Gastroenterology Flashcards
Crohn’s Disease (IBD)
Risk Factors
Clinical Features
Investigations
Imaging
1.) Risk Factors
- age (15-30/60-80), smoking, FH of IBD
- white European, appendicectomy
2.) Clinical Features - episodic abdominal pain and chronic diarrhoea which may contain blood or mucus
- most common symptom: diarrhoea in adults, abdo pain in children
- pain can be anywhere but is most common in RLQ
- malaise, malabsorption, weight loss
- oral aphthous ulcers, perianal disease
- extra-intestinal features: arthritis (most common), skin conditions such as erythema nodosum or pyoderma gangrenosum, uveitis, failure to thrive in children, HPB disease (esp gallstones), kidney stones
3.) Investigations
- routine bloods: anaemia, low albumin, inflammation
- stool sample, faecal calprotectin
- proctosigmoidoscopy for perianal fistulae
4.) Imaging
- colonoscopy: skip lesions, ‘cobblestone’ appearance
- histology: ↑goblet cells, non-caseating granulomas
- CT-AP: for bowel obstruction, perforation, fistulae
- MRI: MREnterography for SI involvement and enteric fistulae, MRI-Rectum for peri-anal disease
Management and Complications of Crohn’s Disease
Inducing Remission
Maintaining Remission
Surgical Intervention
GI Complications
Extraintestinal Complications
1.) Inducing Remission - for acute attacks
- IV fluids (resus), nutritional support
- prophylactic heparin (IBD is pro-thrombotic)
- IV hydrocortisone 100mg QDS for 3-5d (very unwell)
- steroids are also given topically (enemas) or orally (pred)
2.) Maintaining Remission
- 1°azathioprine or mercaptopurine
- biologics (infliximab, first line for perianal or fistulating Crohn’s)
- rescue therapy: biologics or surgery
3.) Surgical Intervention - often bowel resections
- reasons: failed medical management, severe complications, growth impairment in children
4.) GI Complications
- fistulas, strictures, recurrent perianal abscesses
- GI malignancy: colorectal cancer, small bowel cancer
5.) Extraintestinal Complications - due to malabsorption
- growth delay in children, osteoporosis
- ↑risk of gallstones and renal stones
Ulcerative Colitis (IBD)
Risk Factors
Clinical Features
Investigations
Imaging
1.) Risk Factors
- age (15-25/55-65), FH of IBD
- smoking is a protective factor (reduces risk)
2.) Clinical Features - bloody diarrhoea
- change in bowel habits: PR bleed, mucus discharge, ↑frequency, urgency of defecation, tenesmus
- dehydration, malaise, low-grade fever, anorexia
- abdominal pain for complications: toxic megacolon, perforation, fulminant colitis, peritonitis
- extra-intestinal: primary sclerosing cholangitis
3.) Investigations
- routine bloods: anaemia, low albumin, inflammation
- LFTs deranged in patients on medical treatment
- clotting can be deranged in severe attacks
- stool sample, faecal calprotectin
4.) Imaging
- colonoscopy (gold): continuous, pseudopolypoid
- flexible sigmoidoscopy is preferred in severe episodes of colitis due to reduced risk of bowel perforation
- histology: ↓goblet cells, crypt abscesses
- acute exacerbations: AXR (thumbprinting) or CT for complications
- AXR to rule out toxic megacolon
Management and Complications of Ulcerative Colitis
Induce Remission
Maintain Remission
Surgical Intervention
Complications
1.) Induce Remission - for acute attacks
- severity: mild = <4 bloody stools/day, moderate: 4-6 bloody stools/day, severe: 6+ inc systemic sx
- mild-mod: PR mesalazine (4wks) –> add PO mesalazine (PO+PR mesalazine if the disease spreads past the left colon) –> topical or PO prednisolone
- severe: IV hydrocortisone 100mg QDS for 3-5d
- IV fluids (resus), nutritional support
- prophylactic heparin (IBD is pro-thrombotic)
2.) Maintain Remission
- 1°PR +/- PO mesalazine (aminosalicylate)
- 2°PO azathioprine OR PO mercaptopurine: severe relapse OR >=2 exacerbations in the past year
- rescue therapy: cyclosporin, biologics, surgery
3.) Surgical Intervention - often bowel resections
- reasons: failed medical management, toxic megacolon, bowel perforation, ↓risk of carcinoma
- total proctocolectomy is curative
4.) Complications
- toxic megacolon: severe abdo pain and distension, w/ pyrexia and systemic toxicity need decompression
- colorectal carcinoma: undergoing screening 10yrs from diagnosis
- osteoporosis
- pouchitis: inflammation of ileal pouch
Dysphagia
Oesophageal Dysphagia
Oropharyngeal Dysphagia
1.) Oesophageal Dysphagia - food stuck in the throat
- obstruction: tumour, stricture, inflammation, can be classed as extraluminal, intraluminal, or luminal
- neuromuscular: presbyoesophagus (abnormal shape), achalasia, dysmotility
- OGD used to exclude obstructive causes
- barium swallow or manometry for neuromuscular
2.) Oropharyngeal Dysphagia - food can’t enter throat
- problems with tongue muscle coordination
- often as a result of neurological disease e.g. stroke
- video-fluoroscopy can be used to assess swallowing
- may need enteral feeding tube if unsafe swallowing
Routes of Enteral Feeding
Oral
Nasogastric
Nasojejunal
Gastrostomy
Jejunostomy
1.) Oral - if normal GI tract
2.) Nasogastric - tube feeding into the stomach
- for patients unable to tolerate swallowing
3.) Nasojejunal - tube feeding into the jejunum
- upper GI dysfunction or inaccessible upper GI tract
4.) Gastrostomy - surgical or PEG (percutaneous endoscopic gastrostomy)
- for long term (4wks+) enteral tube feeding
5.) Jejunostomy - stoma into jejunum
- alternative to gastrostomy
Total Parenteral Nutrition
What is it?
Complications/Regular Monitoring
Thiamine Deficiency
1.) What Is It?
- contains a mix of fluid, macro/micronutrients
- if the GI tract is inaccessible or not working
- given via dedicated central line (PICC or Hickman)
2.) Complications/Regular Monitoring
- infection: 4hrly obs, line/dressing inspection
- hyperglycaemia: high sugar content, check BM
- fluid imbalance: accurate fluid balance recording
- electrolyte imbalances: daily U&Es
3.) Thiamine Deficiency - due to starvation
- thiamine is needed to process food
- causes Wernicke’s encephalopathy: confusion, ataxia, ophthalmoplegia
- if untreated —> Korsakoff’s psychosis —> dementia
- IV Pabrinex (mix of vitB and vitC) given for prevention
Coeliac’s Disease
Pathophysiology
Gastrointestinal Features
Extra-Intestinal Features
Differential Diagnoses
1.) Pathophysiology - T cell-mediated immune reaction to the gliadin fraction of gluten causes damage to the villi in the small intestine which causes malabsorption
- antibodies are anti-TTG and anti-EMA (both IgA)
- associated w/ other autoimmune conditions: T1 DM, thyroid disease, autoimmune hepatitis, PBC, PSC
- also associated with Turner’s and Down syndrome
- can present in at any age (early childhood common)
2.) Gastrointestinal Features - classical form, presents from 9-24mths of ages w/ features of malabsorption:
- diarrhoea, steatorrhoea (foul smelling)
- abdominal pain and distension/bloating
- failure to thrive, weight loss/anorexia, muscle wasting (often buttocks)
3.) Extra-Intestinal Features - atypical form
- dermatitis herpetiformis (itchy skin rash on abdomen): treat with topical dapsone
- anaemia (↓iron/B12/folate), osteoporosis (↓Vit D)
- neuro: peripheral neuropathy, epilepsy, ataxia
- short stature, delayed puberty, infertility
- functional hyposplenism: ↑risk of infections
- arthritis, liver and biliary tract disease
- poor control/gluten diet can lead to the development of enteropathy T-cell lymphoma (NHL)
4.) Differential Diagnosis
- cystic fibrosis, IBD, post-gastroenteritis, autoimmune enteropathy, eosinophilic enteritis, tropical sprue
Management of Coeliac Disease
Criteria for Serological Investigation
Investigations
Management
1.) Criteria for Serological Investigation
- persistent unexplained abdominal or GI symptoms
- faltering growth, prolonged fatigue, unexpected weight loss, severe or persistent mouth ulcers
- unexplained iron, vitamin B12 or folate deficiency
- at diagnosis of type 1 diabetes, autoimmune thyroid disease, IBS in adults
- first‑degree relatives of people with coeliac disease
2.) Investigations - serology is only accurate if gluten has been in the diet for at least 6wks before testing
- test for total IgA and anti-tTG, if anti-tTG is weakly positive OR total IgA is deficient, use anti-EMA
- is serology is +ve, endoscopic intestinal/duodenal biopsy is carried out which should show ↑inflammatory cells, crypt hyperplasia, villous atrophy (severe)
3.) Management - a lifelong diet free of gluten
- gluten-free diet: avoid wheat, barley, rye, oats
- diet supplements if obvious malabsorption e.g. iron
- annual follow up to check for sx, diet compliance, development, growth and long term complications
- anti-TTG can be monitored to check compliance
- pneumococcal vaccination every 5 years
Oesophageal Conditions
Dissection of thoracic aorta
Diffuse oesophageal spasm
Gastro-oesphageal reflux
Boerhaaves syndrome
Achalasia
Clostridium Difficile
Pseudomembranous Colitis
Clinical Features
Investigations
Management
Complications
1.) Pseudomembranous Colitis
- occurs after normal gut flora are suppressed by broad-spectrum antibiotics (cephalosporins, clindamycin)
- increased risk in patient on a PPI
- can affect any part of the colon
- opportunistic: elderly and immunosuppressed
- C diff can be found in up to 25% of asymptomatic hospitalised patients on antibiotics
2.) Clinical Features
- abdominal pain, profuse diarrhoea, fever
- raised WCC is characteristic but can be normal in mild disease
- severe disease: temp >38.3, WCC >15, raised CRP, AKI, albumin <25, endoscopic or radiologic evidence of severe colitis
3.) Investigations
- bloods: FBC, CRP, U+Es, clotting, blood cultures
- stool sample: +ve for C diff. toxin A/B AND antigen
- AXR: thumbprinting and mucosal oedema, also to exclude toxic megacolon
- CXR: to exclude perforation (pneumoperitoneum)
- sigmoidoscopy: pseudomembrane formation
4.) Management
- treat the patient in a side room
- IV fluids, analgesia, stop/change current antibiotics
- first episode: PO vancomycin for 10d
- recurrent episode: PO fidaxomicin (if w/in 12 wks of previous episode)
- life-threatening: PO vancomycin + IV metronidazole, consider surgery
- vancomycin is given orally because it is no oral bioavailability so it remains in the colon for it to take effect
- avoid opiates and anti-diarrhoeal medications
5.) Complications
- toxic megacolon, perforation/peritonitis, sepsis
- AKI, hypoalbuminaemia, hypokalaemia
