Colon Polyps vs. Diverticulitis Symptoms and Signs Quick Overview
- Colon polyps usually are slow growing non-cancerous (benign) tumors derived from cells lining the large intestine. Less than 1% of colon polyps have abnormal cells, some may be cancerous (malignant).
- Colon polyps look like a mass or finger-like projection into the lumen of the large bowel. Some appear to be on stalks.
- Diverticulitis is inflammation of diverticula in the large bowel, which usually is caused by infection. Diverticula are the opposite of polyps because diverticula are small pouches that are open to the lumen (the channel within a tube such as a blood vessel or to the cavity within a hollow organ, for example, the large bowel).
- Colon polyps and diverticulitis have similar symptoms that include:
- Symptoms of colon polyps that usually do not occur in diverticulitis include:
- Decreased stool size
- Black stools
- The infolding (telescoping) of one segment of the intestine within another (intussusception), usually due to blockage of the intestine
- Iron deficiency
- Diverticulitis symptoms that usually do not occur in colon polyps include:
- Some colon polyps may become cancerous (less than 1%).
- Colon polyps do not cause diverticulitis or vice-versa; however, some researchers suggest that people with diverticulitis are at higher risk for developing colon polyps.
- Colon polyps have no known cause.
- Researchers and doctors believe that diverticulitis may related to, or caused by increased pressure in the large bowel due to hard stools and/or repeated straining when having a bowel movement, which causes the outpouching of the large bowel (diverticula) that entraps bacteria that stimulate inflammation.
What Are Colon Polyps? What Do They Look Like?
Colon polyps usually are benign, slow-growing tumors that arise from the epithelial cells in the large intestine. Some colon polyps contain and/or become cancerous tumors (malignant <1%). Benign colon polyps do not invade nearby tissue or spread to other parts of the body. They are commonly present in many individuals and increase in numbers with increasing age.
Picture of colon polpys and colon cancer (colorectal).
What Is Diverticulitis? What Does It Look Like?
Diverticula are marble-sized pouches in the wall of the digestive tract, Diverticula occur when the inner layer of the digestive tract bulges, which causes pouches, or a rupture occurs through weak spots in the outer layer of the digestive tract. (This is similar to what happens when an inner tube bulges through a tire.) These pouches can occur any place from the mouth to the anus, however, most occur in the large intestine (colon), especially the left-lower portion of the colon (just before the rectum). People who have these pouches have diverticulosis.
Diverticulosis usually does not cause symptoms so people do not know they have the condition.
Picture of diverticulitis, diverticulosis, diverticular disease
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Which Symptoms and Signs of Colon Polyps vs. Diverticulitis Are Different? Which Are the Same?
Colon Polyp Symptoms and Signs
Most people with colon polyps do not have signs or symptoms; however, when they do occur, the most common are:
- Rectal bleeding
- Diarrhea or constipation
- Decreased stool size (caliber)
- Other signs and symptoms may include
- Iron deficiency
- Black stools
- Abdominal pain
- Nausea and/or vomiting
- Intussusception (The colon folds into itself or telescopes causing intestinal blockage.)
Most people with colon polyps (also termed colonic polyps) have no pain.
Diverticulitis Symptoms and Signs
Most people with diverticulosis have no symptoms. When symptoms do occur, they are similar to the symptoms of many different digestive (gastrointestinal, (GI) diseases and problems. Therefore, the symptoms of diverticulosis does not mean that you have the condition. Call your doctor or other health-care professional if you have symptoms of diverticulitis.
When people with diverticulitis so have symptoms, they usually are mild and include:
- Pain in the belly (abdomen)
- Constipation (less often, diarrhea)
Diverticulitis is a more serious condition, and most people with it have symptoms and signs such as:
- Pain in the abdomen, usually in the lower left side
- Bleeding, bright red or maroon blood may appear in the stool, in the toilet (a symptom of rectal bleeding), or on the toilet paper. Bleeding is often mild and usually stops by itself; however, it can become severe.
If you do not treat diverticulitis right away, it can develop very serious complications. Symptoms of complications from diverticulitis include any of these symptoms:
- Worsening abdominal pain
- Persistent fever
- Vomiting (no food or liquid can be tolerated)
- Constipation for an extended period
- Burning or pain during urination
- Bleeding from the rectum
What Causes Colon Polyps? Can They Turn Into Cancer?
Yes, adenomas or adenomatous polyps have the potential to mutate into colon cancer); however, this does not happen often. Because it is difficult to tell the difference between small benign polyps and polyps that may mutate, gastroenterologists often will remove the polyps as a precaution during colonoscopy. The cause of colon polyps is not understood.
Can Colon Polyps Cause Diverticulitis?
No. Diverticulosis is thought to be caused by increased pressure on the intestinal wall from inside the intestine.
- As the body ages, the outer layer of the intestinal wall thickens. This causes the open space inside the intestine to narrow. Stool (feces) moves more slowly through the colon, increasing the pressure.
- Hard stools, such as those produced by a diet low in fiber or slower stool "transit time" through the colon can further increase the pressure.
- Frequent, repeated straining during bowel movements also increases the pressure and contributes to the formation of diverticula.
- Diverticulosis in developed countries usually due to a low fiber diet.
- Fruits and vegetables, whole grains, and legumes (beans, peas, and lentils contain fiber.
- There are two types of fiber, soluble (dissolves in water) and insoluble.
- Soluble fiber forms a soft gel-like substance in the digestive tract.
- Insoluble fiber passes through the digestive tract nearly unchanged.
- Insoluble and soluble fiber are necessary in the diet to keep stools soft and moving through the digestive tract easily. This is how fiber prevents constipation.
When to Call the Doctor for Colon Polyps vs. Diverticulitis Symptoms
Seek medical help if you have any of these symptoms because it may indicate a serious condition:
- Persistent abdominal pain, often in the lower-left area of the abdomen
- Persistent unexplained fevers
- Persistent diarrhea
- Persistent vomiting
- Persistent or recurring urinary tract infection
- If you are bleeding from the rectum, see a health-care professional as soon as possible.
- Seek medical care even if the bleeding stops on its own.
- Bleeding may be a sign of diverticulitis or other serious diseases.
- If there is a lot of blood or a steady flow of blood, go to a hospital emergency department immediately.
These symptoms suggest a complication of diverticulitis. If you have any of these, you should go to an Emergency Department immediately, but do not attempt to drive yourself. Call 911 or have someone drive you to the nearest hospital Emergency Department.
- Worsening abdominal pain
- Persistent fever with abdominal pain
- Vomiting so severe that food or liquids cannot be tolerated
- Swelling or distention of the abdomen
- Persistent constipation for an extended period
- Severe pain or other symptoms that you had before when you had diverticulitis
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