Diverticular Disease Flashcards
What is diverticulum? Where are they found?
A diverticulum is an outpouching of the bowel wall.
They are most commonly found in the sigmoid colon, but can be present throughout the large and small bowel.
Briefly differentiate between diverticulosis, diverticular disease, diverticulitis and diverticular bleed
Diverticulosis- the presence of diverticula (asymptomatic, incidental on imaging)
Diverticular disease- symptoms arising from the diverticula
Diverticulitis- inflammation of the diverticula
Diverticular bleed- where the diverticulum erodes into a vessel and causes a large volume painless bleed
Briefly describe the prevalance of diverticulosis
Diverticulosis is present in around 50% of >50yrs and 70% of >80yrs, but only 25% of these cases become symptomatic.
The disease affects men more than women and is more prevalent in developed countries.
Briefly describe the pathophysiology of diverticular disease
In an aging bowel that has naturally become weakened over time, the movement of stool within the lumen will cause an increase in luminal pressure. This results in an outpouching of the mucosa through the weaker areas of the bowel wall (at the junctions of the triangular muscle sheets and blood vessels penetrate to supply the bowel wall).
Bacteria can overgrow within the outpouchings, leading to inflammation of the diverticulum (diverticulitis) which can sometimes perforate, potentially leading to diffuse peritonitis sepsis and death. In chronic cases, fistulae can form, most commonly colovesical or colovaginal.
What’s the difference between simple and complicated diverticulitis?
Diverticulitis is classified as either simple or complicated. Complicated diverticulitis refers to abscess presence or free perforation, whilst simple diverticulitis describes inflammation without these features.
What are the risk factors for formation of diverticulum?
The risk factors for the formation of diverticulum include age, low dietary fibre intake, obesity, smoking, family history, and NSAID use.
How does diverticulosis present?
A large proportion of individuals with diverticulosis remain asymptomatic and are only found incidentally, such as during routine colonoscopy or CT imaging. These are often of no clinical significance. However, patients can present with diverticular disease, diverticulitis or a diverticular bleed
How does diverticular disease present?
Features of diverticular disease include an intermittent lower abdominal pain, typically colicky in nature and may be relieved by defecation.
Other symptoms include an altered bowel habit, associated nausea and flatulence. There will be no systemic features present.
How does acute diverticulitis present?
Acute diverticulitis however will present with acute abdominal pain, typically sharp in nature and normally localised in the left iliac fossa pain, worsened by movement. On examination, there will be localised tenderness, alongside features of systemic upset, such as decreased appetite, pyrexia or nausea.
A perforated diverticulum will present with signs of localised peritonism or generalised peritonitis. These patients are frequently extremely unwell and the condition can often be fatal.
What are diverticular abscesses? How are they treated?
A diverticular abscess (often termed a pericolic abscess) occurs as a sequelae in complicated diverticulitis.
Those that are around <5cm can generally be managed with conservatively with intravenous antibiotics, as this is effective in ~90% of cases. If the abscess is any bigger, then radiological drainage is first-line treatment.
Complicated multi-loculated abscesses (or patients who clinically deteriorate) will need surgical intervention, either with a laparoscopic washout or a Hartmann’s procedure.
What investigations should be ordered for diverticular disease?
Note: laboratory
Any patient presenting acutely with suspected diverticular disease should have initial routine blood tests performed, including FBC, CRP, and U&Es. Consider a faecal calprotectin if the diagnosis is less clear.
Those with suspected diverticulitis, should also have a Group and Save and a venous blood gas. A urine dipstick may prove helpful to exclude any urological causes.
What investigations should be ordered in diverticular disease?
Note: imaging
For cases of suspected diverticulitis, a CT abdomen-pelvis scan is the investigation of choice. CT findings that can suggest diverticulitis include thickening of the colonic wall, pericolonic fat stranding, abscesses, localised air bubbles, or free air.
In patients with suspected uncomplicated diverticular disease, a flexible sigmoidoscopy is a good initial approach as this will identify any obvious rectosigmoidal lesion. If the patient is not a suitable candidate for endoscopy, CT colonography is an alternative option.
How does diverticular disease present on CT abdomen-pelvis?
CT abdomen-pelvis scan is the investigation of choice. CT findings that can suggest diverticulitis include thickening of the colonic wall, pericolonic fat stranding, abscesses, localised air bubbles or free air.
Why should a colonoscopy never be performed in a patient with suspected diverticulitis?
Colonoscopy should never be performed in any presenting cases of suspected diverticulitis, due to the increased risk of perforation.
What is shown in image A, B and C?
CT scan for varying degrees of diverticular disease (1) diverticulum in the sigmoid colon (2) degree of diverticulitis present (3) abscess formation, secondary to ongoing diverticulitis.
Briefly describe Hinchey Classification
Acute diverticulitis can be staged using the Hinchey Classification, a classification system based on CT findings. It can be used to aid clinical management; higher stages are associated with higher morbidity and mortality.
