Gastroenterology: Crohn's Disease Flashcards
What percentage of those with IBD present in childhood or adolescence?
Approximately 1/4
Is Crohn’s or ulcerative colitis more common in children?
Crohn’s disease (in contrast to the adult population)
Can Crohn’s affect any part of the GI tract?
Yes - from mouth to anus
How can Crohn’s present in children and adolescents?
Classical presentation (25%): abdominal pain, diarrhoea, weight loss
Growth failure
Puberty delayed
General ill health: fever, lethargy, weight loss
Extra intestinal presentations
What extra intestinal presentations can occur?
Oral lesions Perianal skin tags Uveitis Arthralgia Erythema nodosum
How does erythema nodosum present?
Tender, red, subcutaneous nodules on the shins
3-20cm
Erupt over 1 to several weeks
Can it present as lethargy and general ill health without GI symptoms?
Yes particularly in older children
What may it mimic?
Anorexia nervosa
Psychological problems
What blood tests are helpful in making a diagnosis?
Raised inflammatory markers - platelet count, erythrocyte sedimentation rate (ESR) and CRP
Iron deficiency anaemia
Low serum albumin
How would you describe Crohn’s disease?
A chronic inflammatory disease
Is the inflammatory process transmural?
Yes - it is deeper than in UC
What are skip lesions?
Patches of unaffected bowel between areas of active disease
Where does it most commonly affect?
Distal ileum and proximal colon
Describe what occurs initially
Areas of acutely inflamed, thickened bowel.
Subsequently strictures of the bowel and fistula may develop - between adjacent bowel, bowel and skin or bowel to other organs e.g vagina or bladder
What is diagnosis based on?
Endoscopic and histological findings on biopsy
Upper GI endoscopy, ileocolonoscopy and small bowel imaging required
What is the histological hallmark?
Non-caseating epitheliod cell gramulomata (although this is not identified in up to 30% at presentation)
What may small bowel imaging reveal?
Narrowing, fissuring, mucosal irregularities, bowel wall thickening
How is remission induced?
Nutritional therapy - normal diet replaced by whole protein modular feeds (polymeric diet) for 6-8 weeks
- effective in 75% cases
Systemic steroids required if ineffective
Is relapse common?
Yes
What is almost always required to maintain remission?
Immunosuppressant medication - azathioprine, mercaptopurine, methotrexate
When conventional treatment failed: anti tumour necrosis factor agents - infliximab, adalimumab
What is useful to correct growth failure?
Long term supplemental enteral nutrition - often overnight NG or gastrostomy feeds
How are complications often managed e.g obstruction, fistula, abscess formation , severe unresponsive localised disease ?
Surgery
What are the side effects and risk of short term systemic steroids?
Rarely serous if prescribed for 1 month or less
Sleep disturbance
Increased appetite
Weight gain
Increased postprandial blood sugar
Psychological effects including decreased energy
Rare: infection, HF, peptic ulcer, DM, a vascular necrosis of hip, mania/depression with suicidal intent/ psychosis/delirium
What are the side effects of long term systemic steroids?
Infections HTN DM Osteoporosis Avascular necrosis Myopathy Cataracts Glaucoma
What are side effects of azathioprine?
Infection Bone marrow suppression Leukopenia Pancreatitis Thrombocytopenia
Uncommon: anaemia, hepatic disorder, hypersensitivity
What monitoring should be done with azathioprine?
FBC weekly for first 4 weeks then at least every 3 months (checking for myelosuppression)
What is the frequency of dosage for methotrexate?
Weekly
What contraindications are there for methotrexate?
Active infection
Ascites
Immunodeficiency syndromes
Pleural effusion
What side effects of methotrexate (oral) are there?
Neurotoxicity
Necrotising demyelinating leukoencephalopathy
Anaemia Leukopenia Thrombocytopenia Increased infection risk Abdominal discomfort, diarrhoea, nausea Headache Oral disorders Respiratory disorders
