Ulcerative Colitis Inflammation: How It Changes the Colon
Ulcerative colitis (UC) is most often defined by its well-established symptoms: cramping, diarrhea, stomach noises, etc. And most patients with UC know these outward effects very well—some would say a little too well!
What patients know less about are the physical changes occurring within the colon (i.e. the large intestine); many patients don’t realize that, over time, there is ongoing damage and scarring that occurs as a direct result of the inflammation characteristic of the disease.
But the extent of damage is proportional to the inflammation—more specifically the amount of tissue affected and the duration of disease activity. For instance, inflammation that affects a large area and lasts a long time will cause more damage than more limited inflammation that’s treated early.
Effects of scarring
The good news is, the colon is wide enough that – even after a fair amount of scarring – there are fewer obstructive complications like strictures, fistulas, and abscesses than those reported in Crohn’s disease (in the small intestine). The bad news is, colon scarring still causes a number of physical changes: the colon itself becomes shorter, the tissue structure – typically containing folds and valves – is compromised, and patients may develop something known as “lead pipe” colon.
Lead pipe colon is how the colon looks after it has lost its normal surface texture—it appears like a rigid and featureless tube.
One effect of lead pipe colon is that there is less surface area available to absorb water, which can lead to diarrhea and subsequently, dehydration. This loss of elasticity and function in the colon tissue may also impact the colon’s motility – or ability to contract – but the severity of this phenomenon has not been well established.
The rarest but most severe form of ulcerative colitis, this condition is characterized by severe inflammation, which affects the entire thickness of the colon. It can result in dangerous complications, such as a ruptured colon and toxic megacolon.
Toxic megacolon occurs when the colon dilates, losing its ability to contract properly thus preventing the movement and passage of intestinal gas. The gas builds up so that the abdomen becomes severely distended (i.e., extremely bloated) and other symptoms like fever, fast heart rate, pain or even shock may set in.
Toxic megacolon can be life-threatening and therefore requires immediate medical attention. Talk to your healthcare team if you’re interested in learning more.
During an episode of toxic megacolon, the colon may weaken to such an extent that a hole develops in the intestinal wall. This perforation can be life threatening because the contents of the intestine – which include a large number of bacteria – can spill into the abdomen and cause a serious infection, called peritonitis.
Peritonitis is an inflammation of the peritoneum—the tissue that lines the inner wall of the abdomen and covers abdominal organs. Left untreated, peritonitis can rapidly spread into the blood and to other organs, resulting in multiple organ failure and even death.
If you develop any of the symptoms of peritonitis (the most common being severe abdominal pain) it’s critical to seek medical attention immediately.
While it may be a scary and unpleasant thing to discuss, UC-related inflammation causes damage to the colon, which is a known risk factor for colon cancer. In fact, about 5–8% of people with UC will develop colon cancer within 20 years of their diagnosis. This is more likely in people with uncontrolled UC inflammation for years, and much less likely in people who have had consistent control of their UC.
In general, people who have normal appearing colons (at colonoscopy) after control of inflammation are at lower risk, but patients with evidence of lead-pipe colon, scarring, or pseudopolyps are at higher risk of colon cancer. Patients with colon strictures from IBD have a risk of colon cancer of about 3% per stricture. It is critically important for all people with UC to get regular colon cancer screening with colonoscopy, starting 8 years after diagnosis.
Talk to your healthcare team of about proactively managing your UC, to keep your colon in the best possible shape and help minimize disease-related risks.