142 - IBD Inflammatory Bowel Disease Flashcards
What 2 diseases make up IBD?
Ulcerative Colitis
Crohn’s disease
What age of onset is common in IBD?
Peak in childhood and another peak in 60s
What are the symptoms of IBD?
Diarrhoea Blood + mucous in stooles Lower abdo pain/cramping Dyspeptic symptoms (crohn’s)
What is an important pointer towards IBD in terms of someone’s diarrhoea?
Nocturnal diarrhoea - waking from sleep.
What is the difference between the distribution of crohn’s and UC?
UC is only in the colon, always starting in the rectum and travlling up Crohn’s can be spread throughout the GI tract, with skip lesions between.
What different distributions of UC are there?
Proctitis - just in rectum Left sided colitis - travels up descending colon Pan colitis - extensive, most of colon
What is toxic megacolon?
When inflammation gets into the muscularis muscosa, which loses its integrity and expands - perforation.
What common intra-intestinal complications are there in Crohn’s?
Stenosis Fistulas Peri-anal disease
What diet helps Crohn’s patients?
An elemental diet - broken down into its smallest constituent parts already
What effect does smoking have on IBD?
Crohn’s - makes it worse, 2x more likely to get it UC - Protective - 40% lower risk of developing it
What risk factors are there for IBD?
Smoking (crohn’s) Family history (doesn’t matter if Crohn’s or UC) Infections?
What extraintestinal features are there of IBD ? (6 general, 2 crohn’s)
Fevers Weight loss Arthralgia Skin lesions Eye inflammation (episcleritis, uveitis) Hepatobilary disease Crohn’s = oral aphthous ulcers, orofacial granulomatosis
What investigations can you do on suspected IBD?
Haematology - micro/macro anaemia, leucocytosis, thombocytosis, CRP, ESR Biochemistry - low albumin, liver enzymes Stool examination - bacteria, toxins, calprotectin Colonoscopy - establish if inflamed, biopsies Radiology - Barium studies, CT
What kind of imflammation is seen in Crohn’s?
Granulomatous inflammation
Which out of Crohn’s or UC affects just the mucosa and which is transmural?
Crohn’s - transmural Uc - muscosa
What do Crohn’s ulcers look like macroscopicaly?
Cobble stones - longitudinal linear ulcers
Which disease of IBD causes crypt distortion?
UC Focal cryptitis possible in Crohn’s
Describe the ulceration in UC
Mucosal islands are formed around the ulcers that look like polyps
What is tenesmus? Which condition of IBD is it most seen in?
The feeling of needing to go to the bathroom to poo - never feel empty Seen in UC
Is there an increased risk of cancer in UC?
Yes, 20-30% increased risk of colorectal cancer Often part of surveillance program
List 7 differences between Crohn’s and UC
What malabsorbative effects can Crohn’s have for the patient?
B12 malabsorption
Bile salt malabsorption (leadinf to gall stones and wartery diarrhoea)
Fat malabsorption (steatorrhoea)
Obstructed lymphatics
What is the difference in aims of surgery in UC and Crohn’s?
UC - surgery is curative
Crohn’s surgery is just to alliviate complications
What opperation types are done in UC?
If urgent (due to failed medical management, toxic dilatation, perforation or blood) then they do a subtotal colectomy
Then electively they do:
Proctocolectomy + permenent ileostomy
Ileo-anal pouches ( joing SI up with anal canal, making a pouch to store stoole in)
What are the 3 main theories of pathogeneis of IBD?
Autoimmune
Dysfunctional immune response agains commensal bacteria
Infection with pathogenic organisms
What is the chromosomal locus that is related to IBD?
NOD2/CARD15
What is the aim of drug treatment in IBD?
Induce remission
Maintain remission
Prevent secondary effects
What drug regime would you use in Active UC?
1st: Mesalazine, then add in a corticosteroid
2nd: ciclosporin or inliximab
3rd: colectomy
What drugs would you use yo maintain remission of UC?
Mesalazine
If needed add Azathioprine
What drugs would you use for active Crohn’s?
!st: Corticosteroids
2nd: Azathrioprine or monoclonal antibodies (infliximab, Adalimubab)
What are the 2 main ASAs (aminisalicylates)
How do they work?
Sulfasalazine (1st on market)
Mesalazine (current 1st line)
Topical antiinflammatories
Inhibit synthesis of inflam mediators
Scavengers of O2 free radicals
How do corticosteroids act in IBD? What examples are there?
Potent anti-inflammatory agents
Inactivate pro-inflammatory factors
Eg. Hydrocortisone IV
Oral Prednisolone
What is a side effect of long term corticosteroids? What can be given to combat this?
Osteroperosis - give Bisphosphonates, Ca and Vit D
Cushing’s like side effects - mood face, central adiposity
What Immunosuppresant therapies are used in IBD?
Thiopurines (Azathioprine)
Cyclosporin
Methotrexate
Is cyclosporin used in UC or Crohn’s?
UC only
Is methotrexate used in UC or Crohn’s?
Crohn’s only
What must you do when prescribing methotrexate?
Must prescribe and dose weekly - crossing out any unwanted days .
Toxicity common - report all early signs
What is biological therapy for IBD?
The furture of medicine
Targets specific inflammatory and immuno pathways
What are the 2 drugs currently used in biological therapy of IBD?
Infliximab
Adalimumab
How does Infliximab work?
Targets membrane bound TNFalpha
Kills host cell
Has anti inflammatory function
How is adalimimab different to infliximab?
Infliximab is a chimeric antibody, however adalimumab is humanased - so has less side effects
What is Meckel’s Diverticulum?
An embryonic reminent
2% of population, 2 ft from ileocoecal valve, 2 inches long
Lined with villous mucosa
What is hirshsrung’s disease?
When there is an absense of ganglion cells in the neural plexus of some parts of the colon (they usually migrate from neural crest)
Present with a dilated megacolon - the thin section is the section that is abnormal, as can’t do proper peristalsis
Why wouldn’t you give NSAIDs as an antiinflammatory in IBD?
You want to minimise gut irritation
