laparoscopy to perform the total colectomy combined with transanal mucosectomy to completely remove the diseased colon and rectal mucosa. An ileo-anal anastomosis (with or without J Pouch) can be successfully performed as described above. The main disadvantage of the laparoscopic approach is the increase in total operating time compared to open surgery. However, preliminary data suggests decreased length of hospital stay, shorter time to return to normal activities and school, and improved cosmetic results. This technically demanding laparoscopic operation has also been performed successfully using robotic assisted technology. Postoperative details: After ileal pouch-anal procedures, patients are treated as with any bowel procedure. Their diet is changed as bowel function returns. They are weaned from steroid use. At 6-12 weeks, diverting ileostomies are evaluated for closure. This evaluation usually involves contrast-enhanced imaging of the pouch to assess healing. Once the ostomy is taken down, stool frequency is evaluated, and the need for bulk-forming agents or motility agents determined. Follow-up care: While the incidence of colon adenocarcinoma is greatly reduced with total proctocolectomy and ileal pouch-anal anastomosis, it is not zero. In patients with chronic pouch inflammation, villous hypertrophy and dysplasia may occur. While dysplasia has never been found within the pouch of a pediatric patient, chronic inflammatory changes have, leading to the supposition that dysplasia may develop. Yearly screening endoscopy has been recommended for the 5 years after the procedure. In children who have chronic inflammatory changes in the pouch reservoir, yearly screening endoscopy should be performed. If no inflammation is present, screening endoscopy may be performed every 2 years (Sarigol, 1999).
Several complications have been reported after ileal pouch-anal procedures. The anastomotic leak rate is 7-9% (Durno, 1999; Simchuk, 2000). If this leak occurs, fecal diversion, percutaneous drain placement, or repeat surgery with removal or revision of the reservoir is required. Pelvic abscess, which frequently accompanies an anastomotic leak, occurs in about 5% of cases (reports vary from 0-25%). Among patients with a pelvic abscess, 26% require excision of the pouch. Only 5.9% of patients without an abscess have pouch failure that requires removal. If the abscess is managed with diversion and drainage, the pouch may be spared. However, these patients have higher rates of long-term incontinence and pain compared with those without abscesses (Farouk, 1998). In patients who require pouch excision due to abscess, a gracilis muscle interposition flap has been used to maintain the anal canal and allow future attempts at pouch procedures (Shamberger, 2000). Pouch-vesicle, pouch-vaginal, pouch-anal, and enterocutaneous fistulas occur with a frequency of about 1% each. Pouchitis is defined as a clinical syndrome in which the patient has increased stool frequency, malaise, fever, or incontinence that responds to antibiotic therapy. The most frequently used antibiotics are ciprofloxacin or metronidazole (Simchuk, 2000). The incidence is reported to be 40-60%. Risk increases with time, as 18% have pouchitis at 1 year, and 48%, at 10 years (Durno, 1998; Simchuk, 2000; Meagher, 1998). Pouch dilatation and pouch-anal anastomotic stricture may lead to fecal stasis and predispose the patient to pouchitis. Patients without a pouch rarely develop pouchitis and have comparable stool frequency with time.
Outcomes of pouch procedures are classified as good to excellent in as many as 90% of patients. Stool frequency is less than 5 per day in as many as 74%. Difficulty with evacuation occurs in 20%. About 77% of patients require no dietary restrictions, while the remaining patients have a lower stool frequency with a low-fat diet (Karlboom, 2000). Complete incontinence is reported in only 2%. Bulk-forming agents are required in as many as 30%. Sexual dysfunction, manifest by retrograde ejaculation or impotence, occurs in 3% of males. Sexual dysfunction occurs in 6% of females and is manifest by dyspareunia or psychological aversion to intercourse for fear of stool leakage (Meagher, 1998). For excellent patient education resources, visit eMedicine's Crohn Disease Center and Esophagus, Stomach, and Intestine Center. Also, see eMedicine's patient education articles, Inflammatory Bowel Disease, Crohn Disease, and Crohn Disease FAQs.
Every patient who undergoes an ileal pouch-anal anastomotic procedure, as currently performed, must be able to accept the possibilities of stool seepage or incontinence and frequent bowel movements, with a minimum of 4-6 per day. Although the procedure results in removal of the diseased organ and although it is more technically advanced than end ileostomy, it is not a perfect solution. Surgical techniques can be improved to ensure better postoperative functional outcomes. Additional research may show that genetic predispositions, errors in oxidative metabolism, infectious causes, or autoimmune abnormalities are the primary causes of UC. If so, directed therapies could be pursued. Present research is focused on the potential benefits of the use of additional immunosuppressive agents such as Methotrexate or cyclosporine alone or in combination with mannose-6-phosphate (6-MP), prednisone, or azathioprine. Finally, the use of directed antibody therapy is in its infancy. Indications and contraindications to these therapies continue to evolve.
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