IBD + IBS Flashcards
IBD definition
crohns disease and ulcerative colitis
both chronic, inflammatory, non infectious relapsing-remitting diseases in GI tract
IBD presentation
persistent diarrhoea (4-6 weeks) +/- blood +/- mucus
(blood and mucus are more common in UC)
tenesmus (present in crohns colitis or ulcerative colitis)
nocturnal fecal incontinence
lower abdominal pain + tenderness
fatigue + weight loss (cachexia) –> due to malasbsorption
digital clubbing
both have similar presentations especially if crohns affects the colon
(remember to think about malignancy with these symptoms as well)
what are the investigations in suspected UC
what are the expected results
bloods:
FBC –> anaemia + raised WCC (often IDA but remember anaemia of chronic disease)
ESR + CRP –> raised due to inflammation
LFTs —> hypoalbuminaemia due to malabsorption
Stool tests:
faecal calprotectin —> elevated due to bowel inflammation
infective pathogens MC+S —> important to exclude infection, -ve E.coli, salmonella, campylobacter
Flexi sig but if results are unclear then full colonoscopy, + biopsy:
Macroscopic –> continuous inflammmation, pseudopolyps + ulcers
Microscopic –> non-granulomatous, reduced goblet cells + crypt abscesses
if acute abdomen —> CT and abdominal AXR to check for life threatening complications of UC e.g. toxic megacolon or bowel perforation
What is the definition of UC?
Continuous and uniform inflammation of the large bowel (originating from the rectum)
commonly only affects the rectum –> proctitis
Where does UC affect?
Rectum - extending proximally
colon only
what risk factors are associated with UC
HLA-B27 gene
(also associated with Ankylosing spondylitis)
what are the UC specific features
affects only large colon –> continuous inflammation which extends proximally from rectum
only mucosa + sub mucosa of intestinal wall are inflamed
often only affects rectum –> proctitis
Macroscopic –> continuous inflammmation, pseudopolyps + ulcers
Microscopic –> non-granulomatous, reduced goblet cells + crypt abscesses
well between bouts of attack
how is UC classified
into mild, moderate and severe as per truelove + witts criteria (should say >6 not 76)
also according to area of colon affected:
Proctitis: rectum
Proctosigmoiditis: rectum and sigmoid colon
Left-sided colitis: rectum, sigmoid colon and descending colon
Extensive colitis: rectum, sigmoid colon, descending colon and transverse colon
Pancolitis: rectum and entire colon
management of UC
need to induce + maintain remission
topical = rectal
escalate in stepwise fashion if treatment not inducing remission
1st line –> aminosalicylates = mesalazine (topical) then sulfasalazine (oral) (to induce + maintain remission)
if remission still not achieved then add steroids e.g. prednisolone
corticosteroids are used when aminosalicylates aren’t working but you don’t use them long term to maintain remission, once it is induced you taper off steroid use due to side effects e.g. osteoporosis
calcineurin inhibitors can be added to steroids if they not sufficient e.g. ciclosporin
after severe relapse or if >=2 exacerbation in a year:
oral azathiopurine or oral mercaptopurine (need TPMT activity chekced beforehand)
when UC is refractory to other treatments –> biologics e.g. infliximab
surgery if patient cannot be managed by medical therapy or if they have severe complications e.g. toxic megacolon, bowel perforation
(methotexate not used in UC management)
What is administered to induce remission in a severe acute exacerbation of UC?
Intravenous corticosteroids
what are the complications of ulcerative colitis
increased risk of colorectal cancer –> colonscopy surveillance ffered depending on individual patient risk
osteoporosis
bowel perforation
increased blood clot risk
toxic megacolon
severe bleeding
what are key features seen in imaging of UC
lead pipe appearance of colon –> due to loss of haustral markings –> appears smooth walled + cyclindrical
seen on barium enema (x ray), CT, MRI
Per the Truelove and Witt’s criteria how many bowel motions is associated with severe UC?
6 or more loose and bloody bowel motions a day with fever, tachycardia, haemoglobin level of <105 g/L (<10.5 g/dL), and ESR of at least 30 mm/hour.
what are the extra intestinal manifestations of IBD
A PIE SAC
Apthous ulcers (CD>UC)
Pyoderma gangrenosum
I (eye) - iritis, uveitis, episcleritis
Erthema nodosum
Sclerosing cholangitis (primary) (UC>CD)
Arthritis (CD>UC)
Clubbing (CD>UC)
some are more common in each disease, but extraintestinal manifestations are more common in colonic disease
not all are correlated with severity of disease
how can IBD affect eyes
iritis, uveitis, episcleritis
(red eyes)
how can IBD affect skin
erythema nodosum - tender red nodules typically on shin
pyoderma gangrenosum - large rapidly developing painful ulcers
pallor from anaemia
erythema + pyoderma are more common in crohns
IBD complication associated with cholestasis
primary sclerosing cholangitis
inflammation of bile ducts –> scarring –> blockage
more common in UC
can be asymptomatic or can be quite debilitating e.g. jaundice + itching
raised ALP
What is Crohn’s disease?
Transmural inflammation of the GI tract affecting any part of the mouth to anus
forms skip lesions
investigations in suspected crohns disease
bloods:
FBC –> anaemia + raised WCC (often IDA but remember anaemia of chronic disease)
ESR + CRP –> raised due to inflammation
LFTs —> hypoalbuminaemia due to malabsorption
low B12 + vitamin D due to malabsorption
Stool tests:
faecal calprotectin —> elevated due to bowel inflammation
infective pathogens MC+S —> important to exclude infection, -ve E.coli, salmonella, campylobacter
colonoscopy + biopsy:
Macroscopic –> skip lesions + cobblestone appearance
microscopic –> non-caseating granulomas, goblet cells present in healthy tissue, transmural inflammaiton
if patient is systemically unwell e.g. hypotension, fever, teachycardia –> urgent hospital admission
Where does Crohn’s disease most commonly affect?
Terminal ileum and perianal areas
What type of inflammation is associated with Crohn’s disease?
Non-caseating granuloma formation
Describe the epidemiology of Crohn’s disease
Ashkenazi Jews
Bimodal peak at ages:
15-40
60-80
Describe the abdominal pain in Crohn’s disease
Crampy or constant right lower quadrant and periumbilical pain (terminal ileum is commonly affected)
what are signs seen on imaging in crohns disease
CT:
bowel wall thickening
affected bowel loops separated by focal/regionally increased fat (creeping fat)
comb sign - enlarged vasa recta
(MRI can be done too + less radiation)
CT with barium contrast:
- rosethorn ulcers - Deep ulcerations due to transmural inflammation
- string sign of Kantor (narrow terminal ileum filled iwth contrast looks like string because the wall has thickened so much)
- fistulas
What is the investigation of choice for suspected perianal fistulae in Crohn’s?
MRI pelvis
What is the confirmative test for Crohn’s disease?
Colonoscopy and biopsy (Histological evidence)
What is seen on endoscopy in Crohn’s?
Ulcers
Cobblestone appearance
Skip lesions
note: different types of endoscopy depending on which part of GI tract is affected, can be ileocolonscopy if lower GI symptoms and upper endoscopy for more upper GI symptoms e.g. dyspepsia nausea)
What medication is used to induce remission in Crohn’s disease?
1st line –> glucocorticoids - oral, topical or IV - e.g. prednisolone or hydrocortisone
(but not used long term)
2nd line –> Aminosalicyclates - mesalazine or sulfalazine - used when steroids are not tolerated or contra indicated but is not as effective as immunosuppressants)
Immunosuppressants (thiopurines) - Aziathioprine or mercaptopurine - can be add on therapy to steroids if there are still >=2 exacerbations in a year or the steroids can’t be tapered
If thiopurines not tolerated, methotrexate is add on instead
In children enteral nutrion can be an alternative to steroids as they suppress growth
If remission still not induced by any of the above —> biologics - infliximab or adalimumab
what is essential to do before starting thiopurines
aziathioprine or mercaptopurine
blood test to check for thiopurine methyltransferase (TPMT) activity
What is the maintenance therapy for Crohn’s disease?
1st line –> thiopurines (immunosuppresants) - Azathioprine or Mercaptopurine
2nd line –> (if thiopurines not tolerated) Methotrexate
also smoking cessation (note smoking makes crohns worse but might actually help UC)
how are peri-anal fistulae in crohns managed
oral metronidazole
infliximab - to close fistulae
drainage seton - to prevent premature closing of fistula which can lead to asbcess formation
(if abscess forms it needs to be surgically drained + IV antibiotics e.g. metronidazole + ceftriaxone)
What are the biological therapies administered for Crohn’s?
Adalimumab
Infliximab
what are the complications of crohns disease
peri anal fistulas and abscesses
obstruction
stricture –> then there is bowel dilatation proximal to stricture
perforation
colorectal cancer (risk is lower than in UC though)
small bower cancer
osteoporosis
What are the indications for surgical management in Crohn’s?
surgery is not generally curative, but very common in CD patietns
occurs due to severe refractory disease or due to complications –> strictures, obstructions, fistulas
What is the definition of IBS?
Chronic condition characterised by recurrent abdominal pain associated with bowel dysfunction
it is a diagnosis of exlcusion
What is the epidemiology of IBS?
Females > M (2:1)
<50 Years.
What is the presentation of IBS?
consider IBS in patients who have had the following for at least 6 months:
Abdominal pain, and/or
Bloating, and/or
Change in bowel habit
patients often are lethargic, back pain, nausea too
red flag symptoms which mean its probably not IBS (merit further investigation e.g. colonoscopy):
rectal bleeding
unexplained/unintentional weight loss
family history of bowel or ovarian cancer
onset after 60 years of age
how is IBS diagnosed
**primimary care: **
if abdominal pain has been present for at least 6 months
and relieved by defecation or associated with altered bowel frequency (increased or decrerased) or altered stool form (hard, lumpy, loose watery), in addition to 2 of the following 4 symptoms:
altered stool passage (straining, urgency, incomplete evacuation)
abdominal bloating (more common in women than men), distension, tension or hardness
symptoms made worse by eating
passage of mucus
**secondary care: **
Rome IV criteria –> Recurrent abdominal pain, on average, at least 1 day per week in the last 3 months (with symptom onset at least 6 months prior to diagnosis) which is associated wih at least 2:
Related to defaecation
Change in frequency of stool
Change in stool form.
what are the investigations in suspected IBS
need to rule out other more serious causes for symptoms:
FBC - patient shouldn’t be anaemic or have raised platelets
CRP + ESR - markers of inflammation which shouldn’t be raised
Coeliac serology - should be -ve
FIT test - should be -ve
faecal calprotectin - marker of gut inflammation which should be -ve
following tests are NOT required: abdominal ultrasound, sigmoidoscopy/colonoscopy, thyroid function tests, feacal occult blood test, faecal ova and parasite test, hydrogen breath test
What lifestyle management is available for IBS?
if constipation - increase soluble fibre uptake, consider supplements
if diarrhoea/bloating - less insoluble fibre + less caffeine, alcohol, fizzy drinks, less fructose (fruit)
Which criteria is used in the diagnosis of IBS?
in secondary care
Rome IV criteria
IBD presentation
persistent diarrhoea (4-6 weeks) +/- blood +/- mucus
(blood and mucus are more common in UC)
tenesmus
nocturnal fecal incontinence
abdominal pain
both have similar presentations especially if crohns affects the colon
what diagnostic test helps distinguish between IBS and IBD
fecal calprotectin
marker of intestinal inflammation which is raised in IBD but not in IBS
what are the UC specific features
affects only large colon –> continuous inflammation which extends proximally from rectum
only mucosa + sub mucosa of wall are inflamed
often only affects rectum –> proctitis
Crohns specific presenation features
peri-anal disease –> skin tags, fistulas, scarring, abscesses or sinus
diarrhoea is not necessarily bloody unless it is crohns colitis
apthous ulcers
what are the complications of ulcerative colitis
increased risk of colorectal cancer –> colonscopy surveillance depending on individual patient risk
primary sclerosing cholangitis
osteoporosis
bowel perforation
increased blood clot risk
toxic megacolon
severe bleeding
how do you make a diagnosis of IBS
need to rule out other causes for symptoms
symptoms need to have been present for at least 6 months
what are the red flag features change in bowel habit
rectal bleeding
unexplained/unintentional weight loss
family history of bowel or ovarian cancer
onset after 60 years of age
would make you think IBS not likely
