Inflammatory Bowel Disease Flashcards
Inflammatory bowel disease mainly comprises of two idiopathic chronic inflammatory diseases - what are they?
Crohn’s disease
Ulcerative colitis
Which 3 factors link together in the pathogenesis of IBD?
Genetic predisposition
Impaired mucosal immunity
Environmental triggers
There is a stronger genetic link in UC than Crohn’s disease. True/False?
False
Stronger genetic link in Crohn’s (36%) than UC (16%)
Which gene is susceptible to mutation which causes inflammatory bowel disease?
NOD2 (IBD-1) on chromosome 16
Encodes protein involved in bacterial recognition
Crohn’s disease a TH1/TH2/TH1+TH2 mediated disease
TH1-mediated disease
UC is a TH1/TH2/TH1+TH2 mediated disease
(mixed) TH1 + TH2 -mediated disease
Smoking aggravates Crohn’s disease + UC. True/False?
False
Aggravates Crohn’s but no effect on/may even protect UC
Which age range is typical peak incidence of UC?
20-40s but variable
Where does the inflammation start in UC?
Rectum
Does UC produce skip lesions?
No
Continuous proximal inflammation from rectum to stop point
List typical symptoms of UC
Diarrhoea + bleeding Increased bowel frequency Urgency, tenesmus, incontinence Night rising Lower abdo pain (LIF)
Define severe UC
>6 bloody stools/day + 1 of: Fever Tachycardia Anaemia Elevated ESR
What is the classic sign of mucosal inflammation/oedema on an AXR?
Thumbprinting
How does toxic megacolon arise?
Persistent inflammation causes loss of muscle tone of the colon, resulting in distention
What are some extra-intestinal manifestations of UC?
Primary sclerosing cholangitis
Apthous ulcers
Erythema nodosum
Uveitis
Which age range is typical for Crohn’s disease?
Young children to 40 year olds
The inflammation in Crohn’s and UC is transmural, i.e. it breaches the mucosa and goes beyond muscle layer. True/False?
False
Inflammation in Crohn’s is transmural; inflammation in UC is confined to mucosa/submucosa
Does Crohn’s disease produce skip lesions?
Yes
Can affect anywhere from mouth to anus
Can fistulas occur in Crohn’s and UC?
Yes
Leads to abscess formations, especially peri-anally
Symptoms of Crohn’s disease are dependent on where the disease occurs. List some common symptoms
Abdominal cramps Diarrhoea Weight loss Painful ulcers Abscesses
How common is granuloma in Crohn’s disease?
50% of patients
Where does Crohn’s disease most commonly occur?
Terminal ileum
Colon
Fissures are associated with which IBD - Crohn’s or UC?
Crohn’s disease
Deep, knife-like fissures
List some complications of Crohn’s disease
Malabsorption
Short bowel syndrome
Vitamin deficiencies, anaemia
Fistulas
What are the 4 treatments available (excluding surgery) for UC and Crohn’s disease, in order of step-up therapy?
5-ASA (mesalazine - UC ONLY)
Steroids
Immunosuppression
Anti-TNF drugs
How can mesalazine be administered?
Orally
Topically as a rectal suppository/enema
What is the main action of mesalazine?
Anti-inflammatory
Mesalazine can be given in an oral form that is “pH-dependent” - what does this mean?
Only activates at a certain pH; in this case, would only activate in the presence of the pH of the colon
What is the advantage of a mesalazine topical enema over a suppository?
Enema extends action to sigmoid colon
What is the advantage of a mesalazine topical suppository over an enema?
Suppository has better mucosal adherence
If mesalazine is ineffective/patient continues to experience symptoms, which class of drugs is prescribed? Give an example of the class of drug used
Steroids
Oral/topical prednisolone/budesonide
Steroids are given for a long course in IBD. True/False?
False
Is increasing or reducing dosage of steroids given for IBD?
Reducing dose (start high and reduce over 6-8 weeks)
When a more potent suppression of inflammation than steroids is required, which class of drugs is prescribed? Give an example of this class of drug
Immunosuppression
Azathioprine, Methotrexate
Which class of drug is used after immunosuppression? Give an example of a drug of this class
Anti-TNF drugs
IV Infliximab
Anti-TNF has become the mainstay of treating Crohn’s disease. When is it mainly used, according to NICE?
Long-term management
Refractory/fistulating disease
BUT NOT IN PRESENCE OF TB
What are “planned” surgical procedures for IBD in cases of emergency?
Subtotal colectomy (leave rectum) in UC Resection in Crohn's disease
List elective surgery for Crohn’s disease
Resection
Stricturoplasty
Fistula repair
List elective surgery for UC
Proctocolectomy with end ileostomy
Proctocolectomy with ileorectal anastomosis
Proctocolectomy with pouch
What is an ileostomy?
Small intestine is diverted to an opening in the abdomen and a bag is placed externally to collect waste products
What is a pouch? (AKA ileo-anal pouch; J/W/S pouch)
Loops of small intestine are folded and stapled on itself to create a reservoir, restoring normal function of the rectum
Surgery for UC is well tolerated. True/False?
True
Most live well with a stoma
Surgery for Crohn’s is well tolerated. True/False?
False