Sections

Presentation

History

Patients with suspected Crohn disease should be evaluated initially by their primary care team, and symptoms should be elicited in detail. Obtain a complete medical, surgical, social, and family history, and perform a detailed review of systems. Preliminary laboratory data (eg, inflammatory and anemia markers) may be helpful. If Crohn disease is suspected, the patient should be promptly referred to a gastroenterologist for consultation.

In children, document growth parameters; growth failure may precede gastrointestinal (GI) symptoms by years. The etiology of growth failure is multifactorial, with nutritional, hormonal, and disease-related factors all contributing. Any child or adolescent with persistent alterations in growth or delayed puberty should undergo appropriate diagnostic evaluation for Crohn disease.

General manifestations

Low-grade fever, prolonged diarrhea with abdominal pain, weight loss, and generalized fatigability are usually reported. Crampy or steady right lower quadrant or periumbilical pain may develop; the pain precedes and may be partially relieved by defecation. Diarrhea is usually not grossly bloody and is often intermittent. If the colon is involved, patients may report diffuse abdominal pain accompanied by mucus, blood, and pus in the stool.^{[1, 2, 11, 43, 44]}

It is important to note that colonic Crohn disease may be clinically indistinguishable from ulcerative colitis, with symptoms of bloody mucopurulent diarrhea, cramping abdominal pain, and urgency to defecate.

Crohn disease of the small intestine usually presents with evidence of malabsorption, including diarrhea, abdominal pain, weight loss, and anorexia. Initially, these symptoms may be quite subtle. Patients with gastroduodenal involvement more commonly have anorexia, nausea, and vomiting.^[45]Those with perianal disease may have debilitating perirectal pain, malodorous discharge from the fistula, and disfiguring scars from active disease or previous surgery.

Patients may also present with complaints suggestive of intestinal obstruction. Initially, the obstruction is secondary to inflammatory edema and spasm of the bowel and manifests as postprandial bloating, cramping pains (lower right quadrant), and borborygmi. Once the bowel lumen becomes chronically narrowed from fibrosis, patients may complain of constipation and obstipation. These symptoms generally do not improve with anti-inflammatory agents. Complete obstruction may sometimes be caused by impaction of undigested foods.

Enterovesical fistulae may manifest as recurrent urinary tract infections and pneumaturia, enterovaginal fistulae as feculent vaginal discharge, and enterocutaneous fistulae as feculent soiling of the skin. Development of fistulae into the mesentery or luminal microperforation may result in intra-abdominal or retroperitoneal abscess formation.

Location and extent

The patient’s clinical presentation is primarily determined by the location and extent of the disease. Although any area of the GI system may be affected in patients with Crohn disease, the most common site of the chronic inflammatory process is the ileocecal region, followed by the colon (about 20%), the small intestine alone (about 30%), the stomach (rarely), and the mouth.^[8]The esophagus is very rarely involved.^[1]

The terminal ileum is involved in 50-70% of children. More than half of these patients also have inflammation in various segments of the colon, usually the ascending colon. Gastric inflammation, duodenal inflammation, or both may be observed in as many as 30-40% of children with Crohn disease. The primary pancreatic manifestation is pancreatitis.

About 45% of cases of Crohn disease occur in the ileum and colon, 20% solely in the colon, 33% in the small bowel, and 5% in the gastroduodenal region and perianal region alone (fistula, abscess, anal ulcer or stricture, or fissure).^[45]Nearly 20-23% of patients with large bowel or small bowel disease have perianal complications, which may precede the development of intestinal symptoms and manifest as simple skin tags, anal fissures, perianal fistulae, or abscesses.^[1]Symptoms may occur without involvement in any other area of the GI tract.

Physical Examination

The physical examination should focus on temperature, weight, nutritional status, the presence of abdominal tenderness or a mass, perianal and rectal examination findings, and extraintestinal manifestations (EIMs). Vital signs are usually normal in patients with Crohn disease, though tachycardia may be present in anemic or dehydrated patients. Chronic intermittent fever is a common presenting sign.

Abdominal findings may vary from normal to those of an acute abdomen. Diffuse abdominal tenderness or localized pain may be present.^[12]Fullness or a discrete mass may be appreciated, typically in the right lower quadrant of the abdomen (which is usual with ileal involvement), or a mass may be felt secondary to thickened or matted loops of inflamed bowel.

The perineum should be inspected in all patients who present with signs and symptoms of Crohn disease because abnormalities detectable in this region substantially increase the clinical suspicion of inflammatory bowel disease (IBD). Inspection of the perianal region can reveal skin tags, fistulae, ulcers, abscesses, and scarring. A rectal examination can help to determine sphincter tone and aid in detecting gross abnormalities of the rectal mucosa or the presence of hematochezia.

In addition to local complications, various EIMs may be associated with Crohn disease, usually involving the skin, joints, mouth, eyes, liver, or bile ducts.^[46]The most common EIMs are arthritis and arthralgia. The large joints (eg, hips, knees, ankles) are typically involved.^[6]

Examination of the skin and oral mucosa may show mucocutaneous or aphthous ulcers, erythema nodosum, and pyoderma gangrenosum. Skin examination may also reveal pallor in patients with anemia or jaundice in those with concomitant liver disease with cholestasis. Eye examination may reveal episcleritis. For the diagnosis of uveitis, a slit-lamp examination by an experienced physician is necessary.

Careful assessment of growth and development is an important part of evaluating pediatric patients. Growth abnormalities may be detected by evaluating the following parameters:

Height and weight
Height and weight percentiles for the patient’s age, as well as weight percentile for the patient’s height
Growth velocity
Body composition on anthropometry
Skeletal bone age

The most sensitive indicator of growth abnormalities in children is a decrease in growth velocity, which may be observed before the major percentile lines on standard growth curves are crossed. Decreased height velocity before the onset of intestinal symptoms can be observed in as many as 46% of patients with Tanner stage 1 or 2 development. Height at maturity is often compromised. Pubertal delay may precede the onset of intestinal symptoms, and accurate Tanner staging should be a part of routine physical examination.

Intestinal Manifestations

The major intestinal complications of Crohn disease are due to the transmural nature of the disease, which leads to the formation of abscesses, fistulae, sinus tracts (incomplete fistulae ending in a cul-de-sac), strictures, and adhesions. These features may also contribute to bowel obstruction.

Microperforation typically occurs into other segments of bowel, leading to fistulae, or into areas such as the retroperitoneum, resulting in abscess formation. Perianal and perirectal fistulae occur in approximately 20-23% of individuals. Other complications of fistulizing disease include enterovesical, enterocutaneous, and rectovaginal fistulae, as well as extension into muscle in severe progressive cases.

Frank perforation is more uncommon, but it is one of the most serious complications of Crohn disease if it occurs. The presenting features of frank perforation are those of classic peritonitis, although these features can sometimes be masked by high-dose corticosteroid or immunosuppressant therapy.

Colonic malignancy is a clinically significant complication of Crohn disease with colonic involvement. Chronic inflammation is the conjectured etiology for the development of dysplasia followed by cancer. Most cases of colorectal cancer develop from early histologic lesions referred to as low-grade dysplasia (LGD) or dysplasia-associated lesion or mass (DALM). Sporadic adenomas can also progress to colon cancer. These are premalignant or precancerous lesions that progress to cancer via a pathway of inflammation and genetic mutations.

A meta-analysis revealed that the cumulative risk of colon cancer in Crohn disease approaches 3% at 10 years and 8% at 30 years.^[47]It is widely known that individuals diagnosed at a younger age have a long disease duration (> 8 years), and that those with concomitant primary sclerosing cholangitis are at an increased risk for colorectal cancer.

The association of IBD with increased risk of colon cancer has led to North American consensus statements that recommend regular surveillance with colonoscopy every 1-3 years for those with either ulcerative colitis or colonic Crohn disease who have a disease duration longer than 8 years.

However, subsequent studies yielded different findings regarding the risk for colorectal cancer in people with Crohn disease. A population-based study did not show any temporal trends in colorectal cancer for Crohn disease, nor did it find an increased risk of such cancer in patients with this condition as compared with the general population.^[48]In contrast, a health maintenance organization (HMO) study from Northern California found a 60% increased relative risk of colorectal cancer, which did not change over a 12-year period.^[49]

Overall, with the advent of new technology (eg, chromoendoscopy) and the accumulation of evidence for the use of chemoprophylactic agents (eg, 5-aminosalicylic acid [5-ASA] and low-dose ursodiol), it appears that there may be a reduction in the risk for colorectal cancer in Crohn disease. At present, surveillance colonoscopy every 1-3 years remains the standard of care.

There is also a significant association between small bowel cancer and Crohn disease. However, the absolute risk is low. Future research may be helpful in clarifying incidence rates, duration and extent of disease, medication use, and other disease-modifying factors (eg, smoking) that may alter the risk stratification for small bowel cancer and Crohn disease.

Extraintestinal Manifestations (EIM)

EIMs may carry prognostic importance in Crohn disease.

Musculoskeletal disease

Musculoskeletal pain is considered the most common EIM of adult IBD, occurring in 9-53% of affected patients.^{[50, 51, 52]}The differential diagnosis of this condition is vast and includes IBD-associated arthritides such as arthralgia (5-20%), ankylosing spondylitis (1-26%), psoriatic arthritis, reactive arthritis, and sacroiliitis, as well as fibromyalgia and osteoporosis and osteoporosis-related fractures.

The most common EIM in children and adolescents is arthritis (7-25% of pediatric patients), which may occur years before any GI symptoms develop and may persist after surgical or medical remission of the disease. The arthritis is usually seronegative, transient, and nondeforming; has an asymmetric distribution; and involves the large joints of the lower extremities.

In adults, the arthritis occurs when the disease is active and can affect large and small joints. Type 1 peripheral arthritis is pauciarticular (< 5 joints), and is strongly associated with IBD activity and other EIMs. The joint most commonly involved is the knee. Type 2 peripheral arthritis is polyarticular and independent of disease activity. The metacarpophalangeal (MCP) joint is the most commonly involved site; less frequently, the knees, ankles, shoulders, proximal interphalangeal (PIP) joint, and metatarsophalangeal (MTP) joint may be involved.

Dermatologic disease

Dermatologic EIMs occur in 2-34% of Crohn patients, with erythema nodosum the most common manifestation. Erythema nodosum is more common in Crohn disease than in ulcerative colitis and usually follows the course of the disease. This condition affects 3% of pediatric patients with Crohn disease and is less frequent than in adults. Approximately 75% of patients with erythema nodosum ultimately develop arthritis.

The lesions of erythema nodosum are raised, red, tender nodules that appear primarily on the anterior surfaces of the lower leg. These ulcers can be either solitary or multiple and either unilateral or bilateral, and they can range in size from several centimeters to distribution along an entire limb.

Although pyoderma gangrenosum is uncommon in Crohn disease, it may occur, even when the disease is in remission: 50% of patients will develop the rash despite quiescent Crohn disease activity. Therefore, medical therapy for the underlying bowel disease is not always successful. Consultation with a dermatologist may be necessary.

Other dermatologic manifestations include the following:

Sweet syndrome
Orofacial granulomatosis
Angular and aphthous stomatitis
Acrodermatitis enteropathica
Alopecia
Metastatic Crohn disease
Crohn disease of the vulva and penis
Psoriasis

Oral lesions

Aphthous ulceration in the mouth is the most common oral manifestation of Crohn disease, and it is commonly associated with skin and joint lesions. Oral lesions appear to parallel intestinal disease in most cases, but they may also develop before any GI symptoms occur.

Ophthalmologic disease

Ophthalmologic manifestations of Crohn disease (primarily episcleritis and anterior uveitis) most frequently occur when the disease is active. The rate of such manifestations is 0.5-5% in the adult population but is lower in children and adolescents.

The most common ocular manifestation is episcleritis, or inflammation of the vascular-rich episclera. Episcleritis should be suspected in patients who present with acute redness in one or both eyes, irritation, and burning. Uveitis is usually symptomatic, causing pain or decreased visual acuity. Treatment for these ocular EIMs is geared toward controlling the underlying bowel disease.

Other manifestations may include increased intraocular pressure and cataracts in children who receive corticosteroid therapy. Conjunctivitis also occurs. All patients with Crohn disease require ophthalmologic examination at regular intervals.

Urologic disease

Urologic EIMs include nephrolithiasis, hydronephrosis, and enterovesical fistulae. The incidence of gallstones and kidney stones is increased in Crohn disease because of malabsorption of fat and bile salts. Nephrolithiasis occurs in fewer than 5% of children with Crohn disease, usually as a result of the fat malabsorption that occurs with small bowel Crohn disease. Dietary calcium binds to malabsorbed fatty acids in the colonic lumen; therefore, free oxalate is absorbed. The absorption of free oxalate results in hyperoxaluria and oxalate stones.

Gallstones are formed as a consequence of an increased cholesterol concentration in the bile, caused by a reduced bile salt pool. In patients with an ileostomy, increased fluid and electrolyte losses may lead to concentrated acidic urine and the formation of uric acid stones. External compression of the ureter by an inflammatory mass or abscess may lead to hydronephrosis. Enterovesical fistulae may present with recurrent urinary tract infections or pneumaturia.

Hepatobiliary disease

Hepatobiliary disease is among the most common EIMs of Crohn disease and its therapies. Abnormal serum aminotransferase levels are common during the course of Crohn disease in children. Most aminotransferase elevations are transient and appear to relate to medications or disease activity. Aminotransferase elevations that persist for longer than 6 months should be investigated because the likelihood of serious liver disease is increased.

Both intrahepatic and extrahepatic manifestations of liver disease occur in children with Crohn disease. Intrahepatic manifestations include chronic active hepatitis, granulomatous hepatitis, amyloidosis, fatty liver, and pericholangitis. Extrahepatic manifestations include cholelithiasis and obstruction.

Cholelithiasis is more frequent in patients with IBD than in the general population, probably because of bile salt pool alteration from malabsorption. Chronic active hepatitis and sclerosing cholangitis develop in fewer than 1% of children with Crohn disease. Sometimes, a hepatic abscess manifests as fever of unexplained origin.

Primary sclerosing cholangitis is a progressive chronic liver condition of unknown etiology that increases the risk for cholangiocarcinoma and colorectal cancer in patients with IBD. Patients can be asymptomatic with mild elevations of transaminase and alkaline phosphatase, or they may present with advanced findings of cholangitis and jaundice. Magnetic resonance cholangiopancreatography (MRCP) or endoscopic retrograde cholangiopancreatography (ERCP) typically reveals strictures of medium and large intrahepatic and extrahepatic bile ducts.

Primary sclerosing cholangitis has an established strong association with IBD, particularly ulcerative colitis. About 5-10% of patients with primary sclerosing cholangitis have Crohn disease, but only 2% of Crohn disease patients develop primary sclerosing cholangitis. There is a 2:1 male prevalence for the disorder.

The clinical course of primary sclerosing cholangitis does not parallel bowel disease, and this condition can develop in the years before or after the development of GI symptoms. Patients with this disease may require transplantation if cirrhosis develops or if severe recurrent cholangitis occurs.

Other pancreatic or hepatobiliary manifestations of Crohn disease include the following:

Cirrhosis related to long-standing primary sclerosing cholangitis
Portal vein thrombosis
Cholangiocarcinoma
Pancreatitis (idiopathic or drug-induced)

Thromboembolic disease

Thromboembolic disease is considered to be the result of a hypercoagulable state that parallels disease activity and is manifested by thrombocytosis, elevated plasma fibrinogen, factor V, factor VIII, and decreased plasma antithrombin III. This state may lead to deep vein thrombosis, pulmonary embolism, and neurovascular disease.

Compared with control subjects, patients with IBD have a 3-fold higher risk of thromboembolism. These patients have frequent exposure to classic thrombosis risk factors, including immobility, surgery, steroid therapy, and the presence of central venous catheters. Other factors that may play a role include smoking, antiphospholipid antibody syndrome, and hyperhomocystinemia.

Additional extraintestinal diseases

Bone metabolic disorders include osteopenia and osteoporosis. Hematologic manifestations include iron deficiency anemia, vitamin B-12 deficiency anemia, folate deficiency anemia, anemia of chronic disease, autoimmune hemolytic anemia, thrombocytosis, anemia due to GI bleeding, and thrombosis.

Genitourinary manifestations include nephrolithiasis, obstructive uropathy, glomerulonephritis, and amyloidosis. Pulmonary manifestations include granulomatous lung disease, fibrosing alveolitis, and pulmonary vasculitis. Cardiovascular manifestations include pericarditis, myocarditis, and vasculitis.

Malabsorption can occur as a result of loss of functional mucosal absorptive surface. This phenomenon can lead to protein-calorie malnutrition, dehydration, and multiple nutrient deficiencies. Involvement of the terminal ileum may result in malabsorption of bile acids, which leads to steatorrhea, fat-soluble vitamin deficiency, and gallstone formation.

Fat malabsorption, by trapping calcium, may result in increased oxalate excretion (normally complexed by calcium), causing kidney stone formation. Steatorrhea and fat-soluble vitamin deficiency may also lead to clotting abnormalities, calcium deficiency, and osteomalacia, which may progress to osteoporosis. Vitamin B-12 deficiency may also occur with ileal resection or long-standing ileal disease.^[1]

Disease Classification and Activity Scoring Systems

A system to homogenize the classification of IBD on the basis of disease location and behavior was first established in 1998 in Vienna, Austria.^[53]Further developments in the field were reviewed, and the Montreal revision of the Vienna classification was proposed (see below), with special attention to predominant parameters of age at diagnosis, location, and behavior of disease.^[54]

Montreal classification system

The Montreal revision of the Vienna system is based on the following 3 variables:

Age at diagnosis
Disease distribution/location
Disease behavior

Age at diagnosis (A) has 3 categories, as follows^[54]:

A1 – ≤ 16 years
A2 – 17-40 years
A3 – > 40 years

Disease distribution/location (L) has the following 4 categories, 1 of which is a modifier for upper GI involvement^[54]:

L1 – Ileal
L2 – Colonic
L3 – Ileocolonic
L4 – Isolated upper GI disease; L4 is a modifier that can be added to L1-L3 when there is concomitant upper GI involvement

Disease behavior (B) has 1 interim category (B1) and 2 specified categories, with an additional modifier for perianal diseases (p), as follows^[54]:

B1 – Nonstricturing, nonpenetrating; B1p: nonstricturing, nonpenetrating with perianal involvement
B2 – Stricturing; B2p: stricturing with perianal involvement
B3 – Penetrating; B3p: penetrating with perianal involvement

Crohn disease activity indices

Multiple scoring systems incorporating the patient’s history, physical examination findings, and laboratory data have been developed to assess disease activity in adults with Crohn disease. These scoring systems are used principally for assessing the efficacy of treatment and evaluating new therapies for research purposes.

One such index is the Crohn Disease Activity Index (CDAI), which was developed for use in adults. The Pediatric Crohn Disease Activity Index (PCDAI) was developed and validated in 1990; the results are correlated with the physician’s global assessment and with the Harvey-Bradshaw index (HBI), and they have significant interobserver reliability. The important difference between the PCDAI and the CDAI is the inclusion of growth parameters in the PCDAI score.

A modified PCDAI (Mod PCDAI), consisting of the laboratory measures of the PCDAI plus the C-reactive protein (CRP) level, has been shown to correlate with the PCDAI, the physician’s assessment, and fecal calprotectin.^[55]This modified index can be used as an alternative to the PCDAI, with the advantage of having additional objective laboratory values embedded in it.^[55]Other authors have described a short PCDAI.^[56]

Other activity indices and their parameters used for clinical and research purposes include the following:

HBI – General well-being, abdominal pain, number of liquid stools per day, presence of abdominal masses, and complications or EIMs
Seo index – General well-being, amount of blood in stool, number of bowel movements during the day and the night, urgency of defecation, and number of extracolonic manifestations
Perianal Crohn Disease Index (PDAI) – Perianal discharge, pain with restriction of daily activities, restriction of sexual activity, physician scoring of the type and number of perianal disease, and presence of induration
Fistula Drainage Assessment – Fistula healing, ranging from heavy drainage or abscess to complete closure

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Media Gallery

Crohn disease. The colonoscopy image reveals a large ulcer and inflammation of the descending colon in a 12-year-old boy with Crohn disease.
Crohn disease. This laparoscopic view depicts creeping fat along the mesentery of the terminal ileum.
Crohn disease. On this laparoscopic photograph, the mesentery of the terminal ileum is being coagulated with a sealing device (LigaSure). Note that the ligation of the mesentery proceeds near the border of the ileum rather than at the base of the mesentery.
Crohn disease. This postoperative photograph depicts incisions used for laparoscopic ileocolectomy in a 14-year-old male adolescent with obstruction of the terminal ileum. Note the 2-cm incision in the right lower abdomen, through which the specimen was extracted and extracorporeal anastomosis performed. A 12-mm umbilical incision is nicely hidden in the depths of the umbilicus. A 5-mm incision is visible in the left lower abdomen, and another is in the left suprapubic region just above the top of the pants.
Crohn disease. Colonic granuloma in a patient with Crohn disease is shown (hematoxylin-eosin staining). Image courtesy of Dr E. Ruchelli.
Crohn disease. Aphthous ulcers. A double-contrast barium enema examination in a patient with Crohn colitis demonstrates numerous aphthous ulcers.
Crohn disease. This double-contrast barium enema study demonstrates marked ulceration, inflammatory changes, and narrowing of the right colon in a patient with Crohn colitis.
Crohn disease. Cobblestoning in Crohn disease. This is a spot view of the terminal ileum from a small bowel follow-through study. It demonstrates linear longitudinal and transverse ulcerations that create a cobblestone appearance. Also, note the relatively greater involvement of the mesenteric side of the terminal ileum and the displacement of the involved loop away from the normal small bowel secondary to mesenteric inflammation and fibrofatty proliferation.
Crohn disease. Crohn disease of terminal ileum. The small bowel follow-through study demonstrates the string sign in the terminal ileum. Also, note the pseudodiverticula of the antimesenteric wall of the terminal ileum, secondary to greater distensibility of this less-involved wall segment.
Crohn disease. This spot view of the terminal ileum from a small bowel follow-through study in a patient with Crohn disease demonstrates the string sign, consistent with narrowing and stricturing. Also, note a sinus tract originating from the medial wall of the terminal ileum and the involvement of the medial wall of the cecum.
Crohn disease. Enterocolic fistula in a patient with Crohn disease. The double-contrast barium enema study demonstrates multiple fistulous tracts between the terminal ileum and the right colon adjacent to the ileocecal valve (so-called double-tracking of the ileocecal valve).
Crohn disease. Active small bowel inflammation in a patient with Crohn disease. This computed tomography scan demonstrates small bowel wall thickening, mesenteric inflammatory stranding, and mesenteric adenopathy.
Crohn disease. This computed tomography scan from a patient with terminal ileal Crohn disease shows an enteroenteral fistula (arrow) between loops of diseased small intestine.
Crohn disease. A teenaged patient with Crohn disease underwent contrast-enhanced, upper gastrointestinal computed tomography scanning with small-bowel follow-through. Several loops of small bowel are in the pelvis. Note the loop of distal bowel with thickened wall (solid arrow), which is contrasted with a less-involved loop of bowel in which the intestinal wall is not thickened at all (dotted arrow).
Crohn disease. This computed tomography scan depicts Crohn disease in the fundus of the stomach.
Crohn disease. This magnetic resonance image demonstrates an inflamed terminal ileum in 10-year-old girl with Crohn disease.
Crohn disease. The histologic image shows granuloma in the mucosa of a patient with Crohn disease.

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Table 1. Characteristics Differentiating Crohn Disease and Ulcerative Colitis

Characteristic
	Crohn Disease	Ulcerative Colitis
Distribution	Entire gastrointestinal tract	Colon only, though gastritis is recognized
Distribution	Skip lesions	Continuous involvement proximally from rectum
Pathology	Full thickness	Mucosa only
Pathology	Granulomas (15-30% in biopsy specimens; 40-60% in surgically resected bowel)	No granulomas
Radiology	Entire gastrointestinal tract	Colon only
	Skip lesions	Continuous involvement proximally from rectum
	Fistulae, abscesses, fibrotic strictures	Mucosal disease only
Cancer risk	Increased	Estimated to be 3% at 10 years, 8% at 30 years, and 18% at 30 years after diagnosis^[47]; risk is higher in patients with primary sclerosing cholangitis and long-standing colitis (> 8-10 y); may be lower in subsequent studies (see Intestinal Manifestations).
Presentation
	Crohn Disease	Ulcerative Colitis
Bleeding	Occasional	Very common
Obstruction	Common	Uncommon
Fistulae	Common	None
Weight loss	Common	Uncommon
Perianal disease	Common	Rare

Table 2. ASCRS Indications for Surgical Management of Crohn Disease

Operative Indication	Factors for Considering Surgery
Failed medical therapy	Presence of disease-related symptoms not responsive to medical management; condition demonstrates an inadequate response When first- and second-line therapies do not induce remission safely in severe disease Before escalating medical therapy in severe or steroid-dependent disease with limited extent (eg, disease with stricturing behavior, patients who have contraindications or risk factors for further medical therapy)
Perforation	Presence of symptoms or signs of free perforation Immediate resection of perforated segment (has a relatively high mortality) After small bowel resection or perforation, other procedures can be performed, as needed (eg, end stoma, diverted or nondiverted anastomosis)
	When large anteroparietal, interloop, intramesenteric, or retroperitoneal abscesses cannot be or are unsuccessfully managed with antibiotics and percutaneous drainage Perform surgical drainage in such cases, with or without resection
	Persistent enteric fistulae and symptoms or signs of localized or systemic sepsis despite appropriate medical management Persistent sepsis warrants excision of the diseased bowel, whether or not an abscess is present For target or “innocent bystander” organs, diseased bowel is typically resected, noninflamed bowel primarily closed, and other internal organs primarily closed or allowed to heal by secondary intention Note: Operative intervention may be avoided for asymptomatic internal fistulae
Obstruction	Presence of symptomatic strictures in regions not amenable or responsive to medical therapy
Obstruction	Presence of asymptomatic colonic strictures that cannot be adequately surveyed by biopsy or cytology brushing
Inflammation	Presence of acute colitis and symptoms or signs of impending or actual perforation (eg, transverse colon distention > 6 cm on abdominal x-ray or persistent gaseous colonic distention indicate toxic megacolon, pneumatosis coli, evolving local peritonitis, multiple organ failure) Presence of severe or fulminant colitis
Inflammation	Worsening acute colitis or failure to significantly improve despite 48-96 hours of appropriate medical therapy
Hemorrhage	Presence of massive hemorrhaging of any origin that (1) cannot be or fails to be managed with interventional or endoscopic techniques and (2) occurs in hemodynamically unstable patients Mesenteric angiography with embolization may be attempted when adequate endoscopic visualization is not possible or when the bleeding source cannot be identified; if this technique is not successful or the patient is hemodynamically unstable, laparotomy with or without intraoperative endoscopy and resection of the responsible bowel segment may be required
Neoplasia	Presence of chronic Crohn disease of the ileocolon or colon (endoscopic surveillance) Presence of adenomatous-appearing polyps (excision)
	Presence of carcinoma, DALM, high-grade dysplasia, multifocal colonic or rectal low-grade dysplasia (resection)
	Presence of chronic Crohn disease of the terminal ileum, ileocolon, or upper GI region
Growth retardation and EIMs	Presence of significant growth retardation in prepubertal patients despite appropriate medical therapy
Growth retardation and EIMs	Presence of symptomatic dermatologic, oral, ophthalmologic, or joint disorders refractory to medical therapy (resection of diseased intestine)
ASCRS = American Society of Colon and Rectal Surgeons; DALM = dysplasia-associated lesion or mass; EIM = extraintestinal manifestation; GI = gastrointestinal. Source: Strong SA, Koltun WA, Hyman NH, Buie WD, for the Standards Practice Task Force of The American Society of Colon and Rectal Surgeons. Practice parameters for the surgical management of Crohn’s disease. Dis Colon Rectum. 2007;50(11):1735-46.^[7]

Table 3. ASCRS Recommendations for Site-Specific Operative Management of Crohn Disease

Site	Surgical Intervention
Terminal ileum, ileocolon, upper GI tract	Resection of the affected bowel for jejunal, proximal ileal, terminal ileal, or ileocolic disease in the absence of existing or impending short bowel syndrome Ileocolostomy or proximal loop ileostomy in cases where there is concern about damage to nondiseased bowel, superior mesenteric vessels, retroperitoneal structures Drainage of any septic foci with later definitive resection (after several months’ delay)
	Strictureplasty for nonphlegmonous jejunal, ileal, or ileocolic strictures in the absence of existing or impending short bowel syndrome Strictureplasty when multiple jejunal or proximal/terminal ileum strictures are present
	Bypass or strictureplasty for symptomatic gastric or duodenal disease
	Endoscopic dilatation of symptomatic, accessible strictures of the intestinal tract Note: Surgical services should be available in case of perforation
Colon	Subtotal or total colectomy with end ileostomy for colonic disease requiring emergency or urgent surgery (via laparoscopic or open approach)
	Segmental or total colectomy with or without primary anastomosis for colonic disease requiring elective surgery
	Total proctocolectomy or proctectomy with stoma creation for rectal disease requiring surgery
ASCRS = American Society of Colon and Rectal Surgeons; GI = gastrointestinal. Source: Strong SA, Koltun WA, Hyman NH, Buie WD, for the Standards Practice Task Force of The American Society of Colon and Rectal Surgeons. Practice parameters for the surgical management of Crohn’s disease. Dis Colon Rectum. 2007;50(11):1735-46.^[7]

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Author

Leyla J Ghazi, MD Assistant Professor, Department of Medicine, Associate Program Director, Division of Gastroenterology and Hepatology, University of Maryland School of Medicine

Leyla J Ghazi, MD is a member of the following medical societies: American College of Gastroenterology, American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, Crohn's and Colitis Foundation of America

Disclosure: Nothing to disclose.

Specialty Editor Board

BS Anand, MD Professor, Department of Internal Medicine, Division of Gastroenterology, Baylor College of Medicine

BS Anand, MD is a member of the following medical societies: American Association for the Study of Liver Diseases, American College of Gastroenterology, American Gastroenterological Association, American Society for Gastrointestinal Endoscopy

Disclosure: Nothing to disclose.

Chief Editor

Praveen K Roy, MD, MSc Clinical Assistant Professor of Medicine, University of New Mexico School of Medicine

Praveen K Roy, MD, MSc is a member of the following medical societies: Alaska State Medical Association, American Gastroenterological Association

Disclosure: Nothing to disclose.

Acknowledgements

BS Anand, MD Professor, Department of Internal Medicine, Division of Gastroenterology, Baylor College of Medicine

BS Anand, MD is a member of the following medical societies: American Association for the Study of Liver Diseases, American College of Gastroenterology, American Gastroenterological Association, and American Society for Gastrointestinal Endoscopy