Crohn's disease Flashcards
Name the two types of inflammatory bowel disease (IBD)
Crohn’s disease
Ulcerative colitis
Describe the age of presentation of crohn’s disease
Bimodal peak
15-30yo and 60-80yo
What type of course does inflammatory bowel disease follow?
Relapsing-remitting
What part of the GI system does crohn’s disease affect?
Any part
Most commonly targets the distal ileum or proximal colon
What is crohn’s disease characterised by?
Transmural inflammation - affecting all layers of the bowel
Deep ulcers and fissures - cobblestone appearance
Skip lesions - the inflammation is not continuous
Fistula formation
Give the microscopic appearance of crohn’s disease
Non-caseating granulomatous inflammation
Describe fistula formation in crohn’s’ disease
Between affected bowel and adjacent structures
Peri-anal 54% Entero-enteric 24% Recto-vaginal 9% Entero-cutaneous Entero-vesicalar
List the risk factors of crohn’s disease
Family history - 20% have 1st degree relative
Smoking - increases risk and relapse
White European descent (Ashkenazi jews)
Appendicectomy - risk increased directly after surgery
Give the symptoms of crohn’s disease
Episodic colicky abdo pain
Diarrhoea - chronic, may be mixed with blood or mucus
Systemic symptoms - malaise, anorexia, low-grade fever
Malabsorption and malnourishment
Oral aphthous ulcers - painful and recurring
Perianal disease
Describe the abdominal findings of crohn’s disease
Abdominal tenderness
Mouth or perianal lesions
Signs of malabsoprtion or dehydration
Extra-intestinal features
List the extra-intestinal features of crohn’s disease
MSK - enteropathic arthritis, metabolic bone disease, nail clubbing
Skin - erythema nodosum, pyoderma gangrenosum
Eyes - episcleritis, anterior uveitis, iritis
Hepatobiliary - primary sclerosing cholangitis, gallstones and cholangiocarcinoma
Renal - renal stones
Which bones joint does enteropathic arthritis commonly affect?
Sacroiliac
Describe erythema nodosum
Tender red/purple sc nodules typically on shins
Describe pyoderma gangrenosum
Erythematous papules/pustules that develop into deep ulcers
Occur anywhere - typically the shins
List the investigations done for crohn’s disease
Bloods - FBC, CRP - anaemia, low albumin (malabsorption), evidence of inflammation
AXR/CT - obstruction
Faecal calprotectin - inflammation
Stool sample - infection
Colonoscopy with biopsy
CT scan abdomen pelvis - bowel obstruction, perforation, collection or fistulae
MRI - enteric fistulae and perianal disease
Examination under anaesthesia with proctosigmoidoscopy - examine and treat perianal fistulae
Which drugs should be avoided in acute attacks of crohn’s disease
Anti-motility (loperamide)
How do you induce remission in crohn’s
Fluid resuscitation
Nutritional support
Prophylactic heparin
Anti-embolic stockings
Corticosteroid therapy
Immunosuppressive agents - mesalazine and azathioprine
Biological agents - infliximab can be trialled as a rescue therapy
How is crohn’s remission maintained?
Azathioprine
Mesalazine or methotrexate as alternatives can be trialled or added in
Biologics - infliximab, adalimumab, rituximab - rescue therapy during acute flares in those who have not responded to first line remission
Smoking cessation is advised
Colonoscopy surveillance - increased risk of colorectal malignancy
Enteral nutritional support
Antibiotics - concurrent infection or perianal disease - ciprofloxacin or metronidazole
Describe the surgical management of crohn’s disease
Ileocecal resection Peri-anal disease Stricturoplasty Small or large bowel resection Pre-operative optimisation and bowel sparing approach
List the complications of crohn’s disease
GI - Fistula, stricture formation, recurrent perianal abscess/fistulae, GI malignancy
Extra-intestinal - malabsorption, osteoporosis, increased risk of gallstones and renal stones
Describe the increased risk of renal stones in crohn’s disease
Due to malabsorption of fats in the small bowel which cause calcium to remain in the lumen, oxalate is then absorbed freely resulting in hyperoxaluria and formation of oxalate stones in the renal tract
Which investigation should be avoided in an acute flare of crohn’s
Coloscopy
Which is the most common IBD?
Ulcerative colitis
Which population is ulcerative colitis most prevalent among?
Caucasian
Give the age of presentation of ulcerative colitis
15-25yo
55-65yo
Bimodal
Describe the histological appearance of bowel in ulcerative colitis
Non-granulomatous inflammation with crypt abscess formation
Reduced goblet cells
What is the aetiology of ulcerative colitis
Genetics + environment
Describe the characterisation of ulcerative colitis
Diffuse continual mucosal inflammation of the large bowel
Which parts of the large bowel are affected in ulcerative colitis
Begins in the rectum and spreads proximally potentially affecting the entire large bowel
Distal ileum - backwash ileitis (incompetent ileocecal valve)
What is a protective factor in UC?
Smoking
Describe the clinical features of ulcerative colitis
Bloody diarrhoea Proctitis PR bleeding, mucus discharge, increased frequency, urgency and tenesmus Malaise Anorexia Low grade pyrexia
Which grading criteria is used to grade the severity of an exacerbation?
Truelove and Witt
Which criteria are included in the True love and Witt grading system?
Bowel movement number per day Blood in stool Pyrexia Pulse >90 Anaemia ESR
List the extra-intestinal manifestations of ulcerative colitis
MSK - enteropathic arthritis and nail clubbing
Skin - erythema nodosum
Eyes - episcleritis, anterior uveitis or iritis
Hepatobiliary - primary sclerosing cholangitis
What is primary sclerosing cholangitis?
Chronic inflammation and fibrosis of the bile ducts
What are the differentials for ulcerative colitis?
Crohn's Chronic infection - TB, schistosomiasis, giardiasis Mesenteric ischaemia Radiation colitis Malignancy IBS Coeliac
What investigations should be ordered when suspecting UC?
Bloods - FBC, U&Es, LFT, clotting, CRP - anaemia, low albumin, inflammation
Faecal calprotectin - inflammation
Stool sample - infection
Colonoscopy with biopsy
Flexible sigmoidoscopy
AXR - mural thickening and thumbprinting. In chronic cases then lead pipe colon
CT - toxic megacolon and bowel perforation
What is seen on colonoscopy in UC?
Continuous inflammation - ulcers and pseudo polyps
How is remission induced in ulcerative colitis
Fluid resuscitation Nutritional support Prophylactic heparin Corticosteroid therapy and immunosuppressive agents (mesalazine and azathioprine) Step wise approach
Describe the stepwise approach for inducing remission in ulcerative colitis
Mild/moderate - topical mesalazine or sulfasalazine - add oral prednisolone and oral tacrolimus. Higher doses for more extensive inflammation
Severe (all spread of disease) - IV corticosteroids and assess need for surgery. Add infliximab if no short term response
How is remission maintained in ulcerative colitis
Immunomodulators - mesalazine and sulfasalazine
Infliximab
Colonoscopy surveillance for colorectal malignancy
Enteral nutritional support
What percentage of UC patients require surgery?
30%
List the indications for acute surgical treatment of UC?
Disease refractory to medical management, toxic megacolon or bowel perforation
Reduce risk of colonic carcinoma if dysplastic cells are seen on routine monitoring
Which surgical procedure is curative in UC?
Total proctocolectomy - patient requires ileostomy
Which surgical procedure is used for symptom control in UC?
Sub-total colectomy with preservation of the rectum
List the complications of UC
Toxic megacolon
Colorectal carcinoma
Osteoporosis
Pouchitis
Describe the symptoms of toxic megacolon
Severe abdominal pain
Abdominal distension
Pyrexia
Systemic toxicity
What is the treatment of toxic megacolon
Decompression of the bowel or surgery
What is the risk of toxic megacolon
Risk of perforation
What is Pouchitis?
Inflammation of the ileal pouch with typical symptoms
What are the symptoms of Pouchitis?
Abdominal pain
Bloody diarrhoea
Nausea
How should Pouchitis be treated?
Metronidazole
Ciprofloxacin
What is the mechanism of action of infliximab?
TNF alpha inhibitor
