GI conditions: intestines Flashcards
Does UC or Crohn’s have a greater risk of developing colon cancer
UC
Differentiating between UC and Crohn’s via symptoms
UC: usually bloody diarrhoea
Crohn’s: usually non-bloody diarrhoea
Differentiating between UC and Crohn’s via histology
UC: superficial inflammation. Crypt abscesses.
Crohn’s: transmural inflammation. Granulomas
Differentiating between UC and Crohn’s via endoscopy
UC: affected from rectum to ileocaecal valve. Get pseudopolyps (widespread ulceration)
Crohn’s: affected anywhere from mouth to anus. Get cobblestone appearance (deep ulcers + skip lesions)
What causes crypt abscesses? What GI condition is associated with this
Crypt abscess = neutrophils migrating through the wall of glands
UC
What causes granulomas? What GI condition is associated with this
Collection of macrophages to ward off “foreign bodies” during inflammation
Crohn’s
AXR features of UC
- leadpipe colon (narrow short colon, loss of haustra)
- loss of haustra
- pseudopolyps
AXR features of Crohn’s
- Kantor’s string sign (bowel strictures)
2. Rose thorn ulcers (deep ulcers)
What causes thumbprinting on AXR
Wall thickening of colon, due to inflammation/ infection
–> colitis
What causes loss of haustra on AXR
- Chronic UC
2. Toxic megacolon
Features of mild flare up of UC
Diarrhoea <4 times
Features of moderate flare up of UC
Diarrhoea 4-6 times a day
No systemic features
Features of severe flare up of UC
Diarrhoea >6 times a day
Systemic features eg fever, tachycardia, raised CRP
Best cancer marker to monitor patients with colon cancer
CEA
What surgery is done for colon cancer in
caecum - proximal transverse colon distal transverse - descending colon sigmoid colon upper/middle rectum distal 1/3 of rectum
caecum - proximal transverse colon = R hemicolectomy
distal transverse - descending colon = L hemicolectomy
sigmoid colon = Hartmann’s (sigmoidectomy + end colostomy)
upper/middle rectum = anterior resection
distal 1/3 of rectum = abdominal-perineal excision of rectum
Describe grades 1-4 of internal haemarrhoids
- No prolapse, but promiment blood vessels
- Prolapse which can spontaneously reduce
- Prolapse which requires manual reduction
- Permanent prolapse
Chronic treatment for mild-moderate UC that only affects distal colon
Rectal sulfasalazine
Chronic treatment for mild-moderate UC that is widespread
Oral + rectal sulfasalazine
Chronic treatment for moderate-severe UC
- Oral + rectal sulfasalazine
- Biologics eg infliximab
- Azathioprine if >2 exacerbations a year/ severe relapse
Management of an acute flare of UC
- IV corticosteroids for 72h
- IV ciclosporin
- Infliximab
- Surgery
Indications for surgery in acute flare of UC
- Stools frequency >8/day
- Fever, tachycardia
- AXR: colon dilation
- low, albumin, low Hb, high platelets, high CRP
When would a UC patient be put on regular oral azathioprine/ mercaptopurine
- severe relapse of UC
- 2 or more exacerbations in a year
Management of mild-moderate flare of UC
Oral corticosteroids
First line investigation for acute mesenteric ischaemia
Lactate (would get lactic acidosis)
Most common site of diverticulitis
Sigmoid colon
What does a positive C Diff antigen mean
Exposure to bacteria (does not necessarily indicate current infection)
Most common cause of hereditary colon cancer
HNPCC (Lynch syndrome)
What drug may reduce the risk of colon cancer in those with HNPCC (Lynch syndrome)
Aspirin daily
HNPCC (Lynch syndrome)
-What cancers are associated with this
Colon cancer
Endometrial cancer
Pancreatic cancer
Gastric cancer
FAP
-What cancers are associated with this
Colon cancer
Breast cancer
Ovarian cancer
Gardner’s syndrome (osteomas of skull and mandible)
Difference in presentation between large and small bowel obstruction
Small bowel:
Present with vomiting early and absolute constipation late
Large bowel:
Present with constipation earlier
Inheritance of FAP
Autosomal dominant
2 most common watershed areas in colon
What arteries are involved?
Splenic flexure: SMA + IMA
Rectosigmoid junction: IMA + hypogastric artery
UC is associated with which HBP condition?
UC is associated with PSC
