IBD Flashcards
The incidence of Crohn’s disease is higher in the Western world (i.e. UK, Europe and America) than the rest of the world. TRUE/FALSE?
TRUE
What can be used to prove that there are genetic links in IBD?
- Twin studies
- Affected 1st degree relatives
What genetic mutation is present in 10-20% of caucasians with Crohn’s disease? What does it cause?
NOD2/ CARD15 (IBD-1)
=> Encodes a protein involved in bacterial recognition
How can adaptive immunity of the mucosa be affected by abnormal T cell function?
Overactive effector T-cells → Inflammation/ Disease
Absence of regulatory T-cells → Uncontrolled Inflammation/ Aggressive Disease
What cells of the adaptive immune system cause Crohn’s disease, and which cause UC?
Crohn's = Th1 mediated UC = Mixed Th1/ Th2 or NKCs
Does smoking aggravate Crohn’s or UC?
Aggravates Crohn’s disease but protects against UC
Describe the typical clinical presentation of UC?
- Female 20-30s
- Relapsing course
- Affects rectum extending proximally
How is UC referred to if it only affects a) the rectum? b) the rectum and left-side of the colon? c) the entire colon?
a) Proctitis
b) Left-sided colitis
c) pancolitis
What symptoms are usually present in UC?
- Diarrhoea + bleeding
- Increased bowel frequency
- Urgency
- Tenesmus (incomplete emptying)
- Incontinence
- Night rising
- Lower abdo pain (esp. LIF)
What should you remember to check in patient’s history if you suspect UC?
- Recent travel
- Antibiotics
- NSAID’s
- Family history
- Smoking
- Skin, eyes, joints
What criteria is used to assess the severity of UC, and why is this scoring important?
Truelove and Witt criteria: >6 bloody stools/24 hour \+ 1 or more of: - Fever (>37.8°C) - Tachycardia (>90/min) - Anaemia (Haemoglobin <10.5g/dl) - Elevated ESR (>30mm/hr)
Important as Severe UC = 30% risk of colectomy
What investigations can be used if you suspect UC?
- C-reactive protein (CRP)
- Albumin (a negative acute phase reactant)
- Plain AXR
- Endoscopy
- Histology
What can an AXR show you that would point towards a diagnosis of UC?
- Stool distribution = Absent in inflammed colon
- Mucosal oedema / ‘thumb-printing’
- Toxic megacolon:
=> Transverse >5.5cm
=> Caecum >9cm
What signs at endoscopy indicate UC is present?
Loss of vessel pattern
Granular mucosa
Contact bleeding
What signs on histology indicate UC is present rather than normal mucosa?
- lack of goblet cells
- crypt distortion
- formation of abscesses (due to crypts closing at surface)
What complications can arise from UC?
Increased risk of colorectal cancer
- depends on severity and extent of disease
What extra-intestinal manifestations are common in UC?
- Skin - erythema nodosum/ pyoderma gangrenosum
- Joint arthritis
- Eyes (uveitis)
- Deranged LFTs, gallstones/ PSC
- Oxalate renal stones
PSC is more commonly associated with UC than Crohn’s. TRUE/FALSE?
TRUE
- 80% of those with PSC have associated IBD
When does Crohn’s disease normally present?
90% onset before age 40
Describe the normal clinical appearance of Crohn’s which distinguishes it from UC?
- Affects any region of GI tract from mouth to anus
=> Skip lesions - Transmural inflammation (all the way through wall)
What peri-anal disease is common in Crohn’s ?
- Recurrent abscess formation
- Pain
- fistula with persistent leakage
- Damaged sphincters
Resections to treat Crohn’s disease are minimised as they are NOT curative. TRUE/FALSE?
TRUE
- many patients require multiple surgeries
What symptoms can patients with Crohn’s disease experience?
Small intestine disease:
- Abdominal cramps (peri-umbilical)
- Diarrhoea
- Weight loss
Colon:
- Cramps (lower abdomen)
- Diarrhoea with blood
- Wt loss
Mouth:
- Painful ulcers
- swollen lips
- angular chielitis
Anus:
- peri-anal pain
- abscess
What may you notice on examination of a patient with suspected Crohn’s disease?
- Evidence of wt loss
- RIF mass
- peri-anal signs
