Sabiston IBD

Question 1

Crohn disease

Answer 1

smoking tends to exacerbate symptoms.

Antibiotic use in early life has also been thought to predispose to IBD, as has NSAID use.

Question 2

in CD , Something Should Always be Performed

Answer 2

Digital rectal examination should always be performed.

Question 3

One of the most serious joint manifestations is

Answer 3

ankylosing spondylitis which runs a course independent of the bowel disease.

These patients are HLA-B27 positive

Question 4

Erythema nodosum

Answer 4

is characterized by red painful swollen nodules that can occur and usually will respond to systemic steroid administration

Question 5

pyoderma gangrenosum

Answer 5

characterized by typically extremely painful ulcerating lesions that frequently occur at sites of repeated trauma such as in the vicinity of surgical incisions or more frequently around intestinal stomas

There is a phenomenon called “pathergy,” which refers to a worsening of the pyoderma with any type of surgical manipulation or debridement.

These lesions are therefore best treated by nonoperative means and can include intralesional steroid injections (i.e., triamcinalone), topical (tacrolimus 0.1%), or systemic biologic therapy (anti-tumor necrosis factor [TNF] antibodies

Question 6

inflammation begins at

Answer 6

With UC, inflammation begins at the level of the dentate line and extends proximally

whereas in Crohn disease, in many cases, the inflammation is more patchy and there can be discontinuous inflammation (i.e., skip areas)

Question 7

One of the most common scoring systems for endoscopic assessment of UC is the Mayo Clinic Scoring System

Answer 7

based upon the severity of the mucosal ulceration or the absence

Grade 1 refers to a normal endoscopic appearance

grade 2 refers to slightly more erythematous

grade 3 refers to even more erythematous area with touch bleeding

grade 4 refers to significant bleeding and friability.

Question 8

Crohn disease is more characterized by

Answer 8

deeper punched-out appearing ulcerations

often longer serpiginous ulcerations covered with fibrin. These can oftentimes extend longitudinally along the lumen of the bowel, in which case they are sometimes referred to as “bear claw” ulcerations

In many cases, Crohn disease ulcers are worse on the mesenteric side of the bowel.

Regarding the distribution of Crohn disease, the most common site of involvement in nearly half of patients is ileocolic, followed by colonic involvemen

Question 9

As a rule, inflammation in UC is restricted to

Answer 9

the surface epithelium

Question 10

In biopsy specimens, the diagnosis of Crohn disease is made in the presence of

Answer 10

non-necrotizing granulomas or the presence of transmural lymphoid aggregates in an area not deeply ulcerated

Question 11

IBD undetermined

Answer 11

refers to a subset of patients who have overlapping characteristics of both Crohn disease as well as UC on endoscopic biopsy. It is thought that up to 10% to 15% of patients

Question 12

indeterminate colitis

Answer 12

is made in patients in whom there is uncertainty of the diagnosis on evaluation of the colectomy specimen, since histologic features of both Crohn and UC are seen.

Overall, this diagnosis is more likely in patients with fulminant disease where the significant amount of inflammation interferes with precise disease diagnosis

Question 13

Thiopurines

Answer 13

“steroid-sparing” class of medication that are usually begun once patients are placed on steroids and perhaps have been unsuccessful in weaning off steroids after one or two attempts at pulse therapy

Question 14

The side effects of this therapy include

Answer 14

leukopenia and pancreatitis.

These side effects are largely seen in individuals who are homozygous for a variant of the enzyme thiopurine methyltransferase responsible for metabolizing these drugs poorly.

For this reason, many physicians now routinely perform thiopurine methyltransferase genotyping of patients to see whether they will be able to metabolize these drugs properly prior to initiating thiopurine treatment.

there is usually a 3- to 4-month lag time until these medications exert their therapeutic effect. For this reason, these medications cannot be used to treat a flare.

Long-term thiopurine use is also associated with a higher risk of developing non-Hodgkin lymphoma

Question 15

The side effects of methotrexate

Answer 15

include elevations in liver function tests, as well as pulmonary fibrosis. When methotrexate is given, patients require folic acid supplementation

Question 16

infliximab SE

Answer 16

reactivation of infections including tuberculosis, histoplasmosis, actinomycosis, and hepatitis.

For this reason, a careful patient history regarding these infections should be taken prior to consideration of treatment. In addition, before starting these drugs, the patient should have either a tuberculin skin test or undergo testing with QuantiFERON gold assay as well as obtain a hepatitis profile

associated with a higher risk of developing non-Hodgkin lymphoma compared to the general population. In addition, anti-TNF-α antibody has been associated with a low risk of hepatosplenic T-cell lymphomas

Question 17

marker to assess disease activity

Answer 17

either fecal calprotectin or lactoferrin that can be used as an inflammatory marker to assess disease activity.

Question 18

toxic megacolon having three or more of the following criteria present:

Answer 18

• tachycardia greater than 100
• leukocytosis greater than 12,000/dL3
• hypoalbuminemia less than 3 g/dL3,
• temperature greater than 38°C
• or a diameter of the transverse colon on a plain abdominal radiograph greater than 5 cm.

Three or more of these criteria meet the definition of toxic megacolon; note that a “megacolon” does not need to be present in order to meet this definition.

Question 19

Patients with longstanding UC (>8 years) have a high risk of developing dysplasia or cancer, as do those who have sclerosing cholangitis.

Answer 19

Once the disease has been present longer than 8 years, patients are advised to undergo regular (yearly) colonoscopic surveillance with or without chromoendoscopy.

Question 20

If multiple areas of low-grade dysplasia or areas of high-grade dysplasia are found

Answer 20

a colectomy is recommended to prevent the development of invasive adenocarcinoma.

The finding of colonic dysplasia in patients with longstanding UC is an indication for surgery

Question 21

There is currently somewhat of a controversy as to exactly who requires surgery and who requires continued observation with close surveillance

Answer 21

due to the development of high-definition colonoscopy, as well as the development of techniques of surveillance such as chromoendoscopy.

Chromoendoscopy involves the performance of colonoscopy with the spraying of dyes such as methylene blue or indigo carmine onto the colonic mucosa at the time of colonoscopy to highlight areas suspicious for dysplasia to permit targeted biopsies rather than just performing the random biopsies that were previously standard of care.

In addition to this, there has been recognition that there are different types of dysplasia.
The flat dysplasia that is difficult to detect and blends in with the surrounding mucosa is very different from the “polypoid” dysplasia that is apparent and can be treated in many cases like a polyp and removed

Question 22

UC Polypectomy

Answer 22

patients with UC have undergone “polypectomy” removal of dysplastic lesions and have been followed long-term without interval development of cancer

Question 23

however, still agreement that if there are multiple areas of flat dysplasia within the colon,

Answer 23

colectomy is indicated

Question 24

if an adenocarcinoma is identified

Answer 24

colectomy is indicated

Question 25

In certain patients, the presence of severe extraintestinal disease is also an

Answer 25

indication for surgery

Question 26

Indications for Surgery for Crohn Disease

Answer 26

- children with Crohn disease when they show failure to grow. - symptoms of obstruction secondary to fibrostenosing Crohn - perforating Crohn disease associated with abscess or fistula - associated cancer or dysplasia, as with patients with UC, are an indication for surgery

Question 27

ileal sigmoid fistula , enterocutaneous fistulas, Enteroenteric fistulae

Answer 27

- presence of a symptomatic ileal sigmoid fistula resulting in significant diarrhea bypassing the entire colon can be an indication for surgery. - The occurrence of enterocutaneous fistulas is an indication for surgery. - Enteroenteric fistulae are not an indication for surgery unless they are associated with significant symptoms of obstruction or discomfort.

Question 28

patients with fulminant colitis Surgical Option

Answer 28

Subtotal colectomy and ileostomy and Hartmann procedure

Question 29

“toxic megacolon”

Answer 29

- mucosa sloughs, the endotoxins within the bowel lumen are absorbed leading to a septic state characterized by > 1- leukocytosis, 2- tachycardia, 3- fever, and in severe cases, hemodynamic instability. > protein-losing enteropathy > 4- hypoalbuminemia. > If the colitis is severe > colonic ileus > 5- increased diameter of the transverse colon (>5 cm). The definition of toxic megacolon is made when any three of these five factors ( 3/5 ) are present. It is important to realize that a patient can have toxic megacolon without having a “megacolon” (i.e., they can just be “toxic” or septic from their colitis).

Question 30

One of the common complications of this procedure postoperatively is

Answer 30

a “blow out” of the Hartmann stump, resulting in a pelvic abscess. This complication many times can be avoided simply by leaving a very long Hartmann stump and incorporating this into the fascial closure of the midline abdominal laparotomy wound or the specimen extraction site if the stump dehisces and a wound infection develops, the wound is opened and there is a controlled mucous fistula rather than a deep pelvic infection. Once the patient has stabilized and weaned off immunosuppressant medications, usually after a period of 3 months, another procedure for restoration of intestinal continuity can be performed.

Question 31

Subtotal Colectomy and Ileorectal Anastomosis

Answer 31

- avoids complications of pelvic dissection such as disturbances of sexual function in men and reduced fertility - Patients with limited rectal involvement do best - need to undergo continued surveillance for dysplasia because they are at in an increased risk of cancer in the retained rectum over time

Question 32

Ileal Pouch–Anal Anastomosis

Answer 32

- S Pouches, W Pouches, and H Pouches - the simplest and easiest pouch and the one with the least complications is the J Pouch - This is created using 15-cm limbs of terminal ileum and two firings of a GIA stapler. - The apex of this J Pouch is then either stapled to the distal rectum, leaving a very short rectal cuff , or hand-sewn to the distal rectum after a 2-cm mucosectomy is performed. Currently, the stapled approach is preferred simply because it provides superior continence and it is much quicker to perform. However, in cases of dysplasia or cancer, hand-sewn approaches still may be warranted.

Question 33

Two fires of a linear stapler are required; either a

Answer 33

75- or 100-mm stapler can be used.

Question 34

IPAA, one stage vs two stage

Answer 34

- Many patients who are undergoing this operation are on immunosuppressives at the time of surgery or in poor nutritional state, this operation is commonly performed with temporary fecal diversion (temporary loop ileostomy). - This is in place for 2 to 3 months, during which these immunosuppressant medications are weaned and the patient regains their normal nutritional state. The temporary ileostomy can then be closed, typically without requiring a laparotomy. - In patients who are not on immune suppression and in good nutritional state (this usually refers to patients undergoing surgery for the findings of colonic dysplasia), the operation can safely be done in one stage without fecal diversion provided that there is no tension on the IPAA.

Question 35

Several technical maneuvers can be performed to lessen the tension on the IPAA.

Answer 35

- mobilization of the small bowel mesentery to the level of the pancreas - If distal traction is placed on the apex of the J pouch, it should easily reach just below the symphysis pubis - When this maneuver is performed, one can either feel or visualize which small bowel mesenteric vessel is under more tension, the superior mesentery vessels or the ileocolic vessels. The vessel with the greater amount of tension can be divided - “Peritoneal windowing” can also provide mesenteric length. This is a maneuver whereby small slits are created in the anterior and posterior peritoneum covering the mesenteric vessels.

Question 36

RF for Tension in IPAA

Answer 36

- obese > more difficult to obtain sufficient mesenteric length for the small bowel to reach tension-free to the pelvis. - Very tall individuals and those with a long torso, tension can be an issue as well.

Question 37

Fashioning of stapled ileal pouch–anal anastomosis

Answer 37

- circular stapler is used; typically a 29-mm stapler is selected. - A common error is to leave too long a segment of rectum, resulting in the persistent symptoms due to this retained segment of mucosa affected with inflammatory bowel disease (cuffitis).

Question 38

Common early complications of IPAA include

Answer 38

- nonhealing of the IPAA: > pelvic sepsis > ileal pouch–anal anastomotic fistulae > ileal pouch–vaginal fistulae > ileal pouch–anal anastomotic sinuses > ileal pouch–anal anastomotic strictures (often a reflection of anastomotic tension). Late complications include the diagnosis of Crohn disease, which is more common in patients who undergo emergent colectomy and in those patients who have a diagnosis of indeterminate colitis.

Question 39

With a “good” result, patients with IPAA will have up to

Answer 39

- six bowel movements within a 24-hour period, usually including one nocturnal bowel movement. - at about 6 months, there will be significant enlargement of the ileal pouch, allowing patients to reduce the amount of antidiarrheal medication they take to control their output.

Question 40

Continent Ileostomy

Answer 40

instead of continence being maintained by the anal sphincter, continence was maintained by an intussuscepted segment of ileum positioned between this reservoir and the end ileostomy A continent ileostomy is air and water tight; very prone to dessusception, rendering the stoma incontinent and requiring revisional surgery. This procedure works best in individuals with a thin body habitus as with heavier individuals the thicker mesentery also predisposes to dessusception

Question 41

in CD for Ileocolic Resection margins

Answer 41

In deciding margins of resection, one should select areas of bowel that feel normal and are not thickened and have a normal thickness of the bowel-mesenteric junction. The ability to palpate a discrete small bowel-mesenteric junction is usually a good indicator that the lumen is free of significant Crohn inflammation.

Question 42

in ileocolic anastomosis, the authors prefer a hand-sewn end-to-end anastomosis. Why ?

Answer 42

While there are many ways to construct the ileocolic anastomosis, the authors prefer a hand-sewn end-to-end anastomosis. Postoperatively, these anastomoses are very easy to evaluate endoscopically and to dilate in the event of recurrent disease, which is not true of side-to-side stapled anastomoses

Question 43

Proctocolectomy and Ileal-Pouch–Anal Anastomosis in CD

Answer 43

- providing that they do not have obvious perianal disease. - With the advent of newer and more potent immunosuppressive drugs, this procedure is considered an option in an educated patient who is aware of the increased risk of morbidity and the less favorable functional results (i.e., greater number of bowel movements) as compared to when this operation is performed for patients with UC. - In addition, there is, of course, a higher risk of fistulizing disease and the need to convert to an end ileostomy.

Question 44

Cancer Risk

Answer 44

in patients in whom there has been a cancer identified, total colectomy should be performed, as there have been studies showing colonic procarcinogenic mutations tracking along the colon and the risk of a subsequent cancer in other areas of the colon is high

Question 45

Postoperative Recurrence

Answer 45

- Crohn patients who smoke are at higher risk of early disease recurrence - as are patients younger than 30 years old and those who have already had two or more operations for fistulizing disease. early intensive medical treatment beginning very soon postoperatively may successfully reduce the risk of recurrence. Regular endoscopic monitoring of the lower GI tract for signs of recurrent disease is important to allow therapeutic intervention prior to the development of therapy-resistant fibrosis.