DIVERTICULAR COLONIC DISEASE Flashcards
terminology
sac-like protrusion of the colonic wall
What is a diverticulum?
Sac-like mucosal pouches that protrude from a tubular structure.
What are diverticula?
≥ 2 pouches are called diverticula.
What is diverticulosis?
The presence of one or more diverticula.
What is diverticulitis?
Inflammation with or without infection of a diverticulum.
What is diverticular disease?
Symptomatic diverticulosis.
Where can diverticula occur in the gastrointestinal tract?
Diverticula can occur at any point in the gastrointestinal tract (esophagus, stomach, small bowel, and colon).
What are colonic diverticula?
Sacciform protrusions outside the intestinal lumen, of varying size (mm-cm), which contain only mucosa and submucosa that herniate together through their own muscularis (acquired hernias of the mucous and submucosa), through the areas with low resistance of the intestinal wall, areas represented by the place where the blood vessels “vasa recta” penetrate, cross perpendicularly the colonic wall.
What does the term “diverticulosis” describe?
Describes the presence of multiple, non-inflamed diverticula
When is the term “diverticular disease” applied?
The term diverticular disease is applied to that condition in which diverticula are symptomatic, inflamed, or there are complications.
classification
true - congentital
false - acquired
What is the composition of true diverticula of the gastrointestinal (GI) tract?
True diverticula of the gastrointestinal (GI) tract contain all layers of the GI wall.
What is the composition of false or pseudo-diverticula?
False or pseudo-diverticula are mucosal and submucosal protrusions through the muscular wall of the bowel.
What are two examples of true diverticula?
Esophageal diverticula (Zenker diverticula) and Meckel diverticula are true diverticula
What is an example of a pseudo-diverticulum?
Colonic diverticula are pseudo-diverticula.
Where are solitary diverticula of the right colon typically located?
rare
Located at the level of the cecum or ascending colon, on the anterior face of the right colon, above the ileocecal valve.
What is the preferential location of false diverticula in the colon?
Preferential localization at the level of the sigmoid (95% of cases), only 4-5% at the level of another segment.
Damage to the sigmoid colon much more
frequently compared to other colon segments
What is a major dietary theory regarding the development of diverticula?
Deficiency in dietary fiber.
Western diet
Decreased fecal bulk
Narrowing of the colon
Small fecal mass
Increased intraluminal pressure needed to move material
What other factors are theorized to contribute to the development of diverticula?
Loss of tensile strength
Decrease in elasticity
What evidence supports the dietary fiber theory?
High fiber diet appears to decrease incidence.
Where are diverticula more likely to form in relation to muscle coverage?
Parietal areas relatively unprotected by muscles.
Why are diverticula rarely encountered in the rectum?
At the level of the rectum, where the longitudinal muscular layer comprises the entire circumference, diverticula are rarely encountered.
What other factor contributes to low resistance in the colonic wall, predisposing to diverticula formation?
Low resistance of the colonic wall at the place of penetration of nutrient vessels.
What is the primary factor related to the development of diverticula?
Related to an increase in intramural pressure.
What muscular change is often seen in association with diverticulosis?
Hypertrophy of muscular layers of the colonic wall is seen associated with diverticulosis.
Where in the colonic wall do diverticula typically occur (weakest areas)?
Adjacent to the vasa recta.
Mesenteric side of the colon.
What factors interplay in the pathogenesis of diverticulosis?
interrelation between the fibers in the diet, the structure of the colonic wall, and the intestinal motility.
How do fibers influence stool and colonic pressure?
Fibers increase the amount and volume of the stool by increasing the diameter of the colon and thus diminishing the contractility and intraluminal pressures.
Why is the sigmoid colon most commonly affected by diverticula?
The sigmoid colon has the smallest intraluminal diameter
What other factors are involved in the pathogenesis of diverticulosis?
Anomalies in the regulation of the extracellular colonic matrix, diminished intestinal transit as well as excessive contractility
What are the predisposing factors for diverticulosis?
Age
High fat/meat, low fiber diet
Decreased exercise
Connective tissue disorders
What are the predisposing factors for diverticulitis?
Constipation
Steroids
Where in the colon can diverticula form?
Diverticula form through the entire colon.
- Left colon
- Sigmoid colon (most common)
- Right-sided (uncommon)
▪ Classically Sigmoid
▪ Rectal Sparing
▪ Can occur anywhere
How is diverticular disease characterized?
Clinically significant and symptomatic diverticulosis.
What are the patterns of diverticular disease?
Isolated or recurrent
Uncomplicated or complicated
What is asymptomatic uncomplicated diverticular disease?
Refers to the presence of diverticulosis without any symptoms or complications of the disease.
Most often this is noted incidentally on colonoscopy or on radiological imaging.
What is recurrent symptomatic uncomplicated diverticular disease?
Refers to the above-mentioned symptoms of SUDD occurring multiple times during the year.
What is symptomatic uncomplicated diverticular disease (SUDD)?
Symptoms attributed to diverticulosis in the absence of any visible inflammation or diverticulitis.
Refers to episodes of abdominal pain without evidence of inflammation.
Classically, the pain will come and go but can also be constant in nature.
Symptoms may be relieved with flatus or bowel movements.
Associated symptoms include abdominal pain, bloating, constipation, and diarrhea.
Importantly, this condition does not include a history of acute diverticulitis.
What is segmental colitis associated with diverticulosis (SCAD)?
A chronic form of diverticulitis that can mimic inflammatory bowel disease (IBD) and has evidence of macroscopic inflammation in diverticula on colonoscopy.
Symptoms are often similar to IBD and include abdominal pain, diarrhea, and bleeding.
What are the different categories of diverticular disease?
Asymptomatic colon diverticulosis
Symptomatic uncomplicated disease
Recurrent symptomatic disease
Complicated disease
- Acute diverticulitis
- Diverticular hemorrhage
- Peridiverticular or remote abscess
- Perforations
- Purulent or fecaloid peritonitis
How do most patients with diverticulosis present?
Completely asymptomatic
What other gastrointestinal symptoms may be present in diverticular disease?
Meteorism influenced by defecation
Incomplete rectal discharge
Intestinal transit disorders (diarrhea / constipation)
Mucus in the stool
Where is pain typically located in diverticular disease?
Unsystematized pain in the left iliac fossa or in the suprapubic region
What are the paraclinical explorations used in the diagnosis of diverticular disease?
Simple abdominal x-ray (plain films)
Ultrasonography (US)
Abdominal-pelvic CT with contrast enhancement
Colonoscopy
Contrast enema examination (irrigoscopy/irrigography) single or double contrast
Tc-labeled erythrocyte scintigraphy
Selective mesenteric angiography
What radiological findings can suggest acute or chronic diverticulitis?
Changes in the mucosal surface, narrowing of the bowel, and absent motility in an area of the bowel known to be affected by diverticula.
What is a limitation of radiological examination in patients with diverticula?
Radiological examination by itself cannot definitively determine whether narrowing of the bowel (stenosis) in a patient with known diverticula is due to inflammation or whether it may actually be caused by a tumor
What is necessary for further work-up in cases where radiological findings are inconclusive?
In such cases, endoscopy (colonoscopy) with biopsy (tissue sampling) must be part of further work-up.
What information does contrast enema examination (irrigoscopy/irrigography) provide?
Existence, the number, and location of diverticula.
Small opaque formations that protrude from the intestinal contour delimited by the barium column.
When is contrast enema examination (irrigoscopy/irrigography) contraindicated?
IS NOT INDICATED IN THE EARLY PHASE OF AN EPISODE OF ACUTE DIVERTICULITIS.
Why is contrast enema examination (irrigoscopy/irrigography) contraindicated in acute diverticulitis?
There is a risk of perforation.
What type of contrast substance should be used in contrast enema examinations for diverticulitis, and why?
Only water-soluble contrast substance, such as GASTROFIN, should be used (less risky).
What kind of study should be performed, and when should it be terminated?
A gentle, single-contrast study should be performed and terminated once findings of diverticulitis are discovered.
What can irrigography reveal in cases of diverticulitis?
Irrigography can reveal extravasation trajectories of the substance through the perforation hole or deformation of the colonic wall, secondary to the inflammatory mass in the vicinity.
What are some findings on irrigography that suggest complications of diverticulitis?
Extravasated contrast material with or without the outlining of an abscess cavity.
An intramural sinus tract.
Fistula.
What can ultrasonography (US) visualize in cases of diverticulitis?
Can visualize the segments of the affected colon.
What are the ultrasound findings in the colonic wall in diverticulitis?
Hypoechoic thickening of the wall.
What does pericolic inflammation appear as on ultrasound?
Pericolic inflammation appears as a hyperechoic halo.
What other important role does ultrasound play in complicated diverticulitis?
The identification of local or distant abscesses that allows percutaneous drainage.
What complications of diverticulitis can be revealed by CT scans?
Ileus
Obstruction
Fistulas
What is the role of abdominal-pelvic CT with oral and IV contrast enhancement in the diagnosis of complicated diverticular disease (acute diverticulitis)?
Has become the method of choice for diagnosis of complicated diverticular disease (of acute diverticulitis) with a sensitivity and specificity of 97% and 100% respectively.
What are the indications for using CT in the evaluation of diverticular disease?
Acute phase of acute diverticulitis.
Suspicion of abscess or fistula.
Suspicion of right diverticulitis – differential diagnosis with colon cancer.
What are the characteristic imaging features of diverticulitis on CT?
Presence of diverticula with pericolic infiltration of fatty tissue (often appearing as fat stranding).
Thickening of the intestinal wall.
Phlegmon (formation of abscesses) and pericolic fluid.
When is colonoscopy indicated in diverticular disease?
Indication in uncomplicated diverticulosis.
When should colonoscopy be avoided?
It should be avoided in the acute stage (episode of acute diverticulitis) because air insufflation increases the risk of perforation.
risk of injuring the colon
When should colonoscopy be performed after an episode of acute diverticulitis?
After solving acute inflammation, once the acute phase has passed (one to three months later), it should be electively performed to exclude competing diagnoses, particularly malignancy.
Sometimes, inflamed diverticula cannot
What is an advantage of colonoscopy over radiologic examinations in patients with diverticular disease?
Intestinal polyps located in segments of the bowel affected by diverticula are also more reliably detected by endoscopy than by radiologic examinations.
If the distance between the polyp and the diverticular opening is sufficiently large, polyps can usually be safely removed during colonoscopy.
What are the indications for selective mesenteric angiography?
In the case of patients with massive digestive hemorrhage/bleeding.
X ray not useful in GI bleeding
What information does selective mesenteric angiography provide?
Specifies the location of the hemorrhage.
What interventions can be performed using selective mesenteric angiography?
Intraarterial injection of Vasopressin.
Selective arterial embolization.
What is the use of scintigraphy with erythrocyte marked with TECNETIUM (Tc) in diverticular hemorrhage?
Scintigraphy with erythrocyte marked with TECNETIUM (Tc) allows detecting the location of a diverticular hemorrhage.
▪ Diverticula are common coincidental findings of radiological or endoscopic
(colonoscopic) examinations.
▪ Symptoms of lower abdominal pain with fever and an increase in the white blood
cell count point to the possibility of acute diverticulitis, among other diagnoses.
What are the diagnostic circumstances in which diverticulosis is often discovered?
Incidentally – in people exposed to medical examinations for colorectal cancer screening or for the detection of occult blood loss.
What colonic symptoms may lead to the diagnosis of diverticular disease?
Colonic symptoms – pain in the left iliac fossa, bloating, constipation, diarrhea, rectal removal of mucus.
How else might diverticular disease be diagnosed?
The appearance of complications.
How is uncomplicated diverticular disease diagnosed?
Data provided by irrigography, CT, and/or colonoscopy.
What are the characteristic signs and symptoms of acute diverticulitis?
Sudden onset of an algic syndrome in the left or lower hemiabdomen.
Fever.
Transit disorders.
Palpation of a mass or local defense.
Inflammatory syndrome (increased CRP, leukocytosis).
Confirmation by CT and/or US.
What are the signs and symptoms of entero-bladder or entero-vaginal fistulas?
Pneumaturia or fecaluria.
Passage and elimination of feces and gases through the vagina.
What are the signs and symptoms of purulent and stercoral peritonitis?
Signs of diffuse peritoneal irritation.
Important inflammatory syndrome (marked increase in ESR, CRP), leukocytosis.
Bacteriological and cytological examination of the peritoneal fluid.
What are the characteristics of diverticular digestive hemorrhage?
Abrupt character.
How is the origin and location of diverticular hemorrhage specified?
Origin and headquarters specified by selective angiography and/or exploration with radioisotopes, colonoscopy (in case of moderate or spontaneously stopped bleeding).
What clinical conditions should be considered in the differential diagnosis of diverticular disease?
Irritable bowel syndrome
Colorectal cancer
Inflammatory bowel diseases
- Ulcerative colitis
- Crohn’s disease
Infectious colitis or irradiation
Ischemic colitis
Acute appendicitis
Angiodysplasia intestinal diseases
Anorectal diseases
COMPLICATION of DIVERTICULAR DISEASE
▪ INFLAMATION
▪ BLEEDING
▪ FISTULA
▪ OBSTRUCTION
▪ ABCESS
What is a serious complication that can occur due to a diverticulum?
Perforation of the affected diverticulum can occur, which may cause generalized peritonitis.
What is a more common outcome of diverticular perforation?
More commonly, however, a perforation is walled off by the greater omentum or pericolic fat, causing a diverticular abscess or sinus, which may in turn lead to fistula formation.
What can occur in chronic diverticular disease?
In chronic disease, fibrosis may also occur, leading to a benign stricture.
What vascular complication can occur in diverticular disease?
Hemorrhage can also occur from the nutrient vessel, which is always in close proximity to diverticulae.
Severe diverticulitis: inflamed colonic segment with congestion, edema and purulent exudates in the vicinity of a necrotic diverticulum
What is the underlying process in acute diverticulitis?
Is the consequence of a diverticulum becoming blocked, trapping bacteria, and subsequently developing inflammation.
How is acute diverticulitis classified?
uncomplicated or complicated.
What is the typical clinical presentation of uncomplicated diverticulitis?
The clinical presentation of uncomplicated diverticulitis is colicky abdominal pain that is relieved with flatus or a bowel movement.
What symptoms suggest complicated diverticulitis?
dysuria, urinary frequency, pneumaturia, fecaluria, and recurrent urinary infection concerning for colovesical fistula.
What is a common physical examination finding in uncomplicated diverticulitis?
left-lower-quadrant abdominal tenderness is often present.
Is rectal bleeding a common presentation of diverticulitis?
uncommon
Only 1/2 of the patients have leukocytosis so that a normal number of leukocytes
does not exclude the diagnosis
What are the possible outcomes of acute diverticulitis?
The evolution may be spontaneous towards remission or under conservative treatment.
How is the diagnosis of acute diverticulitis established?
The diagnosis is established on the basis of anamnesis and physical examination.
When are imaging techniques useful in acute diverticulitis?
In case of a diagnostic doubt it is useful to use imaging techniques.
What is the typical location and nature of pain in diverticulitis?
Typically located in the left lower quadrant.
Subacute and constant pain.
Can diverticulitis occur on the right side?
Yes, right-sided diverticulitis can occur (possibly congenital).
Is fever a common symptom of diverticulitis?
Almost invariably present.
When might a high-grade fever and sepsis occur in diverticulitis?
If perforation is not contained.
When the peritonitis is generalized.
What bowel changes might be reported by patients with diverticulitis?
Constipation or loose stools.
Is rectal bleeding a common symptom of diverticulitis?
Rectal bleeding is unusual.
What conditions should be considered when a patient presents with lower abdominal pain, fever, and bloody diarrhea?
differential diagnosis
Bacterial colitis (Shigella, Salmonella, Campylobacter)
Ischemic colitis
Inflammatory bowel disease
What conditions should be considered in the differential diagnosis of generalized peritonitis?
Acute abdomen
What should be considered when a patient presents with gynecologic disorders and pain localized to the left lower quadrant (LLQ)?
Diverticulitis
What conditions present with acute severe abdominal pain?
Perforation of an abdominal viscus (Peptic ulcer, Small bowel obstruction, Choledocholithiasis, Nephrolithiasis, Rupture and dissection of an abdominal aortic aneurysm)
