Colorectal Flashcards
What are the 4 types of fistula?
- Enterocutaneous (intestine - skin)
- Enteroenteric/enterocolic (large/small intestine)
- Enterovaginal
- Enterovesical (bladder)
When to suspect an enterocutaneous fistula?
if there is excessive drainage and bubbles
Pus
If there is any uncertainty, methylene blue can be given. If methylene blue is found in the drain, this confirms a fistula.
Difference between high and low output enterocutaneous fistulas?
high (>500ml) or low output (<250ml)
Difference between duodenal/jejunal fistulas and colo-cutaneous fistulas?
Duodenal /jejunal fistulae -high volume, electrolyte rich secretions which can lead to severe excoriation of the skin
Colo-cutaneous fistulae will tend to leak faeculent material
Sequelae of enteroenteric/enterocolic fistula?
bacterial overgrowth may precipitate malabsorption syndromes
Main principles of fistula management?
- Normally heal spontaneously provided no IBD/distal obstruction
- Protect overlying skin if skin involvement with a fitted stoma bag
- In high output use ocrreotide to reduce the volume of pancreatic secretions
- Nutritional complications are common especially with high fistula (e.g. high jejunal or duodenal) these may necessitate the use of TPN
- When managing perianal fistulae surgeons should avoid probing the fistula where acute inflammation is present
- W hen perianal fistulae occur secondary to Crohn’s disease the best management option is often to drain acute sepsis and maintain that drainage through the judicious use of setons
- for abscesses and fistulae that have an intra abdominal source the use of barium and CT studies should show a track
Peak incidence of ulcerative colitis?
aged 15-25 years and in those aged 55-65 years. It is less common in smokers.
Features of ulcerative colitis?
bloody diarrhoea
urgency
tenesmus
abdominal pain, particularly in the left lower quadrant
extra-intestinal features (see below)
Extra intestinal features of IBD?
Related to disease activity:
Arthritis: pauciarticular, asymmetric
Erythema nodosum
Episcleritis
Osteoporosis
Unrelated to disease activity:
Arthritis: polyarticular, symmetric
Uveitis
Pyoderma gangrenosum
Clubbing
Primary sclerosing cholangitis
Which extra intestinal features are more common to UC and which are more common to CD?
Arthritis is the most common extra-intestinal feature in both CD and UC
More common in crohns:
Episcleritis
More common in UC:
PSC
Uveitis
Pathology of ulcerative colitis?
Red, raw mucosa, bleeds easily
No inflammation beyond submucosa (unless fulminant disease)
Widespread superficial ulceration with preservation of adjacent mucosa which has the appearance of polyps (‘pseudopolyps’)
Inflammatory cell infiltrate in lamina propria
Neutrophils migrate through the walls of glands to form crypt abscesses
Depletion of goblet cells and mucin from gland epithelium
Granulomas are infrequent
What is seen in barium enema with ulcerative colitis?
Loss of haustrations
Superficial ulceration, ‘pseudopolyps’
Long standing disease: colon is narrow and short -‘drainpipe colon’
What is seen on endoscopy with ulcerative colitis?
Superficial inflammation of the colonic and rectal mucosa
Continuous disease from rectum proximally
Superficial ulceration, mucosal islands, loss of vascular definition and continuous ulceration pattern.
Management of ulcerative colitis?
-increased risk of development of malignancy
-Acute exacerbations are generally managed with steroids, in chronic patients agents such as azathioprine and infliximab may be used
Individuals with medically unresponsive disease usually require surgery- in the acute phase a sub total colectomy and end ileostomy. In the longer term a proctectomy will be required. An ileoanal pouch is an option for selected patients
Usual site of diverticular disease?
Taenia coli where vessels pierce the muscle to supply the mucosa
Symptoms of diverticular disease?
Altered bowel habit
Bleeding
Abdominal pain
Complications of diverticular disease?
Diverticulitis
Haemorrhage
Development of fistula
Perforation and faecal peritonitis
Perforation and development of abscess
Development of diverticular phlegmon
Diagnostic work up of diverticular disease?
Patients presenting in clinic will typically undergo either a colonoscopy, CT cologram or barium enema as part of their diagnostic work up.
Plain abdominal films and an erect chest x-ray will identify perforation. An abdominal CT scan (not a CT cologram) with oral and intravenous contrast will help to identify whether acute inflammation is present
Treatment of diverticular disease?
Increase dietary fibre intake
Mild attacks of diverticulitis may be managed conservatively with antibiotics.
Peri colonic abscesses should be drained either surgically or radiologically.
Recurrent episodes of acute diverticulitis requiring hospitalisation are a relative indication for a segmental resection.
Hinchey IV perforations (generalised faecal peritonitis) will require a resection (And stoma)
Severity classification for diverticular disease?
Hinchey classification
Hinchey I: Para-colonic abscess
Hinchey II: Pelvic abscess
Hinchey III: Purulent peritonitis
Hinchey IV: Faecal peritonitis
What is the commonest site in the abdomen for fluid to collect following a perforated appendix?
Pelvis
Examination signs in appendicitis?
Generalised peritonitis if perforation has occurred or localised peritonism.
Retrocaecal appendicitis may have relatively few signs.
Digital rectal examination may reveal boggy sensation if pelvic abscess
Diagnosis of appendicitis?
Raised inflammatory markers in the context of compatible history
Urine analysis: mild leucocytosis but no nitrites
Ultrasound may be useful in female patients
-Treatment of appendicitis?
-Appendicectomy which can be performed via either an open or laparoscopic approach.
Administration of metronidazole reduces wound infection rates.
Patients with perforated appendicitis require copious abdominal lavage.
Patients without peritonitis who —have an appendix mass should receive broad spectrum antibiotics and consideration given to performing an interval appendicectomy.
Be wary in the older patients who may have either an underlying caecal malignancy or perforated sigmoid diverticular disease.
Treatment of appendicitis?
-Appendicectomy which can be performed via either an open or laparoscopic approach.
-Administration of metronidazole reduces wound infection rates.
Patients with perforated appendicitis require copious abdominal lavage.
Patients without peritonitis who have an appendix mass should receive broad spectrum antibiotics and consideration given to performing an interval appendicectomy.
Be wary in the older patients who may have either an underlying caecal malignancy or perforated sigmoid diverticular disease.
At what position do most anal fissures present?
painful mucocutaneous defect in the posterior midline (90% cases)
Only a minority of patients with fissure in ano will have an anteriorly sited fissure. They are particularly rare in males
Earliest complication following reconstruction of an ileostomy?
Necrosis
(Dermatitis is most common)
What is normal ileostomy output?
roughly in the range of 5-10ml/Kg/ 24 hours
How can polyps be categorised?
neoplastic polyps
adenomatous polyps
non neoplastic polyps
What is ogilvie’s syndrome?
Colonic pseudo obstruction caused by dilatationl
Electrolyte imbalances/previous surgery RF and often seen
Risk of malignancy in association with polyps?
related to size, and is the order of 10% in a 1cm adenoma
High risk findings on colonoscopy for malignancy?
More than 2 premalignant polyps including 1 or more advanced colorectal polyps
OR
More than 5 pre malignant polyps
When should segmental resection or complete colectomy for polyps be considered?
- Incomplete excision of malignant polyp
- Malignant sessile polyp
- Malignant pedunculated polyp with submucosal invasion
- Polyps with poorly differentiated carcinoma
- Familial polyposis coli
-Screening from teenager up to 40 years by 2 yearly sigmoidoscopy/colonoscopy
-Panproctocolectomy and Ileostomy or Restorative Panproctocolectomy.
Rectal polypoidal lesions may be amenable to trans anal endoscopic microsurgery.
What should failed colonoscopy be managed with?
CT colonography in the first instance (more accurate than barium studies)
Extra intestinal manifestations of IBD?
Extraintestinal manifestation of inflammatory bowel disease: A PIE SAC
Aphthous ulcers
Pyoderma gangrenosum
Iritis
Erythema nodosum
Sclerosing cholangitis
Arthritis
Clubbing
What is proctalgia fugax?
Proctalgia fugax is a functional anorectal disorder characterized by severe, intermittent episodes of rectal pain that are self-limited.
Common location of haemorrhoids?
Location: 3, 7, 11 o’clock position
Causes of proctitis?
Causes: Crohn’s, ulcerative colitis, Clostridium difficile
Causes of ano rectal abscess?
E.coli, staph aureus
Positions: Perianal, Ischiorectal, Pelvirectal, Intersphincteric
In the lower GI system which is the major site of occult blood loss?
Right colon
What are anal fissures associated with?
Sexually transmitted diseases (syphilis, HIV)
Inflammatory bowel disease (Crohn’s up to 50%)
Leukaemia (25% of patients)
Tuberculosis
Previous anal surgery
Which polyp type has the highest risk of malignant transformation?
Villous adenoma
Examples of bulk forming laxatives?
Bran
Psyllium
Methylcellulose
Examples of osmotic laxatives?
Magnesium sulphate
Magnesium citrate
Sodium phosphate
Sodium sulphate
Potassium sodium tatrate
Polyethylene glycol
Docusate
Examples of stimulant laxatives?
Bisacodyl
Sodium picosulphate
Senna
Ricinoleic acid
When is chemotherapy for colonic cancer offered?
When patients have nodal disease
what is one of the commonest causes of colovesical fistula?
Diverticular disease
