Diverticulosis
Encyclopedia
Diverticulosis also known as "diverticular disease" is the condition of having diverticula
in the colon
, which are outpocketings of the colonic mucosa and submucosa through weaknesses of muscle
layers in the colon wall. These are more common in the sigmoid colon
, which is a common place for increased pressure. This is uncommon before the age of 40, and increases in incidence after that age.
Most people with colonic diverticulosis are unaware of this structural change. When symptoms do appear in a person over 40 years of age it is important to obtain medical advice and exclude more dangerous conditions such as cancer of the colon or rectum.
The clinical forms of colonic diverticulosis are
Symptoms can consist of (1) bloating, (2) changes in bowel movements (diarrhea or constipation), (3) Non-specific chronic discomfort in the lower left abdomen, with occasional acute episodes of sharper pain, (4) abdominal pain, often in the left lower abdomen and/or after meals. If these persist clinical investigation is advised.
.
First time bleeding from the rectum, especially in individuals aged over age 40, could be due to colon cancer, colonic polyps and inflammatory bowel disease rather than diverticulosis and requires clinical investigation.
The exact etiology
of colonic diverticulosis has yet to be fully clarified and many of the claims are only anecdotal.
The modern emphasis on the value of fiber in the diet began with Cleave. A strong case was made by Neil Painter and Adam Smith that a deficiency of dietary fiber is the cause of diverticular disease. They argued that the colonic muscles needed to contract strongly in order to transmit and expel the small stool associated with a fiber deficient diet. The increased pressure within the segmented section of bowel over years gave rise to herniation at the vulnerable point where blood vessels enter the colonic wall. Denis Burkitt had suggested that the mechanical properties of the colon may be different in the African and the European subjects. Because Africans eat a diet containing much more fiber than Europeans and use the natural squatting position for defecation, they pass bulky stools, and hence rarely if ever develop colonic diverticulosis. The U.S. National Institutes of Health (NIH) considers the fiber theory "unproven."
However, change in the strength of the colonic wall with age may be an aetiological factor. Connective tissue
is a significant contributor to the strength of the colonic wall. The mechanical properties of connective tissue depend on a wide variety of factors, the type of tissue and its age, the nature of the intramolecular and intermolecular covalent cross links and the quantity of the glycosaminoglycans associated with the collagen
fibrils. The submucosa of the colon is composed almost entirely of collagen, both type I and type III. Several layers of collagen fibres make up the submucosa of the human colon. The collagen fibril diameters and fibril counts are different between the left and right colon and change with age and in colonic diverticulosis,. The implication being that changes which are normally associated with ageing are more pronounced in colonic diverticulosis. Iwasaki found that the tensile strength of the Japanese colon obtained at postmortem declined with age. Similarly the mechanical properties of the colon are stronger in African than European subjects. However, this race-based claim is contradicted by the virtually identical incidence of diverticular disease in black and white Americans.
The strength of the colon decreases with age in all parts of the colon, except the ascending colon. The fall in tensile strength with age is due to a decrease in the integrity of connective tissue. Cross linkage of collagen is increased in colonic diverticulosis. The mucosal layer is possibly more elastic and it is likely that the stiffer external layers break and allow the elastic mucosa to herniate through forming a diverticulum. Collagen has intermolecular and intramolecular cross links which stabilise and give strength to the tissue in which it is located. Accumulation of covalently linked sugar molecules and related increasing cross linking products are found in a variety of tissues with ageing, skin, vascular tissue, the cordae tendinae of heart valves and the colon. This reduces the strength and pliability of the collagen. Colonic diverticulosis increases in frequency with age. There is a reduction in the strength of the colonic mucosa with age, and that increased contractions in the descending and sigmoid colon secondary to an insufficient fibre content of the diet cause protrusion through this weakened wall.
Colonic diverticulosis is in general a benign condition of the bowel which uncommonly becomes symptomatic and even less commonly becomes a truly clinical complicated problem.
While a good history is often sufficient to form a diagnosis of Diverticulosis or Diverticulitis, it is important to confirm the diagnosis and rule out other pathology (notably colorectal cancer) and complications.
Investigations
It is important to note that both Barium enema and Colonoscopy are contraindicated during acute episodes of diverticulitis, as the barium may leak out into the abdominal cavity, and colonoscopy can cause perforations of the bowel wall.
. The American Dietetic Association recommends 20-35 grams each day. Wheat bran has much to commend it as this has been shown to reduce intra colonic pressure
Ispaghula is also effective at 1-2 grams a day. Colonic stimulants should be avoided.
The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) says foods such as nuts, popcorn hulls, sunflower seeds, pumpkin seeds, caraway seeds, and sesame seeds have traditionally been labeled as problem foods for people with this condition; however, no scientific data exists to prove this hypothesis. The seeds in tomatoes, zucchini, cucumbers, strawberries, raspberries, and poppy seeds, are not considered harmful by the NIDDK. Treatments, like some colon cleansers, that cause hard stools, constipation, and straining, are not recommended.
Some doctors also recommend avoidance of fried foods, nuts, corn, and seeds to prevent complications of diverticulosis. Whether these diet restrictions are beneficial is uncertain; recent studies have stated that nuts and popcorn do not contribute positively or negatively to patients with diverticulosis or diverticular complications. When the spasm pain is troublesome the use of peppermint oil (1 drop in 50 ml water), or peppermint tablets (e.g., colpermin), can be helpful.
Complicated diverticulosis requires treatment of the complication. These complications are often grouped under a single diagnosis of diverticulitis
and require skilled medical care of the infection, bleeding and perforation which may include intensive antibiotic treatment, intravenous fluids and surgery. Complications are more common in patients who are taking NSAIDS or aspirin. As diverticulosis occurs in an older population such complications are serious events.
. This occurs in 10%-25% of people with diverticulosis (NIDDK website). Tears in the colon leading to bleeding or perforations may occur; intestinal obstruction may occur (constipation or diarrhea does not rule this possibility out); and peritonitis
, abscess
formation, retroperitoneal
fibrosis
, sepsis
, and fistula
formation are also possible occurrences. Rarely, an enterolith
may form.
Low fiber, high fat diet, constipation and use of stimulant laxatives increase the risk of bleeding, also history of diverticulitis increases the chance to bleed.
Infection of a diverticulum often occurs as a result of stool collecting in a diverticulum.
More than 10% of the U.S. population over the age of 40 and 50% over the age of 60 has diverticulosis. This disease is common in the U.S., Britain, Australia, Canada, and is uncommon in Asia and Africa. Large-mouth diverticula are associated with scleroderma
.
Diverticulum
A diverticulum is medical or biological term for an outpouching of a hollow structure in the body. Depending upon which layers of the structure are involved, they are described as being either true or false....
in the colon
Colon (anatomy)
The colon is the last part of the digestive system in most vertebrates; it extracts water and salt from solid wastes before they are eliminated from the body, and is the site in which flora-aided fermentation of unabsorbed material occurs. Unlike the small intestine, the colon does not play a...
, which are outpocketings of the colonic mucosa and submucosa through weaknesses of muscle
Muscle
Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
layers in the colon wall. These are more common in the sigmoid colon
Sigmoid colon
The sigmoid colon is the part of the large intestine that is closest to the rectum and anus. It forms a loop that averages about 40 cm...
, which is a common place for increased pressure. This is uncommon before the age of 40, and increases in incidence after that age.
Signs and symptoms
Cramps and tenderness in the affected areas.Most people with colonic diverticulosis are unaware of this structural change. When symptoms do appear in a person over 40 years of age it is important to obtain medical advice and exclude more dangerous conditions such as cancer of the colon or rectum.
The clinical forms of colonic diverticulosis are
Symptomatic colonic diverticulosis
This is the most common complication of colonic diverticulosis. This is when the motility (that is, the onward propulsive nature of contractions) of the bowel becomes disorganized. Sometimes, spasm can develop. This results in pain in the left lower abdomen and often is accompanied by the passage of small pellet-like stools and slime which relieves the pain.Symptoms can consist of (1) bloating, (2) changes in bowel movements (diarrhea or constipation), (3) Non-specific chronic discomfort in the lower left abdomen, with occasional acute episodes of sharper pain, (4) abdominal pain, often in the left lower abdomen and/or after meals. If these persist clinical investigation is advised.
Complicated colonic diverticulosis
This is very uncommon but highly dangerous. The diverticula may bleed, either rapidly (causing bleeding through the rectum) or slowly (causing anaemia). The diverticula can become infected and develop abscesses, or even perforate. These are serious complications and medical care is needed. Infected diverticula and development of abscesses merits the term diverticulitisDiverticulitis
Diverticulitis is a common digestive disease particularly found in the large intestine. Diverticulitis develops from diverticulosis, which involves the formation of pouches on the outside of the colon...
.
First time bleeding from the rectum, especially in individuals aged over age 40, could be due to colon cancer, colonic polyps and inflammatory bowel disease rather than diverticulosis and requires clinical investigation.
Risk factors
- increasing age
- constipation
- a diet that is low in dietary fiberDietary fiberDietary fiber, dietary fibre, or sometimes roughage is the indigestible portion of plant foods having two main components:* soluble fiber that is readily fermented in the colon into gases and physiologically active byproducts, and* insoluble fiber that is metabolically inert, absorbing water as it...
content or high in fat - high intake of meat and red meat
- connective tissue disorders (such as Marfan syndromeMarfan syndromeMarfan syndrome is a genetic disorder of the connective tissue. People with Marfan's tend to be unusually tall, with long limbs and long, thin fingers....
) that may cause weakness in the colon wall.
The exact etiology
Etiology
Etiology is the study of causation, or origination. The word is derived from the Greek , aitiologia, "giving a reason for" ....
of colonic diverticulosis has yet to be fully clarified and many of the claims are only anecdotal.
The modern emphasis on the value of fiber in the diet began with Cleave. A strong case was made by Neil Painter and Adam Smith that a deficiency of dietary fiber is the cause of diverticular disease. They argued that the colonic muscles needed to contract strongly in order to transmit and expel the small stool associated with a fiber deficient diet. The increased pressure within the segmented section of bowel over years gave rise to herniation at the vulnerable point where blood vessels enter the colonic wall. Denis Burkitt had suggested that the mechanical properties of the colon may be different in the African and the European subjects. Because Africans eat a diet containing much more fiber than Europeans and use the natural squatting position for defecation, they pass bulky stools, and hence rarely if ever develop colonic diverticulosis. The U.S. National Institutes of Health (NIH) considers the fiber theory "unproven."
However, change in the strength of the colonic wall with age may be an aetiological factor. Connective tissue
Connective tissue
"Connective tissue" is a fibrous tissue. It is one of the four traditional classes of tissues . Connective Tissue is found throughout the body.In fact the whole framework of the skeleton and the different specialized connective tissues from the crown of the head to the toes determine the form of...
is a significant contributor to the strength of the colonic wall. The mechanical properties of connective tissue depend on a wide variety of factors, the type of tissue and its age, the nature of the intramolecular and intermolecular covalent cross links and the quantity of the glycosaminoglycans associated with the collagen
Collagen
Collagen is a group of naturally occurring proteins found in animals, especially in the flesh and connective tissues of mammals. It is the main component of connective tissue, and is the most abundant protein in mammals, making up about 25% to 35% of the whole-body protein content...
fibrils. The submucosa of the colon is composed almost entirely of collagen, both type I and type III. Several layers of collagen fibres make up the submucosa of the human colon. The collagen fibril diameters and fibril counts are different between the left and right colon and change with age and in colonic diverticulosis,. The implication being that changes which are normally associated with ageing are more pronounced in colonic diverticulosis. Iwasaki found that the tensile strength of the Japanese colon obtained at postmortem declined with age. Similarly the mechanical properties of the colon are stronger in African than European subjects. However, this race-based claim is contradicted by the virtually identical incidence of diverticular disease in black and white Americans.
The strength of the colon decreases with age in all parts of the colon, except the ascending colon. The fall in tensile strength with age is due to a decrease in the integrity of connective tissue. Cross linkage of collagen is increased in colonic diverticulosis. The mucosal layer is possibly more elastic and it is likely that the stiffer external layers break and allow the elastic mucosa to herniate through forming a diverticulum. Collagen has intermolecular and intramolecular cross links which stabilise and give strength to the tissue in which it is located. Accumulation of covalently linked sugar molecules and related increasing cross linking products are found in a variety of tissues with ageing, skin, vascular tissue, the cordae tendinae of heart valves and the colon. This reduces the strength and pliability of the collagen. Colonic diverticulosis increases in frequency with age. There is a reduction in the strength of the colonic mucosa with age, and that increased contractions in the descending and sigmoid colon secondary to an insufficient fibre content of the diet cause protrusion through this weakened wall.
Colonic diverticulosis is in general a benign condition of the bowel which uncommonly becomes symptomatic and even less commonly becomes a truly clinical complicated problem.
Diagnosis
In cases of asymptomatic Diverticulosis, the diagnosis is usually made as an incidental finding on other investigations.While a good history is often sufficient to form a diagnosis of Diverticulosis or Diverticulitis, it is important to confirm the diagnosis and rule out other pathology (notably colorectal cancer) and complications.
Investigations
- Plain Abdominal X-ray may show signs of a thickened wall, ileus, constipation, small bowel obstruction or free air in the case of perforation. Plain X-rays are insufficient to diagnose Diverticular Disease.
- Contrast CT is the investigation of choice in acute episodes of Diverticulitis and where complications exist.
- Colonoscopy will show the diverticulum and rule out malignancy. A Colonoscopy should be performed 4–6 weeks after an acute episode.
- Barium enema is inferior to colonoscopy in terms of image quality and is usually only performed if the patient has strictures or an excessively tortuous sigmoid colon where colonoscopy is difficult or dangerous.
- MRI provides a clear picture of the soft tissue of the abdomen, however its expense often outweighs the benefits when compared to contrast CT or colonoscopy.
- There is no blood test for Diverticulosis.
It is important to note that both Barium enema and Colonoscopy are contraindicated during acute episodes of diverticulitis, as the barium may leak out into the abdominal cavity, and colonoscopy can cause perforations of the bowel wall.
Management
Many patients with diverticulosis have minimal to no symptoms, and do not require any specific treatment. A high-fiber diet and fiber supplements are advisable to prevent constipation .. The American Dietetic Association recommends 20-35 grams each day. Wheat bran has much to commend it as this has been shown to reduce intra colonic pressure
Ispaghula is also effective at 1-2 grams a day. Colonic stimulants should be avoided.
The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) says foods such as nuts, popcorn hulls, sunflower seeds, pumpkin seeds, caraway seeds, and sesame seeds have traditionally been labeled as problem foods for people with this condition; however, no scientific data exists to prove this hypothesis. The seeds in tomatoes, zucchini, cucumbers, strawberries, raspberries, and poppy seeds, are not considered harmful by the NIDDK. Treatments, like some colon cleansers, that cause hard stools, constipation, and straining, are not recommended.
Some doctors also recommend avoidance of fried foods, nuts, corn, and seeds to prevent complications of diverticulosis. Whether these diet restrictions are beneficial is uncertain; recent studies have stated that nuts and popcorn do not contribute positively or negatively to patients with diverticulosis or diverticular complications. When the spasm pain is troublesome the use of peppermint oil (1 drop in 50 ml water), or peppermint tablets (e.g., colpermin), can be helpful.
Complicated diverticulosis requires treatment of the complication. These complications are often grouped under a single diagnosis of diverticulitis
Diverticulitis
Diverticulitis is a common digestive disease particularly found in the large intestine. Diverticulitis develops from diverticulosis, which involves the formation of pouches on the outside of the colon...
and require skilled medical care of the infection, bleeding and perforation which may include intensive antibiotic treatment, intravenous fluids and surgery. Complications are more common in patients who are taking NSAIDS or aspirin. As diverticulosis occurs in an older population such complications are serious events.
Complications
Infection of a diverticulum can result in diverticulitisDiverticulitis
Diverticulitis is a common digestive disease particularly found in the large intestine. Diverticulitis develops from diverticulosis, which involves the formation of pouches on the outside of the colon...
. This occurs in 10%-25% of people with diverticulosis (NIDDK website). Tears in the colon leading to bleeding or perforations may occur; intestinal obstruction may occur (constipation or diarrhea does not rule this possibility out); and peritonitis
Peritonitis
Peritonitis is an inflammation of the peritoneum, the serous membrane that lines part of the abdominal cavity and viscera. Peritonitis may be localised or generalised, and may result from infection or from a non-infectious process.-Abdominal pain and tenderness:The main manifestations of...
, abscess
Abscess
An abscess is a collection of pus that has accumulated in a cavity formed by the tissue in which the pus resides due to an infectious process or other foreign materials...
formation, retroperitoneal
Retroperitoneum
The retroperitoneal space is the anatomical space in the abdominal cavity behind the peritoneum. It has no specific delineating anatomical structures...
fibrosis
Fibrosis
Fibrosis is the formation of excess fibrous connective tissue in an organ or tissue in a reparative or reactive process. This is as opposed to formation of fibrous tissue as a normal constituent of an organ or tissue...
, sepsis
Sepsis
Sepsis is a potentially deadly medical condition that is characterized by a whole-body inflammatory state and the presence of a known or suspected infection. The body may develop this inflammatory response by the immune system to microbes in the blood, urine, lungs, skin, or other tissues...
, and fistula
Fistula
In medicine, a fistula is an abnormal connection or passageway between two epithelium-lined organs or vessels that normally do not connect. It is generally a disease condition, but a fistula may be surgically created for therapeutic reasons.-Locations:Fistulas can develop in various parts of the...
formation are also possible occurrences. Rarely, an enterolith
Enterolith
An enterolith is a mineral concretion or calculus formed anywhere in the gastrointestinal system. Enteroliths are uncommon and usually incidental findings but, once found, they require at a minimum watchful waiting...
may form.
Low fiber, high fat diet, constipation and use of stimulant laxatives increase the risk of bleeding, also history of diverticulitis increases the chance to bleed.
Infection of a diverticulum often occurs as a result of stool collecting in a diverticulum.
More than 10% of the U.S. population over the age of 40 and 50% over the age of 60 has diverticulosis. This disease is common in the U.S., Britain, Australia, Canada, and is uncommon in Asia and Africa. Large-mouth diverticula are associated with scleroderma
Scleroderma
Systemic sclerosis or systemic scleroderma is a systemic autoimmune disease or systemic connective tissue disease that is a subtype of scleroderma.-Skin symptoms:...
.
External links
- Diverticular Resource Website
- Diverticulosis - PrimeHealthChannel