gastrointestinal infections/disorders Flashcards
What can cause infectious diarrhoea
Clostridium difficile
E coli
shigella
Salmonella spp
causes of non-infectious diarrhoea
Antibiotics side effects Post-infectious IBS Inflammatory bowel disease Microscopic or ischaemic colitis Coeliac disease
Where does C. Difficile typically colonise
Colon
What effect do C. difficile toxins have
Cytotoxic effect on enterocytes which results in excessive fluid leakage from intestinal epithelium and patchy necrosis
symptoms associated with a C. difficile infection
Diarrhoea -> Dehydration, dry oral mucosa and reduced skin turgor
Abdominal pain - severe in fulminant colitis
Fever
Abdominal tenderness
investigation results of suspected C.diff
Elevated WBC
Raised CRP, low albumin
Abdominal X-ray reveals colonic dilation
Stool cultures confirm toxins A and B and occult blood
management of C diff infection generally
isolate patient in side room
discontinue antibiotics
fluid and nutritional management
oral/IV vancomycin
What is ischaemic colitis
occurs when there is an acute, transient compromise in blood flow, below required for metabolic demands of the colon
• Mucosal ulcers
• Inflammation
• Haemorrhage
associated symptoms with fulminant colitis (most severe colitis - most severe C diff infection)
Hypotension, or shock,
ileus,
toxic megacolon
management of non severe c diff
oral vancomycin/metronidazole
faecal microbiota transplantation - usually if recurrent, persistent or prolonged infections
management of severe c diff/fulminant colitis
antibiotics
supportive care and close monitoring
surgery consultation
What is a toxic megacolon
inflammation of deeper layers of colon therefore it stops working and dilates
Dilated bowel detected on radiograph, distention of bowel as the colon is unable to adequately remove gas of faeces from the body
Risk of colonic rupture
first line of treatment for a toxic megacolon
Antibiotic and supportive management
Patient is transferred to ITU for invasive monitoring:
• IV fluid resuscitation and inotropic support (noradrenaline for bp)
• 4-8 weeks of oral vancomycin to completely resolve infection.
indications for surgery in a patient with a toxic megacolon
Colonic perforation
Necrosis of full-thickness ischaemia
Intra-abdominal hypertension or abdominal compartment syndrome
signs of peritonitis or worsening abdominal exam despite adequate medical therapy
end-organ failure
What is pseudomembranous colitis in C diff
- Toxins A and B potentiate an inflammatory response within the large intestine that increases vascular permeability and pseudomembrane formation.
- Distinct appearance – adherent raised yellow and white plaques against an inflamed mucosa
- Confirmed by endoscopy +/- biopsy
