Gastroenterology: Ulcerative Colitis Flashcards
Define UC [1]
UC is a type of inflammatory bowel disease that characteristically involves the rectum and extends proximally to affect a variable length of the colon.
UC is a disease characterised by diffuse inflammation of the colonic mucosa and a relapsing, remitting course
UC usually involves only the mucosa
Describe the difference in effect of smoking between UC and Crohns [2]
Explain why this difference might occur [1]
Crohns:
- Smoking quickens disease progression
UC:
- Smoking is protective
Smoking inhibits macrophage functions; CD: can’t clear bacteria; but UC dampens immune response
Explain the pathophysiology of UC
Innappropriate immune response to colonic flora in genetically suseptible individuals
Causes haemorrhagic / hyperaemic colonic mucosa +/- pseudopolyps caused by inflammation
Punctate ulcers may extend deep into lamina propria
Submucosal inflammtion
Explain why increasing stress worsens IBD [2]
Stress increases inflammatory response; via gut-brain axis and enteric nervous system
Which drug class is detrimental for IBD? [1]
Explain your answer [2]
NSAIDs: create holes in stomach / small bowel: causes gut microbiota & immune system to react
What type of foods are bad for IBD? [3]
Why are these diet types bad? [1]
- High animal fat
- Low fibre intake
- Emulsifiers and thickeners
Alter gut microbiome
What is the difference in effect of exercise between UC & CD? [1]
:Regular active exercise reduces risks of developing Crohn’s (but not UC) & relapse of Crohn’s and possibly UC
What are general presenting complaints of IBD? [4]
Diarrhoea
Abdominal pain
Rectal bleeding
Fatigue
Weight loss
Systemic features in attack: fever, malaise, anorexia
Name three subtypes of UC [3]
Proctitis: Inflammation affecting the rectum only
Left-sided colitis: Inflammation affecting the rectum and the sigmoid and descending colon
Pancolitis: Inflammation affecting the whole colon, from the rectum to the ileo-caecal valve
What are the classic presenting complaints of UC? [6]
Diarrhoea - urgency
Blood in stools
Fatigue
Weight loss
Cancer
Extra-intestinal manifestations: ulcerations in mouth; uveititis; different types of arthritis; erythema nodosum typically in shins/feet and pyoderma gangrenosum; peri-anal disease
What is the hallmark symptom of UC? [1]
The hallmark of UC is bloody diarrhoea / rectal bleeding.
State 4 Signs of UC [4]
· Tender abdomen – LIF, but generally mild
· Pallor
· Tachycardia in acute attack
· Leukonychia due to hypoalbuminemia and poor nutrition
Describe blood investigations used for diagnosing UC [3]
Describe stool investigations used for diagnosing UC [2]
Describe imaging used for investigating UC? [2]
Bloods:
- IDA may be seen in those with moderate-severe attacks: microcytic anaemia
- Low ferritin; low albumin
- Raised inflammatory markers: CRP & ESR suggest inflammation
- Platelets
Stool test:
- Faecal calprotectin (an inflammatory marker expressed by immune cells in the lining of the gut wall which can be detected in the stool. This helps us to differ between IBS and IBD). Used prior to endoscopy)
- Stool MC&S: to exclude Campylobacter, C. diff, Salmonella, Shigella, E.colo
Imaging:
- Abdominal x-ray (looking for toxic megacolon)
- Endoscopy (colonoscopy)
In addition to IBD, other causes of a raised faecal calprotectin include? [4]
bowel malignancy
coeliac disease
infectious colitis
use of NSAIDs
What is is the investigation of choice for establishing the diagnosis of UC? [2]
What is is the investigation of choice for severe UC? [1]
Colonoscopy with multiple intestinal biopsies
severe colitis:colonoscopy should be avoided due to the risk of perforation - a flexible sigmoidoscopy is preferred
Abdominal X-rays are useful for looking at dilatation of the bowel and perforations. Dilatation is said to be present if:
Small bowel: diameter > [] cm
Large bowel: diameter > [] cm
Caecum: diameter > [] cm
Abdominal X-rays are useful for looking at dilatation of the bowel and perforations. Dilatation is said to be present if:
Small bowel: diameter > 3cm
Large bowel: diameter > 6cm
Caecum: diameter > 9cm
Descricbe characteristic findings of colonoscopy in UC patients [4]
- rectal involvement
- continuous uniform involvement
- loss of vascular marking
- diffuse erythema
- mucosal granularity
How can you differentiate between UC and CD via endoscopy? [6]
UC:
- continuous inflammation:
- there is no areas of normal mucosa in-between areas of inflammation
- diffuse erythema
- friability, granularity
- loss of vascular pattern in the colon.
CD:
- incontinuous areas of inflammation normal bowel in-between inflammatory segments
- deep fissuring ulcers
- “cobblestoned” mucosa are present.
How do UC & CD differ histoligically? [2]
UC: affects just the luminal epithelial layer of the bowel and does not extend through the entire layer of the wall
CD: affects all layers of the bowell
Describe how you differentiate between recent v chronic UC via a histology sample? [1]
Chronic:
- crypt architecture distortion: they look twisted and disorganised
Describe surgical managment of UC:
- Acute disease [1]
- Chronic disease [1]
Subtotal colectomy with end ileostomy and preservation of the rectum. For acute disease
Proctocolectomy: the surgical removal of the rectum and all or part of the colon, and is usually preceded by an ileostomy (standard procedure)
Name and describe an important complication of UC [1]
toxic mega colon (TMC): medical emergency, which refers to toxic, non-obstructive, dilatation of the colon (> 6cm):’
* Fever
* Tachycardia
* Hypotension
* Dehydration
* Altered mental status
* Biochemical abnormalities (e.g. leukocytosis, anaemia, and electrolyte derangements)
[] are the investigations of choice in primary sclerosing cholangitis.
What sign would indicate a positive result? [1]
ERCP/MRCP are the investigations of choice in primary sclerosing cholangitis
Multiple biliary strictures giving a ‘beaded’ appearance
State a key finding of UC under endoscopy [1]
Pseudopolyps: widespread ulceration with preservation of adjacent mucosa which has the appearance of polyps
Describe a structural change that occurs as a response to active inflammation in UC patients [3]
Crypt abscesses form as a response to active inflammation.
Crypt abscesses are the accumulation of inflammatory cells within crypts, which are tube-like glands found in the lining of the gastrointestinal system (i.e., digestive tract). The accumulation of inflammatory cells can cause damage to the surrounding cells, thereby preventing the gland from functioning properly and secreting various substances.
The abscesses are commonly neutrophilic in UC.
Sulphasalazine may be used to treat UC.
Name a haematological SE of this treatment [1] and describe how this may present on blood smear [1]
Sulphasalazine may cause haemolytic anaemia
this can present withHeinz bodies
Sulphasalazine Heinz body
Name a restorative option in UC [1]
Restorative options in UC include an ileoanal pouch. This procedure can only be performed whilst the rectum is in situ and cannot usually be undertaken as a delayed procedure following proctectomy.
