Diverticulosis

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Diverticulosis
Diverticulosis (two diverticula) 01.svg
Diverticulosis as seen endoscopically
Specialty General surgery

Diverticulosis is the condition of having multiple pouches (diverticula) in the colon that are not inflamed. These are outpockets of the colonic mucosa and submucosa through weaknesses of muscle layers in the colon wall. [1] Diverticula do not cause symptoms in most people. [2] Diverticular disease occurs when diverticula become clinically inflamed, a condition known as diverticulitis. [3]

Contents

Diverticula typically occur in the sigmoid colon, which is commonplace for increased pressure. The left side of the colon is more commonly affected in the United States while the right side is more commonly affected in Asia. [4] Diagnosis is often during routine colonoscopy or as an incidental finding during CT scan. [2]

It is common in Western countries with about half of those over the age of 60 affected in Canada and the United States. [4] Diverticula are uncommon before the age of 40, and increase in incidence beyond that age. [5] Rates are lower in Africa; [4] the reasons for this remain unclear but may involve the greater prevalence of a high fiber diet in contrast with the lower-fiber diet characteristic of many Western populations. [6]

Signs and symptoms

Diverticulosis in the sigmoid colon of a 70-year-old Colon diverticulum.jpg
Diverticulosis in the sigmoid colon of a 70-year-old

Some people with diverticulosis complain of symptoms such as cramping, bloating, flatulence, and irregular defecation. However, it is unclear if these symptoms are attributable to the underlying diverticulosis or to coexistent irritable bowel syndrome. [7]

Diverticular disease was found associated with a higher risk of left sided colon cancer. [8]

Bleeding

Diverticular disease can present with painless rectal bleeding as bright red blood per rectum. Diverticular bleeding is the most common cause of acute lower gastrointestinal bleeding. [9] However, it is estimated that 80% of these cases are self-limiting and require no specific therapy. [10]

Diverticulitis

Infection of a diverticulum can result in diverticulitis. A 2013 study [11] found that it happens only about 4% of the time. That contradicts the prevailing thinking that 10% to 25% of people with diverticulosis go on to develop diverticulitis. 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. Infection of a diverticulum often occurs as a result of stool collecting in a diverticulum.

Diverticulitis is defined as diverticular disease with signs and symptoms of diverticular inflammation. Clinical features of acute diverticulitis include constant abdominal pain, localized abdominal tenderness in the left lower quadrant of the abdomen, nausea, vomiting, constipation or diarrhea, fever and leukocytosis. [12]

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. [13] [14] [15] [16]

Segmental colitis associated with diverticulosis

Segmental colitis associated with diverticulosis (SCAD) is a condition characterized by localized inflammation of the colon between diverticula (interdiverticular mucosa) while sparing the diverticular orifices. SCAD may lead to abdominal pain, especially in the left lower quadrant, intermittent rectal bleeding, and chronic diarrhea.

Causes

Diet

The U.S. National Institutes of Health notes that, although the low-fiber theory of the cause of diverticulosis is the leading theory, it has not yet been proven. [17]

Genetics

The predisposition to diverticulosis for specific individuals is likely explained by a genetic component, a theory that is supported by studies examining the rates of diverticulosis among twins. [1] The heritability of diverticulosis is estimated to be approximately 40%. [1]

Intestinal motility

Another theory suggests the degeneration of glial neurons in the myenteric plexus and the interstitial cells of Cajal lead to slowed intestinal movement and consequently fecal content exerts increased pressure on the colon wall resulting in the formation of diverticula. [1]

Risk factors

  1. Advanced age
  2. constipation
  3. a diet that is low in dietary fiber (although this claim is controversial)
  4. connective tissue disorders (such as Marfan syndrome and Ehlers–Danlos syndrome) that may cause weakness in the colon wall
  5. hereditary or genetic predisposition, [18]
  6. extreme weight loss
  7. heavy meat consumption [19] [20] [21]

Pathophysiology

Drawing showing a sigmoid colon with many diverticula Sigmoid diverticulum (diagram).jpg
Drawing showing a sigmoid colon with many diverticula

The precise mechanisms by which diverticula are formed are unknown. [1] Multiple theories have been proposed including genetic susceptibility, diet, intestinal motility, changes in the microbiome, and inflammation. One leading theory suggests that diverticula form in weakened areas of the colon wall that are subjected to increased pressure. [1] The strength of the colon wall is known to decrease with age. [1] Previous theories proposed that impacted fecal matter and certain foods would get stuck in diverticula (thereby causing trauma), which caused poor blood flow, death of the affected intestinal wall cells, and intestinal perforation. [1] Newer theories have called this paradigm into question. [1]

Diagnosis

CT scan showing extensive diverticulosis of the sigmoid colon Sigmadivertikulose CT axial.jpg
CT scan showing extensive diverticulosis of the sigmoid colon
Diverticular disease DivertDiseaseMark.png
Diverticular disease
Whole slide of a transverse section of the left colon with diverticulosis Colon diverticulosis whole slide.jpg
Whole slide of a transverse section of the left colon with diverticulosis

Diverticulosis is defined by the presence of multiple pouches (diverticula) in the colon. [22] In people without symptoms, these are usually found incidentally during other investigations.[ citation needed ]

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.

Imaging

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 people with diverticulosis have minimal to no symptoms and do not require any specific treatment. Colonic stimulants should be avoided. Treatments, like some colon cleansers, that cause hard stools, constipation, and straining, are not recommended.[ citation needed ]

Diet

A high-fiber diet and fiber supplements are advisable to prevent constipation. [23] [24] The American Dietetic Association recommends 20–35 grams each day. Wheat bran has been shown to reduce intra colonic pressure. [25] [26]

The US 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. [2]

One study found that nuts and popcorn do not contribute positively or negatively to patients with diverticulosis or diverticular complications. [27] [28]

Complications

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.[ citation needed ]

Epidemiology

The prevalence of diverticulosis progressively increases with age. Approximately 50% of people over the age of 60 and 70% of people over the age of 80 have diverticulosis. [1] This disease is common in the U.S., Britain, Australia, Canada, and is uncommon in Asia and Africa. [5] Large-mouth diverticula are associated with scleroderma. Diverticular disease is more common in collagen disorders such as Ehlers–Danlos syndrome. [29]

History

The modern emphasis on the value of fiber in the diet began with Thomas L. Cleave. [30] A strong case was made by Neil Painter [31] and Adam Smith [32] 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 the bowel over years gave rise to herniation at the vulnerable point where blood vessels enter the colonic wall.

Society and culture

Economics

"The complications of diverticulosis cause considerable morbidity in the United States; health care expenditures for this disorder are estimated to be $2.5 billion per year." [33]

See also

Related Research Articles

<span class="mw-page-title-main">Defecation</span> Expulsion of feces from the digestive tract

Defecation follows digestion, and is a necessary process by which organisms eliminate a solid, semisolid, or liquid waste material known as feces from the digestive tract via the anus or cloaca. The act has a variety of names ranging from the common, like pooping or crapping, to the technical, e.g. bowel movement, to the obscene (shitting), to the euphemistic, to the juvenile. The topic, usually avoided in polite company, can become the basis for some potty humor.

<span class="mw-page-title-main">Constipation</span> Bowel dysfunction

Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel movement. Complications from constipation may include hemorrhoids, anal fissure or fecal impaction. The normal frequency of bowel movements in adults is between three per day and three per week. Babies often have three to four bowel movements per day while young children typically have two to three per day.

<span class="mw-page-title-main">Colonoscopy</span> Examination of the bowel

Colonoscopy or coloscopy is a medical procedure involving the endoscopic examination of the large bowel (colon) and the distal portion of the small bowel. This examination is performed using either a CCD camera or a fiber optic camera, which is mounted on a flexible tube and passed through the anus.

<span class="mw-page-title-main">Diverticulitis</span> Digestive disease of the large intestine

Diverticulitis, also called colonic diverticulitis, is a gastrointestinal disease characterized by inflammation of abnormal pouches—diverticula—that can develop in the wall of the large intestine. Symptoms typically include lower abdominal pain of sudden onset, but the onset may also occur over a few days. There may also be nausea, diarrhea or constipation. Fever or blood in the stool suggests a complication. People may experience a single attack, repeated attacks, or ongoing "smouldering" diverticulitis.

<span class="mw-page-title-main">Meckel's diverticulum</span> Medical condition

A Meckel's diverticulum, a true congenital diverticulum, is a slight bulge in the small intestine present at birth and a vestigial remnant of the vitelline duct. It is the most common malformation of the gastrointestinal tract and is present in approximately 2% of the population, with males more frequently experiencing symptoms.

<span class="mw-page-title-main">Diverticulum</span> Medical or biological term for an outpouching of a hollow (or a fluid-filled) structure in the body

In medicine or biology, a diverticulum is an outpouching of a hollow structure in the body. Depending upon which layers of the structure are involved, diverticula are described as being either true or false.

<span class="mw-page-title-main">Volvulus</span> Twisting of part of the intestine, causing a bowel obstruction

A volvulus is when a loop of intestine twists around itself and the mesentery that supports it, resulting in a bowel obstruction. Symptoms include abdominal pain, abdominal bloating, vomiting, constipation, and bloody stool. Onset of symptoms may be rapid or more gradual. The mesentery may become so tightly twisted that blood flow to part of the intestine is cut off, resulting in ischemic bowel. In this situation there may be fever or significant pain when the abdomen is touched.

<span class="mw-page-title-main">Fecal impaction</span> Medical condition

A fecal impaction or an impacted bowel is a solid, immobile bulk of feces that can develop in the rectum as a result of chronic constipation. Fecal impaction is a common result of neurogenic bowel dysfunction and causes immense discomfort and pain. Its treatment includes laxatives, enemas, and pulsed irrigation evacuation (PIE) as well as digital removal. It is not a condition that resolves without direct treatment.

<span class="mw-page-title-main">Diverticular disease</span> Problems arising from pouch formations in the large intestinal wall

Diverticular disease is when problems occur due to diverticulosis, a benign condition defined by the formation of pouches (diverticula) from weak spots in the wall of the large intestine. This disease spectrum includes diverticulitis, symptomatic uncomplicated diverticular disease (SUDD), and segmental colitis associated with diverticulosis (SCAD). The most common symptoms across the disease spectrum are abdominal pain and bowel habit changes such as diarrhea or constipation. Otherwise, diverticulitis presents with systemic symptoms such as fever and elevated white blood cell count whereas SUDD and SCAD do not. Treatment ranges from conservative bowel rest to medications such as antibiotics, antispasmodics, acetaminophen, mesalamine, rifaximin, and corticosteroids depending on the specific conditions.

<span class="mw-page-title-main">Gastrointestinal perforation</span> Hole in the wall of the gastrointestinal tract

Gastrointestinal perforation, also known as gastrointestinal rupture, is a hole in the wall of the gastrointestinal tract. The gastrointestinal tract is composed of hollow digestive organs leading from the mouth to the anus. Symptoms of gastrointestinal perforation commonly include severe abdominal pain, nausea, and vomiting. Complications include a painful inflammation of the inner lining of the abdominal wall and sepsis.

Abdominal bloating is a short-term disease that affects the gastrointestinal tract. Bloating is generally characterized by an excess buildup of gas, air or fluids in the stomach. A person may have feelings of tightness, pressure or fullness in the stomach; it may or may not be accompanied by a visibly distended abdomen. Bloating can affect anyone of any age range and is usually self-diagnosed, in most cases does not require serious medical attention or treatment. Although this term is usually used interchangeably with abdominal distension, these symptoms probably have different pathophysiological processes, which are not fully understood.

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. If there is evidence of complications, they must be removed. An enterolith may form around a nidus, a small foreign object such as a seed, pebble, or piece of twine that serves as an irritant. In this respect, an enterolith forms by a process similar to the creation of a pearl. An enterolith is not to be confused with a gastrolith, which helps digestion.

<span class="mw-page-title-main">Blood in stool</span> Medical condition

Blood in stool looks different depending on how early it enters the digestive tract—and thus how much digestive action it has been exposed to—and how much there is. The term can refer either to melena, with a black appearance, typically originating from upper gastrointestinal bleeding; or to hematochezia, with a red color, typically originating from lower gastrointestinal bleeding. Evaluation of the blood found in stool depends on its characteristics, in terms of color, quantity and other features, which can point to its source, however, more serious conditions can present with a mixed picture, or with the form of bleeding that is found in another section of the tract. The term "blood in stool" is usually only used to describe visible blood, and not fecal occult blood, which is found only after physical examination and chemical laboratory testing.

A low-residue diet is a diet intended to reduce certain constituents of the bowel, often with consequence for functional behaviour of the bowel. It may be prescribed for patients with ailments or functional gastrointestinal disorders mitigated by fewer and smaller bowel movements each day.

<span class="mw-page-title-main">Lower gastrointestinal bleeding</span> Medical condition

Lower gastrointestinal bleeding (LGIB) is any form of gastrointestinal bleeding in the lower gastrointestinal tract. LGIB is a common reason for seeking medical attention at a hospital's emergency department. LGIB accounts for 30–40% of all gastrointestinal bleeding and is less common than upper gastrointestinal bleeding (UGIB). It is estimated that UGIB accounts for 100–200 per 100,000 cases versus 20–27 per 100,000 cases for LGIB. Approximately 85% of lower gastrointestinal bleeding involves the large intestine, 10% are from bleeds that are actually upper gastrointestinal bleeds, and 3–5% involve the small intestine.

Stercoral ulcer is an ulcer of the colon due to pressure and irritation resulting from severe, prolonged constipation due to a large bowel obstruction, damage to the autonomic nervous system, or stercoral colitis. It is most commonly located in the sigmoid colon and rectum. Prolonged constipation leads to production of fecaliths, leading to possible progression into a fecaloma. These hard lumps irritate the rectum and lead to the formation of these ulcers. It results in fresh bleeding per rectum. These ulcers may be seen on imaging, such as a CT scan but are more commonly identified using endoscopy, usually a colonoscopy. Treatment modalities can include both surgical and non-surgical techniques.

Hinchey Classification is used to describe perforations of the colon due to diverticulitis. The classification was developed by Dr. E John Hinchey (1934–present), a general surgeon at the Montreal General Hospital and professor of surgery at McGill University.

Fibre supplements are considered to be a form of a subgroup of functional dietary fibre, and in the United States are defined by the Institute of Medicine (IOM). According to the IOM, functional fibre "consists of isolated, non-digestible carbohydrates that have beneficial physiological effects in humans".

<span class="mw-page-title-main">Colonic ulcer</span> Medical condition

Colonic ulcer can occur at any age, in children however they are rare. Most common symptoms are abdominal pain and hematochezia.

<span class="mw-page-title-main">Segmental colitis associated with diverticulosis</span> Medical condition

Segmental colitis associated with diverticulosis (SCAD) is a condition characterized by localized inflammation in the colon, which spares the rectum and is associated with multiple sac-like protrusions or pouches in the wall of the colon (diverticulosis). Unlike diverticulitis, SCAD involves inflammation of the colon between diverticula, while sparing the diverticular orifices. SCAD may lead to abdominal pain, especially in the left lower quadrant, intermittent rectal bleeding and chronic diarrhea.

References

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