Gastrointestinal Flashcards
Describe the differences between ulcerative colitis and Crohn’s disease.
Ulcerative colitis is diffuse inflammation while Crohn’s disease is patchy inflammation.
UC is superficial (mucosal); CD is transmural
UC affects rectum and extends proximally; CD may affect any part of the GIT
What are some histological features of ulcerative colitis?
- mucosal/submucosal inflammation
- lymphocytic infiltrate
- NO granulomas
- goblet cell depletion
- crypt distortion
- cryptitis
- crypt abscesses
What are some histological features of Crohn’s disease?
- transmural inflammation
- lymphocyte + macrophage infiltrate
- granulomas in 50% cases *** if you see granulomas, then CD, not UC
What is the possible aetiology of IBD?
- Abnormal immune response
- inappropriate activation of the immune system
- failure to downregulate immune system - Environmental triggers
- diet, medications, psychological stress
- smoking protects against UC
- appendicetomy protects against UC - Genetics
- possible susceptibility genes (NOD2/CARD15 for Crohn’s)
How may IBD present in patient?
Note: clinical presentation depends on location, extent and severity. GI symptoms: - abdominal cramps - diarrhoea - rectal bleeding - urgency - tenesmus Systemic symptoms: - weight loss - malaise - anorexia - fever - arthralgia Perianal involvement (20-25%) - abscesses - fistulae - fissures Extraintestinal manifestations
What are the extraintestinal manifestations of IBD?
Associated with active GI disease: - oral ulcers - erythema nodosum - large joint arthritis - episcleritis Independent of GI disease: - Primary Sclerosing Cholangitis (PSC) - ankylosing spondylitis - uveitis - pyoderma gangrenosum - kidney stones - gallstones
How do you differentiate IBD from IBS?
History: - systemic symptoms, e.g. weight loss - nocturnal symptoms - continuous (rather than intermittent) symptoms - extraintestinal manifestations - FHx of IBD Examination: - PR bleeding - extraintestinal manifestations - perianal involvement Investigations: - anaemia - iron or other nutrient deficiencies - raised inflammatory markers (CRP, ESR) - elevated faecal calprotectin
How do we diagnose IBD?
Colonoscopy confirms diagnosis
- it also determines the extent and severity of the disease
- can also provide therapeutic dilatation of strictures
- also surveillance for CRC
What are the distinguishing features of Crohn’s disease?
- Granulomas
- Asymmetrical involvement
- Focal lesions
- Strictures
- Skip lesions
- Fistulisation
- Small bowel involvement
- Rectal sparing
What are the goals of management for IBD?
Short term goal = induce remission - relieve symptoms and improve QOL Long term goal = maintain remission - control inflammation (w/o steroids) - prevent flares - prevent complications - reduce need for hospitalisation or surgery
What are the complications of ulcerative colitis?
Haemorrage Growth retardation Osteoporosis Thromboembolism Colorectal cancer *Toxic megacolon (*unique to UC)
What are the complications of Crohn’s disease?
Haemorrage Growth retardation Osteoporosis Thromboembolism Colorectal cancer *Strictures *Fistulae *Perforation *Abscess
What are the key functions of the liver?
- Synthesis of clotting factors
- Glucose homeostasis
- Albumin synthesis
- Conjugation and clearance of bilirubin
- NH3 metabolism
- Drug metabolism
- Immune
What is the definition of acute liver failure?
Rapid deterioration of liver function (within 30 days), specifically characterised by encephalopathy due to excess ammonia.
What are the causes of chronic liver disease?
The Big 3:
- HBV
- HCV
- Alcohol
Autoimmune 3
- Autoimmune hepatitis (AIH)
- Primary biliary cirrhosis (PBC)
- Primary slcerosing cholangitis (PSC)
Metabolic 3:
- Haemachromatosis
- Wilson’s disease
- Fatty liver disease (NASH)
Other 3:
- Budd-Chiari (hepatic vein thrombosis)
- Chronic biliary obstruction
- alpha 1-antitrypsin deficiency