IBD Flashcards
what is IBD?
irritable bowel disease
chronic recurring inflammation of the GI tract
what are examples of IBD
crohn’s disease
ulcerative colitis
Describe crohns disease
- inflammation of ANY part of the GI tract
- involves ileum, caecum, colon
- effects regions in a DISCONTINOUS pattern - skip lesions
what are the complications of CD
malignancy
anal lesions
abdominal mass
What is ulcerative colitis
- confine to the colon
- effects region in a CONTINOUS pattern
- starts in the rectum and progresses upwards
what are the complications of UC?
blood loss electrolyte disturbances blood in stool mucus sometimes pain
Does UC respond to antibiotics?
no but CD does
Is there a possibility for UC to reoccur after surgery?
no but CD does
Is fistulas present in UC or CD?
CD
What are symptoms of IBD
bloody diarrhoea urgency to empty bowels malnutrition fever weight loss
What is a ESR test? Describe the process.
measures severity of CD and UC
RBCs places in a tube sediment at a set rate, if inflamed they clump together and sediment faster
- indication of inflammation
What are extra intestinal manifestations as a result of IBD/treatment?
dermatological
rheumatological
ocular
general - kidneys and live
What are skin lesions and when are they most common?
erythema nodosum - tender red bumps
pyoderma gangrenosum - deep chronic ulcers - more common in UC
What happens to the bine due to IBD?
30-60% of Pt with IBD have lower bone density - osteoporosis/ ostroperia
- prolong use of steroids, inflammation and Vit B deficiency may contribute
spinal arthritis causing inflammation and fusing of vertebra - rare
describe ocular.
- commonly conjunctivitis, iritis, episderitis
what are the symptoms of ocular?
ocular pain
photophobia
blurred vision
headache
describe malignancy screening
pt with extensive colitis of more than 8-10 years are under surveillance programmes and undergo regular colonoscopy with multiple biopsies
what are the risk factors of IBD
more common in CD
genes implicated - NOD2 and ATG16L1
immune response
luminal microbial antigens and adjuvants
environmental smoking diet drugs stress antibiotics lifestyle pollution geography
What is the target for treating IBD
IBD - lifelong condition with no cure induction of remission maintenance of remission improved quality of life prevent bowel complications/EIM mucosal healing to decrease risk of cancer
What are the drug treatments for IBD
Aminosalicylates - 1st line Corticosteroids immunosuppressants TMPT - thiopurine methyl tranferase methotrexate biologics antibiotics
describe aminosalicylates
1st line therapy for induction of remission in UC and to decrease efficacy in CD
anti inflammatory effects - works locally not systemically
sulfasalizine-5ASA linked to sulfapyridine by diazo bond cleaved by colonic bacteria - 5ASA delivery
what is the MOA of aminosalicylates
inhibition of leukocyte movement
decrease cytokine levels and TNF
inhibition of inflammatory mediators - prostaglandins, leukotriense and PAF
what are the side effects of aminosalicylates
headaches
dizziness
fever
describe corticosteroids and state examples
induce rapid remission in CD and UC - not used long term due to side effects
used in mild/moderate disease where aminosalicylates failed
may use in conjunction with 5-ASA
examples - prednisolone, hydrocortisone, methylprednisolone
what are the long term adverse effects of corticosteroids?
HPT hyperglycaemia cataract osteoporosis osteonecrosis
describe immunosuppressants
for failed 5-ASA and pt taking chronic corticosteroids for CD and UC
- 3-6 months for effect
- MAINTENANCE not remission
what is the MOA of immunosuppressants
thiopurines - azothioprine is converted to 6-mercaptopurine to TIMP - purine analogue
TIMP is unstable and disrupts DNA synthesis in lymphocytes
cell and antibody mediated immune reactions are suppresssed
screen for TMPT enzyme polymorphism - mutation
What is TMPT?
Thiopurine methyl transferase
- enzyme responsible for metabolism of azathioprine
- individuals with no TMPT enzyme can become severely ill if treated with normal dose of thiopurine drugs - increase risk of marrow suppression and death
What is methotrexate used for?
used as alternative of azathioprine
what is the MOA of methotrexate
inhibits dihydrofolate reductase leading to suppression of inflammation and DNA synthesis.
adenosine accumulation is anti inflammatory
MXA is an anti-folate that blocks pyrimidine/purine pathway and B-cell proliferation
describe biologics and give and example
- monoclonal antibody therapy
- anti-TNF- alpha inhibitor
- inhibits signalling and cytokine production
- increase NFK beta inflammation
example - infliximab
describe antibiotics and give an example
- for mild/moderate CD treatment - maintenance
- when failed sulfasazine
