This transcript has been edited for clarity.
There are several indications for performing colonoscopy in patients with ulcerative colitis: confirming the diagnosis and separating ulcerative colitis from other inflammatory disorders; assessing the extent and severity of disease to determine the treatment intensity; therapeutic monitoring and treating to endoscopic targets to demonstrate endoscopic healing; and finally, for cancer surveillance.
Confirming the Diagnosis
The diagnosis of ulcerative colitis is based on a combination of clinical, endoscopic, and histopathologic findings (Figure 1).
There are actually very few clinical manifestations of ulcerative colitis that could be noted on a physical examination. The exceptions are those patients with very severe disease, abdominal tenderness, or who appear anemic.
Laboratory studies are also nonspecific but should be performed to determine the blood count and to rule out infections.
Endoscopy, or colonoscopy, is the hallmark for the diagnosis of ulcerative colitis and separating it from other inflammatory disorders of the colon. This is due to the fact that performing colonoscopy provides the ability to take biopsies and the histologic confirmation of ulcerative colitis.
Figure 1. Clinical, endoscopic, and histopathologic findings.
Ruling Out Mimics of Ulcerative Colitis
There are a number of mimics of ulcerative colitis.
Drug-induced colitis can mimic ulcerative colitis and result from a bowel preparation itself. Nonsteroidal anti-inflammatory drugs are one of the most common affecting medications that can contribute to ulceration throughout the small and large intestines. Checkpoint inhibitors have been demonstrated to cause a colitis that is very similar to ulcerative colitis. Drugs such as interleukin-17 inhibitors may also aggravate or actually induce ulcerative colitis.
In women, endometriosis may involve the colon and cause symptoms that mimic ulcerative colitis, which can be confirmed at colonoscopy.
Commonly, diverticulitis or segmental colitis associated with diverticular disease is a mimic for ulcerative colitis, as is a solitary rectal ulcer that can produce urgency and rectal bleeding.
Another important aspect of colonoscopy in the management of ulcerative colitis is to determine the extent and severity of disease (Figure 2).
Defining the extent of disease will allow us to treat patients either orally or rectally, depending on the proximal range of inflammation. The severity of inflammation will also dictate the intensity of treatment that patients will need. Extensive colitis and deep ulcerations are factors associated with moderate to severe disease and the need for advancing medical therapy.
Figure 2. Risk stratification.
We determine the severity of inflammation in ulcerative colitis according to the Mayo Score (Figure 3).
A Mayo 0 is a normal bowel; a Mayo 1 includes distortion of the mucosal vasculature; a Mayo 2 is exemplified by superficial erosions; and a Mayo 3 has visible ulcerations that portend a poor prognosis, along with a greater need for colectomy and more intense medical therapy.
Figure 3. Spectrum of colonoscopy findings in ulcerative colitis.
Image courtesy of Stephen B. Hanauer, MD.
Goals of Treatment
Colonoscopy is used as a component of our treat-to-target concept in ulcerative colitis (Figure 4). We treat to induce remission that is manifest by a normal appearance at colonoscopy.
We monitor patients on a schedule that is dependent upon how severe they are initially and how rapidly they respond. We continue monitoring as we would for blood pressure in a patient with hypertension.
When we do treat to the endpoint of endoscopic improvement or endoscopic healing, we improve the course of the disease and minimize risks for relapse, hospitalizations, and surgery.
Figure 4. Overview of the treat-to-target concept.
Image used with permission: Clinical Gastroenterology and Hepatology, June 2015
Cancer surveillance in ulcerative colitis is an important indication for colonoscopy. The cancer sequence in ulcerative colitis evolves from inflammation to microscopic dysplasia, visible dysplasia, and eventually cancer.
In addition to surveillance using colonoscopy, we have used chromoendoscopy over the past several years. In chromoendoscopy, a dye is applied to the mucosa that outlines dysplastic areas (Figures 5, 6). This is very important in the ongoing care of those with ulcerative colitis, and also in the prevention of colon cancer in these patients.
Figures 5 and 6. Sessile polyps with methylene blue chromoendoscopy.
Images courtesy of Rajesh Keswani, MD.
To summarize, in the setting of ulcerative colitis, confirming the diagnosis and ruling out mimics, assessing the extent and severity of disease, monitoring for endoscopic improvement, and surveilling for cancer over the ensuing years are all indications for colonoscopy.
Thank you for your attention.
Medscape Gastroenterology © 2021
Cite this: The 5 Goals of Colonoscopy in Ulcerative Colitis - Medscape - May 21, 2021.