Crohn's disease Flashcards
Crohn’s Disease: Definition
- chronic
- relapsing
- inflammatory bowel disease
- transmural granulatomous inflammation
- can affect any part of the GI tract from mouth to anus
MOSTLY AFFECTS ILEUM - leading to fistula formation or stricturing
Crohn’s Disease: Epidemiology
- Has a bimodal incidence (15-30 and 60-80)
- more common in caucasian and jews
Crohn’s Disease: Key Presentation
Diarrhoea with or without blood, abdo pain, weight loss, fatigue, fever
Crohn’s Disease: Main aetiology?
- Smoking increases the risk
- associated with the NOD-2 gene
Crohn’s Disease: What gene mutuation is it associated with?
NOD-2 (which is involved in Immune surveillance)
Crohn’s Disease: What parts of the GI tract can it affect?
Any part - from mouth to anus
pathology
- pathogens pass through lining of GI tract
- into mucosa
- bacteria stimulate the Th cells to release cytokines
- inflammation
main pathologies seen with crohns
CROHNS
C - cobblestone appearance
R - rosethorn ulcers
O - obstruction
H - hyperplasia (lymph nodes)
N - narrowing of lumen
S - skip lesions (patchy wound)
bowel wall thickening, lumen narrowing, deep ulcers, fistulae and fissures may also be seen
signs
Pyrexia - fever
Dehydration
Angular stomatitis - inflam at corners of mouth
Aphthous ulcers -Inside the mouth
Episcleritis and Uveitis - blood shot eyes
Pallor
Tachycardia
Hypotension
Abdominal pain, mass and distension
cachectic + pale - anaemia
RLQ tenderness
right iliac fossa mass
Kantor’s String Sign
perineal skin tags, fistulae or perianal abcess
erythra nodosum
pyoderma gangrenosum
amloidosis
symptoms
Nausea & vomiting
Fatigue
Low-grade fever
Weight loss
Abdominal pain
Diarrhoea (+/- blood - less common in Crohn’s than UC )
Rectal bleeding
Perianal disease
first line investigations
- Routine bloods - Serum ACE will be raised
- CRP/ESR - if raised shows inflammation
- Faecal calprotectin - >90%
P-ACNA - negative in Crohns but present in UC
other:
- stool culture - exclude infection
- raised WCC
- anaemia
- low albumin
- thrombocytosis
gold standard investigation
Endoscopy with biopsy
Colonoscopy - for colon and terminal ileum
Upper GI endoscopy - in patients with gastroduodenal disease
when is surgery used as an investigation
for patients with associated perianal fistulas
1st line management - inducing remission (containing disease)
Moderate-Severe :
- Oral Prednisolone
- IV hydrocortisone
Mild-Moderate:
- Budesonide (minimal systemic absorption)
- Exclusive enteral nutrition (EEN)
2nd line management - when steroids arent suitable - inducing remission
2 or more exacerbations in 12 months:
Add immunosuppressants (specialist guidance):
- Azathioprine + mercaptopurine
ASSESS TPMT - RISK OF BONE MARROW SUPPRESSION
- Methotrexate - if intolerant to prev 2
- Infliximab + Adalimumab - evidence of significant and/or extensive disease or other poor prognostic features
- ASSESS CXR - RISK OF REACTIVATING LATENT TB
Crohn’s Disease: Complications
MSK:
- Arthritis
Skin:
- Erythema nodosum - red bruise looking
- Pyoderma gangrenosum
Eyes and mouth:
- Episcleritis
- Conjunctivitis
- Aphthous ulcers (mouth ulcer)
Hepatobiliary:
- Fatty liver disease and gall stones
Other:
surgery
- 8/10 patients have at least one operation during disease course
- Indications -
- Localised CD eg ileocecal especially if don’t want meds or failing to respond
- Managing Complications - perforation, abscess formation etc
- rarely curative
- control fistulae
- resection of strictures
- rest / defunctioning of bowel
managing perianal disease
Surgery + Pharmacological Therapy
Control perianal sepsis - e.g. antibiotics
Evaluation - e.g. MRI or examination under anaesthesia
Surgical intervention - e.g. abscess drainage or seton for fistula
Initiation or escalation of medical therapy
Complex surgical planning - may be required for fistula’s not responding to initial therapy.
if a patient was to have a chrons flare up, what would be some clinical findings
feel unwell
raised caroprotein
most important lifestyle factor in chrones
smoking
abdominal tenderness and bowel sounds
yes to both
aetiology
Inappropriate reaction to gut flora
- family history
- smoking 3X inc risk
- diets high in refined carbs and fats
management of peri-anal fistulae
- drainage seton - string threaded through fistulae into anal canal and fastened in a loop - prevent division of sphincter muscles
- fistulotomy - low risk of incontinance - disecting tissue, opening fistula
- sphincter saving methods - fibrin glue + fistula plug
management of perianal abcess
- IV ceftriaxone + metronidazole
- examination, insision + draining under aneathetic
common happenings after ileum surgery
decreased vitamins, mineral and fat absorbtion
- presents with diarrhoea and fatty stools
often called short bowel syndrome
submucosal fibrosis
from the granulotomas
what location of chrons causes gallstone development
terminal ileum bc it effects uptake of bile salts
complication of crohns which causes bubbles in urine
Colovesical fistula
interaction of azothioprine and allupurinol
increased risk of leukopenia
xanthine oxidase inhibition
imparing metabolism of azathioprine
imatinib
inhibition of tyrosine kinase
high risk complication
renal stones
