Risks and Complications of Untreated Ulcerative Colitis

The risks of untreated ulcerative colitis (UC) are many, affecting not only the gastrointestinal tract but also the eyes, joints, liver, kidneys, heart, and bones. As arguably the more severe form of inflammatory bowel disease (IBD), UC can lead to potentially severe complications if symptoms like bloody diarrhea and intestinal inflammation are allowed to go unchecked.

By getting UC treated and into a state of long-term remission, you can live a healthier, more productive life and avoid complications ranging from chronic anemia to colorectal cancer.

Chronic Anemia

One of the hallmark signs of ulcerative colitis is blood in your stool, also known as hematochezia. Even during the early stages of the disease, this can lead to anemia, a condition in which there are not enough red blood cells to carry oxygen to cells.

With untreated UC, anemia can become especially problematic as the bleeding may not only be chronic (persistent) but tends to get progressively worse. This can lead to a form of anemia known as anemia of chronic disease.

With chronic anemia, the lack of oxygen puts excessive strain on the heart and respiratory tract as they work harder to compensate for the loss. This can lead to a cascade of long-term complications such as:

• Hypertension (high blood pressure)
• Arrhythmia (irregular heartbeats)
• Heart failure (the inability of the heart to pump enough blood to service the body's needs)
• Chronic kidney disease (caused in part by increased blood pressure to the kidneys)
• Pulmonary hypertension (high blood pressure in the lungs)

In pregnant people, untreated anemia can cause premature birth and low birth weight.

Arthritis

Arthritis is the most common extraintestinal complication of IBD, affecting as many as 30% of people with UC or Crohn's disease (the other form of IBD).

Though arthritis is typically associated with aging, people with UC tend to get it at a far earlier age due to the persistent systemic (whole-body) inflammation induced by the disease.

In people with untreated IBD, the forms of arthritis most commonly seen include:

• Peripheral arthritis, usually affecting the large joints of the arms and legs, including the elbows, wrists, knees, and ankles
• Axial arthritis, which causes pain and stiffness in the lower spine and sacroiliac joints (located at the bottom of the back)
• Ankylosing spondylitis, a more severe form of axial arthritis that not only affects the spine but also causes inflammatory damage to the eyes, lungs, and heart valves

Fatty Liver Disease

Fatty liver disease (hepatic steatosis) is another common complication of untreated UC. This is when extra fat gets deposited in the liver, supplanting and damaging healthy liver cells and tissues. Research suggests that nearly two out of every three people with IBD meet the clinical criteria for fatty liver disease.

Fatty liver disease is more often seen in people with obesity or metabolic syndrome. With UC, it can occur in the absence of either of these conditions, caused by the collateral effects of chronic inflammation.

In the blood, chronic inflammation can change the structure of lipids (fats), making them more readily absorbed by the liver. As the liver starts to swell with accumulated fat, it can develop bands of fibrous scar tissues that irreversibly damage the organ, leading to cirrhosis and, in severe cases, liver failure.

Osteoporosis and Bone Loss

People with untreated UC can develop vitamin deficiencies due to malabsorption of nutrients in the intestines. Chief among these is vitamin D deficiency.

Vitamin D is the nutrient that helps calcium get into your bones, making them stronger. When there is not enough vitamin D in the body, the loss of calcium absorption can decrease bone mass (referred to as osteopenia), leading to osteoporosis (porous bones) and osteomalacia (softer bone).

Older females with UC are at greatest risk due to the co-occurring decline of estrogen during and after menopause. Untreated UC combined with the loss of estrogen (which supports bone growth) can lead to severe symptoms of osteoporosis at an earlier age. These include abnormal spinal curvature and an increased risk of pathologic fractures of the hip or spine.

Episcleritis and Other Eye Diseases

Episcleritis is the inflammation of the episclera, the thin layer of tissue between the sclera (the white of the eye) and conjunctiva (the clear membrane covering the eye).

Episcleritis is common with untreated UC. The combination of systemic inflammation and increased blood pressure can cause tiny blood vessels in the episclera to become swollen, leading to eye redness, pain, watering, and light sensitivity, The severity of episcleritis tends to mirror the severity of UC.

Although episcleritis tends to be relatively mild in most people, those with untreated UC may experience a more severe form called nodular episcleritis in which tiny bumps form on the surface of the eye.

Left untreated, UC can lead to the progression of eye disease, resulting in chronic uveitis (inflammation of the middle layer of the eye) and an increased risk of cataracts and glaucoma.

Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is a chronic progressive disease characterized by inflammation and scarring of the bile ducts that drain bile from the gallbladder. The scars make the ducts hard and narrow, causing the backflow of bile which can damage the liver.

Studies suggest that nine out of 10 people with PSC have UC or Crohn's disease. On the other hand, only one out of every 10 people with UC or Crohn's disease have PSC. People with poorly controlled IBD appear to be at greatest risk.

In people with UC, inflammation in the right side of the colon (cecum) is associated with a greater risk of PSC. The inflammation essentially "spills over" to the bile ducts, causing changes that lead to PSC.

In 10% to 20% of cases, PSC can lead to a rare form of cancer called cholangiocarcinoma affecting the bile ducts.

Bowel Perforation and Toxic Megacolon

Bowel perforation is a rare but potentially life-threatening complication of ulcerative colitis. It is more common in those with long-standing, severe UC whose intestinal walls have become swollen, wider, and thinner (referred to as fulminant colitis).

With bowel perforation, the contents of the intestine can spill into the abdomen and cause a serious infection known as peritonitis. Even with aggressive treatment, a bowel perforation with peritonitis poses a high risk of death, hovering around 30% to 50%.

Most cases of bowel perforation occur with a condition called toxic megacolon. This is the most severe form of fulminant colitis in which the colon spontaneously dilates (widens) and loses its ability to contract.

Toxic megacolon is a rare complication (most commonly seen in older adults with UC), but one that may require emergency surgery to avoid death.

Colorectal Cancer

People with ulcerative colitis have an increased risk of colorectal cancer (cancer of the colon or rectum). Research suggests that UC independently increases the risk of this cancer by sixfold compared to the general population. With that said, only around 5% of people with severe UC will end up developing colorectal cancer.

Colorectal cancer is most common in people with long-standing UC, with the risk progressively increasing after eight to 10 years. Those who experience pancolitis (meaning inflammation throughout the entire colon) are at greatest risk. Other risk factors include a family history of colorectal cancer or a co-occurring diagnosis of primary sclerosing cholangitis.

Research suggests that long-term remission can significantly reduce the risk of colorectal cancer in people with UC, highlighting the importance of early treatment.

Routine screening for colorectal cancer is recommended in people with long-standing UC. After eight to 10 years, a yearly colonoscopy is typically advised to check for polyps or early signs of cancer.

Summary

Ulcerative colitis (UC) can lead to potentially serious complications if left untreated, affecting not only the digestive tract but also the eyes, bones, kidneys, liver, heart, and gallbladder. These include complications like chronic anemia, arthritis, fatty liver disease, osteoporosis, episcleritis, primary sclerosing cholangitis, bowel perforation, and colorectal cancer.