Medicine - Gastroenterology Flashcards
How do you differentiate between gastric and duodenal ulcers?
After a meal
Gastric = Greater pain
Duodenal = Decrease pain (pain when hungry)
What is associated with the majority of peptic ulcers?
H. pylori
95% of duodenal ulcers
75% of gastric ulcers
Name 4 drugs associated with peptic ulcers
NSAIDs
SSRIs
corticosteroids
bisphosphonates
Which syndrome is associated with peptic ulcers? What is the pathophysiology?
Zollinger Ellison Syndrome
rare cause characterised by excessive levels of gastrin, usually from a gastrin secreting tumour
Which type of peptic ulcer is more common?
Duodenal
What is the first line investigation for peptic ulcer disease?
H. pylori urea breath test or stool antigen test
Mx of peptic ulcer disease
-ve H. pylori: PPIs
+ve H. pylori: eradication therapy- PPI + Amoxicillin BD + Clarithromycin/ Metronidazole BD
What is the only test that can be used to check for H. pylori eradication?
Urea breath test
What is the investigation for C. dificile infection?
C. difficile toxin (CDT) in stool
C. difficile antigen positivity only shows exposure to the bacteria, rather than current infection
Mx of first episode C. difficile infection
1st: Vancomycin PO for 10 days
2nd-line: Fidaxomicin PO
3rd-line: Vancomycin PO +/- Metronidazole IV
Mx of recurrent C. difficile infection
<12w of Sx resolution: Fidaxomicin PO
>12w of Sx resolution: Vancomycin OR Fidaxomicin PO
Mx of life-threatening C. difficile infection
Vancomycin PO + Metronidazole IV
specialist advice - surgery may be considered
Describe the distribution of UC
Starts at Rectum (hence most common site for UC)
Continuous.
Never spreads beyond ileocaecal valve
Differentiate mild, moderate and severe flares of ulcerative colitis
Mild: <4 stools per day, little blood
Moderate: 4-6 stools per day, varying blood
Severe: >6 stools per day, bloody diarrhoea, systemic upset
What is the name of the criteria used to stage IBD, and what are the 6 criteria?
Truelove + Witts: HR Temperature Bowel movements PR bleeding Haemoglobin ESR
Give 4 gastro symptoms UC presents with
bloody diarrhoea
urgency
tenesmus
abdo pain, esp. left lower quadrant
Which 6 extra-intestinal manifestations of UC are related to disease activity?
Erythema nodosum
Pauci-articular Arthritis
Apthous ulcers
Episcleritis
Osteoporosis
VTE risk
Which 4 extra-intestinal manifestations of UC are NOT related to disease activity?
Axial arthritis: sacroiliitis/ ankylosing spondylitis
Pyoderma gangrenosum
Uveitis
Primary sclerosing cholangitis
Give 3 triggers for a UC flare
Stress
Drugs: NSAIDs, Abx
Cessation of smoking
What is seen on barium enema in UC? (3)
loss of haustrations
superficial ulceration, ‘pseudopolyps’
long standing disease: colon is narrow + short -‘drainpipe colon’
Recall 2 histological findings of the gut layer for Crohn’s and UC
Crohn’s: Increased goblet cells, granulomas
UC: Decreased goblet cells, crypt abscesses
When should a diagnostic colonoscopy for UC be avoided? What investigation is preferred?
In severe colitis- risk of perforation
Do flexible sigmoidoscopy
What is the most common affected portion of the bowel in Crohn’s vs UC?
Crohn’s: terminal ileum (so RIF mass)
UC: rectum
Describe the typical features of inflammation in Crohn’s vs UC
Crohn’s: Skip lesions, rose-thorn ulcers, cobblestoning, string sign of kantor (narrow ileum stricture)
UC: ‘lead-pipe’, pseudo-polyps, thumbprinting
Which type of IBD carries the highest risk of colorectal cancer?
UC
In which form of IBD are fissures more common and why?
Crohn’s - because it affects the full thickness of the bowel wall
Differentiate the appearance of stool in active Crohn’s vs UC
Crohn’s: non-bloody diarrhoea
UC: bloody diarrhoea which may contain mucous
Which type of IBD is associated with gallstones and why?
Crohn’s
Bile acids are not properly absorbed as terminal ileum is affected
In which form of IBD can surgery be curative?
UC
Recall the possible extra-intestinal manifestations of IBD
A PIE SAC Aphthous ulcers Pyoderma gangrenosum (skin ulcers) I (eye) = uveitis, iritis, episcleritis Erythema nodosum Sclerosing cholangitis (UC Only) Arthritis Clubbing (Crohn's moreso)
Describe the process of inducing remission in Crohn’s
Steroids:
If mild: oral prednisolone
If severe: IV hydrocortisone
If no improvement after 5 days –> infliximab
Oral budesonide can be used in disease between the distal ileum and the ascending colon
Nutritional:
Replace diet with whole protein modular diet - excessively liquid, for 6-8 weeks - this helps to replace lost weight
Describe the process of maintaining remission in Crohn’s
First line: DMARDs (eg azothioprine)
Alternatives: infliximab/ aminosalicylates
Mx of acute severe UC
Admit
1st: IV Hydrocortisone or Methylprednisolone
2nd: anti-TNF (ciclosporin/ infliximab)
If severe intractable colitis: Colectomy
Induction of remission of moderate-severe UC
Prednisolone/ Budesonide PO
or
Infliximab/ Adalimumab
+/- Azathioprine
Induction of remission of mild-moderate UC
Proctitis: Mesalazine TOP (rectal)
Left sided: Mesalazine TOP + PO +/- Budesonide PO
Extensive: Mesalazine PO +/- Prednisolone/ Budesonide PO
Maintenance of remission in mild-moderate UC
Mesalazine TOP alone (daily or intermittent)
or
Mesalazine PO + TOP (daily or intermittent)
Maintenance of remission in mild left sided and extensive UC
Mesalazine PO
Maintenance of remission in moderate to severe UC / if >2 flare-ups in 1y
Thiopurine: Azathioprine or Mercaptopurine PO
or
Biologic: Infliximab IV or Adalimumab SC
What is the main side effect of aminosalicylates to remember?
Acute pancreatitis
What are the options for surgery in UC?
Emergency:
Hartmann’s protosigmoidectomy + end ileostomy –> later IPAA (ileal-pouch ana anastomosis)
Non-emergency:
Protocolectomy + IPAA or
Panprotocolectomy + end ileostomy
What are the criteria used to diagnose IBS?
It’s a diagnosis of excusion based on the ROME III criteria:
- Improvement with defaecation
- Change in stool frequency
- Change in stool form/ appearance/ consistency
Recall the grading of haemarrhoids
1st: in rectum after defaecation
2nd: prolapse at defaecation, spontaneous reduction
3rd: prolapse at defaecation, manual reduction
4th: persistently prolapsed
What is the first line management of haemorrhoids?
Increased fruit/ fibre
Stool softener
Topical analgesics
Topical steroids (suppository)
Recall some non-operative ways of managing haemorrhoids?
Rubber-band ligation
Sclerotherapy
Electrotherapy
Infrared coagulation
Recall 3 surgical options for managing haemorrhoids
Haemarrhoidectomy
Haemorrhoidopexy
HALO (haemorrhoidal artery ligation operation)
What is the standard treatment for C diff enterocolitis?
PO vancomycin
2nd line fidaxomicin
If severe/unresponsive –> IV vanc + met
Which bacteria demonstrates “tumble weed motility”?
Listeria monocytogenes
How can listeria gastroenteritis be treated?
Amoxicillin/ ampicillin
Which 3 antibiotics are most associated with causing C diff enterocolitis?
Cephalosporin
Clindamycin
Ciprofloxacin
Which gastroenteritis-causing pathogen is associated with undercooked seafood?
Vibrio parahaemolyticus
Which gastroenteritis-causing pathogen is associated with shellfish handlers?
Vibrio vulnificus (in immunocompetent usually causes cellulitis/ nec. fasciitis)
Recal the site of absorption of iron, folate and B12
Iron: Duodenum
Folate: Jejunum
B12: Ileum
Which skin condition is pathognomonic for coeliac disease?
Dermatitis herpetiformis
Describe the appearance of stool in coeliac disease
Waterey, grey, frothy
What system is used to grade coeliac disease?
Marsh system
Recall some typical histological findings in coeliac disease
Villous atrophy and crypt hyperplasia
Recall the name of the scoring system used to diagnose appendicitis and its components
Alvarado score:
Signs:
RLQ tenderness (+2)
Fever
Rebound tenderness
Symptoms:
Anorexia
Nausea/vomiting
Pain migration to RLQ
Lab:
Leucocytosis (WBC > 10,000) (+2)
Left shift (>75% neutrophils)
Recall some eponymous signs on examination that are indicative of appendicitis
Rovsing’s sign: Pain greater in RIF than LIF when LIF pressed
Cope’s sign: Pain on passive flexion and internal rotation of the hip
What does rebound tenderness indicate about appendicitis?
That it involves peritoneum
What sign can be used to demonstrate a retrocaecal appendix?
Pain on extending hip (Psoas sign)
How should an un-perforated appendix be managed?
Prophylactic antibiotics followed by laparoscopic appendectomy
How should a perforated appendix be managed?
Abdominal lavage
What is “Amirand’s triangle”?
Triad of conditions that predisposes to gallstone disease:
Low lecithin
Low bile salts
High cholesterol
How can the symptoms of cholecystitis and cholangitis be differentiated?
Cholecystitis = no jaundice Cholangitis = obstructive jaundice
How can the symptoms of cholecystitis and biliary colic be differentiated?
Biliary colic = RUQ pain
Cholecystitis = RUQ pain + fever
What is Charcot’s triad?
Triad of classical symptoms of ascending cholangitis
Jaundice
RUQ pain
fever
What is Reynauld’s pentad?
Pentad of classical symptoms of severe ascending cholangitis Jaundice RUQ pain Fever Hypotension Confusion
Within what time frame should a laparoscopic cholecystectomy be performed for cholecystitis?
1 week (use antibiotics whilst waiting)
What is “Mirizzi syndrome”?
Impaction of common hepatic duct by a GB stone
What is the pathophysiology of “porcelain gallbladder”?
Chronic cholecystitis can –> calcification of GB walls
Recall some complications of acute cholecystitis
Chronic diarrhoea (GB removal --> more bile reaches large intestine --> more water and salt draw into bowel) Vitamin ADEK malabsorption (can --> bleeding due to less 2,7,9,10 production)
What is a SeHCAT study?
Selenium in Homocholic Acid Taurine - assesses bile acid retention to see if this is cause of diarrhoea
How can diarrhoea post-cholecystectomy be managed?
Cholestyramine (binds to bile acids and makes the biologically inactive)
How can ascending cholangitis be managed?
IV antibiotics followed by therapeutic ERCP within 48 hours
What are the key symptoms of cholangiocarcinoma?
Palpable gallbladder, obstructive jaundice
What is the gold-standard investigation for staging cholangiocarcinoma?
ERCP
Recall and compare the symptoms of PBC vs PSC
PBC:
Pruritis, obstructive jaundice, RUQ pain in 10%, hyperholesterolaemia
PSC:
Pruritis, obstructive jaundice, steatorrhoea, splenomegaly
How can features of PBC be remembered?
The M rule:
IgM
anti-Mitochondrial antibodies, M2 subtype
Middle aged females
Recall and compare the antibodies involved in PBC vs PSC
PBC: AMA
PSC: p-ANCA
Recall and compare the best way to investigate PBC vs PSC
PBC: cholestatic liver biochemistry and AMA blood test (biopsy is diagnostic but often not carried out)
PSC: MRCP is preferred to start (rosary sign), then p-ANCA + BIOPSY (‘onion skin’ appearance of obliterated cholangitis)
Recall and compare the management approaches for PBS vs PSC
PBS: ursodeoxycholic acid + cholestyramine + prednisolone for associated autoimmune disease
PSC: observation –> liver transplant
What % of patients with PSC get cholangiocarcinoma?
10%