Diarrhoea (part 2) Flashcards
What is traveller’s diarrhoea?
• Traveller’s diarrhoea (TD) is defined as ≥3 unformed stools in 24 hours accompanied by at least 1 of the following: fever, nausea, vomiting, cramps, tenesmus, or bloody stools (dysentery) during a trip abroad, typically to a low- or middle-income country.
Prognosis of traveller’s diarrhoea
•It is usually a benign self-limited illness lasting 3 to 5 days.
Causes of traveller’s diarrhoea
Bacterial infections
Viral and parasitic infections may occur.
Bacterial causes of traveller’s diarrhoea
- An estimated 80% to 90% of cases are caused by the ingestion of bacterially contaminated food or water.
- Common bacterial culprits include enterotoxigenic Escherichia coli, enteroaggregative E coli, Shigella, Campylobacter jejuni, Salmonella (non-typhoid species), Yersinia, Vibrio (non-cholera species), Aeromonas, and Plesiomonas shigelloides.
-E coli is the most common pathogen, especially in Latin America.
Viral causes of traveller’s diarrhoea
•TD of viral aetiology includes rotavirus in children, norovirus (typically affecting people on cruise ships), and many enteroviral infections.
Parasitic causes of traveller’s diarrhoea
Persistent diarrhoea (>14 days) may be of parasitic origin, including Giardia, Entamoeba, Cryptosporidium, and Cyclospora infections.
Most common complication of traveller’s diarrhoea
Self-limited post-infectious irritable bowel syndrome is an even more frequent finding in returning travellers with persisting diarrhoea.
Classification of traveller’s diarrhoea
Mild (acute)
Moderate (acute)
Severe (acute)
Persistent
What is mild TD?
Diarrhoea that is tolerable, is not distressing, and does not interfere with planned activities.
What is moderate TD?
Diarrhoea that is distressing or interferes with planned activities.
What is severe TD?
Diarrhoea that is incapacitating or completely prevents planned activities; all dysentery (passage of grossly bloody stools) is considered severe.
What is persistent TD?
Diarrhoea lasting ≥2 weeks.
Hx of TD
- Presence of risk factors: age <30 years, prior TD susceptibility, chronic disease, immune compromise, travellers with prior residence in a developing country visiting friends and relatives, and travel during seasons of hot and wet climates.
- Diarrhoea (with or without tenesmus), cramping, nausea and vomiting- with resolution in 3-5days
Investigations for TD
- Stool culture
- Stool occult blood
- Stool ova and parasite examination
Differentials of TD
- IBS- Diarrhoea or constipation, both associated with abdominal pain. No weight loss, fever, or systemic symptoms. Symptom relief usually occurs after bowel movement. Post-TD irritable bowel syndrome (IBS) is usually of the diarrhoea subtype (IBS-D).
- Malabsorptive conditions- persistent diarrhoea
- Coeliac disease- Persisting diarrhoea with malabsorption (with or without travel history). May be associated with dermatitis herpetiformis.
- Crohn’s disease- diarrhoea, abdominal pain, fever, perianal distulae
- Ulcerative colitis- Bloody diarrhoea (with or without travel history), abdominal pain, fever, no perianal disease.
