Understanding Ulcerative Colitis Types

by Tracy Davenport, Ph.D. Health Writer

If you or someone you love has inflammatory bowel disease (IBD), you may already be familiar with ulcerative colitis (UC), which affects men and women equally. This IBD targets the large intestine, causing many small sores or ulcers to form there that lead to inflammation, abdominal pain, diarrhea, weight loss, and/or rectal bleeding. Unlike its IBD cousin Crohn’s disease (which causes symptoms anywhere between the mouth and the anus), UC mainly affects the large intestine (a.k.a. the colon) and sometimes the rectum. Still, not all types of UC are the same.


Location Matters

Researchers suspect this autoimmune disorder may be triggered from a combination of genes, the immune system, and the environment. How UC presents itself is reminiscent of the famous real estate saying: location, location, location. There are three main types: proctitis, left-sided colitis (also known as distal colitis), and extensive colitis (also known as pancolitis). Each affects different parts of your colon or rectum. All three types begin at the end of the colon (in the rectum) and extend into the colon. Where the disease stops is what sets them apart.


About Ulcerative Proctitis

Ulcerative proctitis occurs when your inflammation begins at the rectum and spreads no more than about 7 to 8 inches into your colon. The symptoms of proctitis may include bloody bowel movements, rectal bleeding, a constant feeling that you have to go to the bathroom, rectal or abdominal pain, a mucus-laden discharge, or diarrhea, per the Cleveland Clinic. These symptoms may be with you all of the time, or they may wax and wane (which doctors refer to as “acute” symptoms).


With Proctitis, a Small Area Can Lead to Big Symptoms

Just because proctitis impacts a relatively small part of the colon, that doesn’t mean you shouldn’t take it seriously. “It can be just as debilitating as having UC throughout the entire colon," says Howard Kader, M.D., assistant professor at the University of Maryland School of Medicine and director of the Pediatric Inflammatory Bowel Disease Center in Baltimore. To determine if you have this or any type of UC, your doctor will do a physical exam, which may include stool samples, lab work, imaging work (like X-rays or CT scans), and/or a colonoscopy.

talking to doctor

Varying Symptoms of Proctitis Can Be Overlooked

Still, diagnosis can sometimes be tough with this condition, since symptoms are so variable, according to Chaim Ross, M.D., clinical director, NYU Langone Gastroenterology Associates in Long Island, New York. “Sometimes people have symptoms but they just don’t realize it's proctitis,” he says. “They can sometimes just think that’s their ‘normal.’ This can especially happen if the symptoms are [constant] and just stay the same, versus come and go.” Dr. Ross explains, “It is important to talk to your doctor if you suspect you have proctitis, because mild symptoms of proctitis can definitely go under the radar.”

pain on toilet

About Left-Sided/Distal Colitis

Continuous inflammation from the rectum into the colon to the splenic flexure (the sharp bend between your transverse colon and descending colon in your upper abdomen) is diagnosed as left-sided or distal colitis. Folks with this condition tend to present with diarrhea, blood in the stool, and abdominal pain. “Left-sided colitis is found in about 16% to 45% of patients,” explains Dr. Kader. Research shows that onset can be gradual or abrupt with on-and-off symptoms. “While you can't have more than one type of UC at a time, if not treated, distal ulcerative colitis can evolve into pancolitis, so the left-sided colitis can change to more extensive disease."


About Extensive Colitis/Pancolitis

Extensive colitis, also known as pancolitis, affects the entire colon. Pancolitis can cause bouts of bloody diarrhea that may be severe, plus abdominal cramps and pain, fatigue, and significant weight loss. “For each type of UC, the severity of the disease is really dependent on the pathology,” says Dr. Ross. “You can have a mild or severe case of any of the three types of UC. Usually, however, the more involved the colon is, the more severe the UC is. In other words, if you have severe proctitis and severe pancolitis, then the pancolitis is probably the most severe.”

medical scale

Symptoms of UC Can Sometimes Tip Off Type

Dr. Ross explains that while specific testing may need to be done to determine what type of UC you have, sometimes just hearing symptoms being described can offer clues. “Oftentimes, we can tell how severe the disease is based on symptoms that someone tells us. For example, if they have bloody stools, weight loss, dehydration, or failure to thrive, then the colon is probably more ill,” which might suggest extensive colitis/pancolitis. Even so, your doctor will almost certainly run a series of tests before confirming which type you have.

talking to doctor with COVID-19 mask

But UC Symptoms May Also Be Misleading

On the other hand, “some patients can have minimal symptoms, but when you directly visualize their colon you observe the inflammation to be more significant,” says Dr. Nandi, M.D., associate professor of clinical medicine at the University of Pennsylvania in Philadelphia. “This illustrates that patient symptoms may be less than the severity of their disease. Therefore, we encourage patients who are not diagnosed but have bowel changes [blood in stool, diarrhea, abdominal pain, weight loss unintentional for instance] to seek their physicians’ counsel and investigate.”

colon cancer

Managing UC, No Matter the Type, Is Key

Getting UC under control ASAP can improve quality of life—and also reduce your risk of cancer, according to Neilanjan Nandi, associate professor of clinical medicine at the University of Pennsylvania in Philadelphia. “Patients with proctitis [involving a small section of the rectum and colon] do not have an increased risk of colon cancer, but there's a slight increase, progressively thereafter, as more colon [becomes] involved. Pancolitis [which involves the entire colon] carries the highest risk of colon cancer over a lifetime. However, if inflammation is controlled, then there is less opportunity for pre-cancerous cells to develop and less lifetime risk of colon cancer.”

Group of friends eating salads and smiling.

Treat All Types of UC Early With the Goal of Remission

Dr. Kader, Dr. Ross, and Dr. Nandi are in agreement that early intervention and management of UC are import—leading to less disease activity and potentially a symptom-free life. According to Dr. Ross, “It’s important to catch them all early so you don’t have a progression of the disease. Catching UC early, no matter the type, can allow the treatment to be simpler.” Dr. Kader adds, “Mild disease severity, not the type of UC or where it’s located, is easier to treat than severe disease. With treatment intervention, the extent of the disease can be changed, and sometimes to complete remission.”

Tracy Davenport, Ph.D.
Meet Our Writer
Tracy Davenport, Ph.D.

Davenport is the founder of Tracyshealthyliving.com. Using the latest scientific research, she helps people live their healthiest lives via one-on-one coaching, corporate talks, and sharing the more than 1,000 health-related articles she's authored.