GI + Colorectal 2 Flashcards
What are diverticula
Diverticula are small, bulging pouches that can form in the lining of your digestive system
Occur due to hypertrophy of the muscle propria, with diverticula then occurring at sites of potential weakness in the bowel wall (entry points of blood vessels)
This creates a ‘true’ diverticulum of just mucosa, without the muscular covering (as opposed to Meckel’s)
What is diverticulosis?
The presence of diverticula
What is diverticulitis?
The inflammation of diverticula
What is diverticular disease?
Symptomatic diverticula
Where are diverticula commonly found?
In the sigmoid, with 95% of the complications arising at this site
What are the causes of diverticula?
Low fibre diet (hard stools and thus higher pressure needed to move them)
Rarer associations: Marfans, Ehler’s Danlos syndrome and PKD
What are the clinical features of diverticular disease?
Mimic carcinoma of the colon:
Left sided colic, relieved by defecation
Altered bowel habit - including blood and mucus passage
Nausea
Flatulence
Severe pain and constipation if severe (causing lumina narrowing)
What investigations should be done for diverticular disease?
PR - may reveal pelvic abscess or colorectal cancer - main ddx
Sigmoidoscopy / Colonoscopy
Barium enema
CT
what is the management of diverticular disease?
Mebeverine = 1st kline medical management
What are the clinical features of Diverticulitis (infection)
Infection due to stagnation of the contents of teh diverticula
Severe left sided colic
Constipation (or overflow diarrhoea)
Symptoms mimicking appendicitis but on the left
What are the signs of diverticulitis?
Fever + tachycardia
Tenderness, guarding and rigidity on the left hand side
Can be a palpable mass in the LIF
Raised WCC and inflammatory markers
What is the management of diverticulitis?
Mild Attacks - low grade fever:
Bowel rest (fluids only) at home
Oral co-amoxiclav +/- metronidazole
Severe attacks (complicated - high grade fever)
Admit if pain cannot be controlled, or oral fluids not tolerated
Give analgesia, IV fluids, IV cefuroxime and metronidazole and keep NBM
Order erect CXR, AXR and contrast CT to assess for complications
DO not scope in acute attack
What complications can arise from diverticulitis?
Perforation Bleeding Stricutre Abscess Fistula
What does perforation lead to following diverticulitis?
Formation of paracolic or pelvic abscess, fistulae or generalised peritonitis
Presents with ileus +/- shock
Mortality = up to 40%
Management is with laparotomy +/- Hartman’s procedure
What is the presentation and management of abscess formation following diverticular disease?
Swinging fever, leucocytosis and localising signs (e.g. a boggy rectal mass)
Should be drained under CT guidance
How does bleeding following diverticular disease present?
Sudden, painless bleeding and also chronic occult loss, as a result of erosion of vessels at the fundus of the diverticulum
Large volumes can be lost, requiring transfusion
These often stop with bed rest
If they do not stop, locate the bleeding point via angiography (or colonoscopy) and then treat with embolisation (surgery rare)
Adrenaline injections and diathermy may negate the need for surgery
What kind of fistulas can form following diverticular disease?
Colovesical - leading to UTI and pneumaturia
Colovaginal - leading to foul discharge
Where does intestinal obstruction most commonly occur following diverticular disease?
Most commonly in the sigmoid after repeated episodes of diverticulitis
Chronic inflammation leads to scarring and the formation of a diverticular mass, which causes obstruction and may mimic colonic carcinoma
What is the management of asymptomatic diverticula of the colon?
Dietary advice is required for asymptomatic diverticulae
Increase unprocessed food intake and dietary fibre intake as part of a balanced diet (>20g/day of insoluble fibre)
What is the management in patients with uncomplicated by symptomatic diverticula disease?
Mebeverine first line
If there is very severe or recurrent diverticulitis, surgery may be considered
Rarely resorted to, complication rates are high
What are the indications for surgery in diverticular disease?
Small confined pericolonic abscess rarely require surgery
Any generalised peritonitis will require surgery
Emergency colonic resection required in massive haemorrhage / perforation
What are the risk factors of colorectal carcinoma?
Family history (+FAP/HNPCC) Age Western diet - low in fibre, high in fats - exercise, obesity UC (Chron's if it is in the colon) Smoking
POLYPS
What are the protective factors against colorectal carcinoma?
Fruit and vegetables / fibre consumption
Exercise
HRT
Aspirin / NSAIDs
Which gene is related to colorectal cancer?
Hereditary non-polyposis colorectal cancer (HNPCC) is responsible for <5% = arises from germline mutations in mismatch repair genes
Familial adenomatous polyposis (FAP) is responsible for <1% cancers, and occurs due to tumour suppressor gene APC mutations