Food Poisoning/Acute Infectious Diarrhoea Flashcards
Define acute infectious diarrhoea
Ingestion of food/water contaminated with bacteria, viruses, parasites or chemicals
Typically food poisoning is…..
- Mild
- Self-limiting
3 biggest causes of acute infectious diarrhoea in the UK
- Campylobactor
- Clostridium perfringens
- Norovirus
3 biggest causes of food poisoning globally
- Shigella
- Salmonella
- Campylobacter
Common cause of food poisoning in developed countries
STEC - Shiga toxin producing E.coli
Common cause of food poisoning in developing countries
Entamoeba histolytica
Seasonal peaks - food poisoning - generally peaks in…
Summer
Describe the mechanism of enterotoxins
- Influence secretory mechanisms of the mucosa of the SI
- LI = invasive and destructive - inflammation
- SI or LI = non-inflammatory, no invasion
Mechanism of subtypes of food poisoning causing vomiting
Toxins act on the CNS
Bacteria causing botulism
Clostridium botulinum
- Inhibits ACh release in nerve endings
Food poisoning - small bowel pathogen
Watery diarrhoea
Food poisoning - large bowel pathogen
Inflammatory diarrhoea - fever, bloody mucoid stool (invasion of mucosa)
Non-infectious causes of diarrhoea
- ADR
- Food allergies
- IBD
- Thyrotoxicosis
- Carcinoid syndrome (paraneoplasm)
3 subtypes of diarrhoea
- Acute watery (several hours - days)
- Acute bloody
- Persistent (14+ days)
2 subtypes of dehydration
- No dehydration
- Some dehydration - 2+ signs - thirst, restlessness, irritable, decreased skin elasticity, sunken eyes
- Severe dehydration
Dehydration is less likely with ….. diarrhoea
- Inflammatory diarrhoea
smaller stool volume
Other, more rare systemic symptoms of infectious diarrhoea
- Skin macules
- Reactive arthritis
- Neurological - diplopiea, decreased muscle tone, slurred speech
Investigations for infectious diarrhoea
- Stool microscopy
- Stool culture
- Stool O and P (ova and parasite)
- FBC
- Serum creatinine and electrolytes
Risk factors for infectious diarrhoea
- Old/children
- Pregnant
- Chronic disease
- Recent travel history
- Immunocompromised
- Contact history
- Consumption of uncooked meat/seafood
- Use of antacids
DDX for infectious diarrhoea
- Acute viral syndromes
- Crohn’s disease
- Ulcerative colitis
- Food allergies/intolerance
- IBS
- Microscopic colitis
- Acute appendicitis
- Cholecystitis
- Pancreatitis
Management/treatment for infectious diarrhoea
- Oral rehydratio nfluids
- Symptom control
- Electrolyte replacement
*** antiemetics are not indicated for infectious diarrhoea
Mild moderate diarrhoea treatment
- Oral rehydration
- Antiperistaltics (opiate derivatives) - for watery diarrhoea
- Antidiarrhoeals (Aluminium hydroxide, Bismuth subsalicylate, Loperamide)
Aluminium hydroxide is an….
Absorbent
Bismuth is a….
Antisecretory
