Gen Surg: Diverticular disease Flashcards
What is a diverticulum?
An outpouching of the gut wall, usually at sites of entry of perforating arteries
What does diverticulosis mean?
Presence of diverticula, no inflammation
What does diverticulitis mean?
Inflammation of a diverticulum - most often occuring when faeces obstruct the neck of the diverticulum causing stagnation and allowing bacteria to multiply and produce inflammation. This can then lead to bowel perforation (peridiverticulitis), abscess formation, fistulae into adjacent organs, or even generalized peritonitis.
Where do diverticula most commonly occur?
Along the lines where the penetrating colonic arteries thransverse the colonic wall between the taenia coli
What is diverticular disease?
Diverticula associated wtih abdominal pain and disrupted bowel habit (ie symptomatic)
What is meant by the term diverticular colitis?
Refers to cresenteric inflammation on the folds in areas of diverticulosis
What is thought to be the cause of diverticulosis?
Unknown
How do diverticula form?
There is thickening of the muscle layer and, because of high intraluminal pressures, pouches of mucosa extrude through the muscular wall through weakened areas near blood vessels to form diverticula.
An alternative explanation is cholinergic denervation with increasing age which leads to hypersensitivity and increased uncoordinated muscular contraction.
What are symptoms of diverticulosis?
Majority asymptomatic, but if painful diverticular disease (most commonly affects sigmoid colon):
- Altered bowel habit - constipation/flatulence
- Left sided colic relieved by defecation
- Rectal bleeding - can be massive
- Nausea
What are symptoms of diverticulitis?
Features of diverticulosis, plus:
- Pyrexia
- Tender bowels
- Localised/generalised peritoneal abdominal pain
- Rebound tenderness
- Constipation
Similar to features of acute appendicitis, but on the left hand side rather than the right
What would you find on examination of someone with diverticulitis?
Left side fo the abdomen
- Tenderness
- Guarding
- Rigidity
- Palpable tender mass - LIF
Where in the colon does diverticular disease most commonly affect?
Sigmoid colon
Why can severe pain and constipation occur in severe diverticulosis?
Due to luminal narrowing of the sigmoid colon
How is diverticulosis most commonly picked up?
Incidentaly on imaging
Why can some of those with diverticular disease present with blood in the stool?
Tends to be large volume, dark red clotted rectal blood - due to rupture of peridiverticular submucosal blood vessel
How would you investigate if you suspected diverticulosis?
- Elective barium enema (seen below) (gastrogaffin)
- Could consider colonoscopy + sigmoidoscopy - poor investigation for assessing number
- Consider CT scan
- CXR if perforation expected
How would you investigate someone for suspected acute diverticulitis?
- Bloods - FBC, CRP
- Abdo US
- CT colonography
What might you see on CT in someone with acute diverticulitis?
- Colonic wall thickening
- Diverticula
- Pericolic collections and abscesses
- Streaky increased density extending into the immediate pericolic fat
- Thickening of the pelvic fascial planes
What antibiotics would you use to treat diverticulitis?
3-7 days
- IV Gentamicin + Metranidazole +/- Amoxicillin (in pen allergic - co-trimoxazole)
- Switch to oral Metranidazole + doxycycline/Co-trimoxazole
What is a Meckel’s Diverticulum?
Meckel’s Diverticulum is a true congenital diverticulum - a slight bulge in the small intestine present at birth and a vestigial remnant of the omphalomesenteric duct (also called the vitelline duct or yolk stalk).
