Viral gastroenteritis Flashcards
Define gastroenteritis
Transient disorder due to enteric infection with viruses, bacteria or parasites
Define food poisoning
illness caused by the consumption of food or water contaminated with bacteria and/or their toxins, or viruses, parasites, or chemicals
Define dysentery
acute infectious gastroenteritis characterised by diarrhoea with blood and mucus
Define outbreak
Two or more cases associated in time and place
Define traveller’s diarrhoea
developing diarrhoea at a destination abroad with at least one additional symptom (abdominal cramps, tenesmus, nausea, vomiting, fever, faecal urgency), involves travel from LMICs
What are the causes of gastroenteritis
Most commonly self-limiting viruses
Faeco-oral, foodbornes, environmental transmission
Viruses: rotavirus, norovirus, adenovirus
Bacteria: Campylobacter, E. Coli, salmonella, Shigella, Yersinia
Parasites: Cyrptosporidiosis, entamoeba, giardia
What are the symptoms and signs of gastroenteritis
Diarrhoea (sudden onset, ± blood, mucous, faecal urgency)
Nausea and vomiting
Fever
Abdo pain and cramps
General malaise
Headache, myalgia, bloating, flatulence, weight loss, malabsorption
Define acute diarrhoea
3 or more episodes of liquid or semi-liquid stool in a 24h period, <14 days
What investigations should be done for gastroenteritis
Bedside: stool culture, ova and parasite testing
Bloods: FBC, U&Es, glucose, blood cultures
What necessitates hospital admission for gastroenteritis
Systemically unwell and/or there are clinical features suggesting sever dehydration and/or progression to shock
There is intractable or bilious vomiting
Acute-onset painful, bloody diarrhoea
Confirmed STEC infection O157
Suspected serious complication e.g. HUS, sepsis
What is the management for gastroenteritis
Assess dehydration status
Not dehydrated → continue with usual feeds, regular fluid intake, avoid fruit juice/carbonated drinks, consider ORS if at risk
Dehydrated → oral rehydration solution (ORS) + advice (above), consider IV fluids if persistently vomiting
- ≤ 5 years: 50mL/kg over 4 hours
- > 5 years: 200mL after each loose stool (in addition to normal fluid intake)
Shock → admit + Immediate IV resuscitation (IV 0.9% Saline 20mL/kg over < 10 minutes)
Consider notifying the local health protection team
Prevention of transmission
What advice should be given regarding preventing transmission of gastroenteritis
Always flush if possible
Handle potties with gloves, wash with hot water and detergent
Wash hands after going to the toilet and changing nappies
Clean toilet seats, flush handles, wash-hand basin taps, surfaces, and toilet door handles once a day
Do not share towels and bathwater
Wash soiled clothing and bedding at a high temperature
School exclusion until at least 48 hours after the last episode
No swimming (for 2 weeks if cryptosporidiosis or giardiasis suspected)
What are the complications of gastroenteritis
Dehydration, electrolyte disturbance, AKI
Acquired or secondary lactose intolerance (post gastroenteritis syndrome)
Haemolytic uraemia syndrome
Thrombotic thrombocytopenic purpura
Reactive arthritis (Reiter’’s)
Sepsis
Toxic megacolon
Pancreatitis, sclerosing cholangitis, liver cirrhosis
Faltering growth
Irritable bowel syndrome
Inflammatory bowel syndrome
Guillain Barre (campylobacter)
What is the prognosis for gastroenteritis
Diarrhoea usually lasts 5–7 days, and in most children stops within 2 weeks.
Vomiting usually lasts 1–2 days, and in most children stops within 3 days.
Describe clostridium perfringens infection
Causes food poisoning
Usually caused by inadequate storage and insufficient reheating of contaminated meat dishes or cooked meats or meat products e.g. institutional catering settings
Describe bacillus cereus infection
Causes food poisoning
caused by contaminated cooked foods subjected to inadequate post-cooking temperature control that has allowed bacterial growth (such as reheated rice, pasta, meat or vegetable dishes, and dairy products).
Describe S. aureus infection
Causes food poisoning
usually found in cooked meats and cream products.
Describe rotavirus infection
Most common cause (though reduction in cases due to vaccine)
Transmission: person-to-person via faeco-oral route or contaminated surfaces
Winter and Spring
Symptoms include watery diarrhoea and vomiting with or without fever and abdominal pain. Vomiting usually settles within 1–3 days, and diarrhoea within 5–7 days, but can persist for 2 weeks
Describe norovirus infection
Can occur in people of all ages (immunity not long lasting)
Transmission: faecal-oral, contaminated food (oysters) or water
Symptoms begin 24-48h after infection and last for 12-60 hours
Sudden-onset nausea → projectile vomiting + watery diarrhoea
Fever, headache, abdominal pain, myalgia
Full recovery within 1-2 days
Outbreaks common in schools, hospitals, care homes, cruise ships
Describe adenovirus infection
Usually causes a RTI
Cause gastroenteritis in children
Describe campylobacter infection
One of the most common causes of traveller’s diarrhoea
May be asymptomatic (25-50%)
Diarrhoea (may be bloody), nausea, vomiting, abdominal cramps, fever
Self-limiting within 2-3 days, resolves within 1 week
Consumption of contaminated food or drink e.g. undercooked meat, unpasteurised milk untreated water
Describe E. Coli infection
E. Coli O157
Rate of infection highest in children <5yo, peak incidence 1-4
Asymptomatic OR diarrhoea (Blood), fever, abdominal cramps, vomiting
Self-limiting, resolves in 10 days
Contaminated food, water, unpasteurised milk, faecal-oral transmission - particularly in households, schools and childcare settings, and care homes; by contact with infected animals (especially cattle, sheep, goats, and other ruminants); or environmental exposure to contaminated water.
Describe salmonella infection
Majority sporadic cases
Ingestion of contaminated food e.g. red and white meat, raw eggs, milk, dairy products
Watery/bloody diarrhoea, abdominal pain, headache, nausea, vomiting, fever
Lasts 4-7 days, recover spontaneously
Describe shigella infection
Faecal-oral transmission (households, nurseries, schools), contaminated food, sexually transmitted
Commonly <5yo
Usually late summer
1-3 days following infection: diarrhoea (blood + mucus), fever, abdominal cramps ± N&V, headache, malaise
Resolves in 5-7 days
Describe yersinia infection
Rare, mostly in children
Watery diarrhoea (bloody), fever, abdominal pain (R sided in older children)
Symptoms 4-7 days after exposure, may last 2 days-6 weeks
Transmission: infected animals, faecal-oral route (raw pork and pork products)
Describe cryptosporidiosis infection
20% associated with recent foreign travel
Transmission: animals, occupational/environmental exposure, contaminated land or water
Profuse watery diarrhoea, abdominal cramps, pain, nausea, vomiting, fever, loss of appetite
Lasts 1-2 weeks
Describe entamoeba infection
Transmission: ingestion of contaminated food or water
Most cases reported in travellers to endemic areas
90% asymptomatic
Mild diarrhoea and abdominal pain
Severe: abdominal pain, blood and mucus in faeces
Describe giardia infection
Most common identified pathogen in returning travellers with prolonged diarrhoea
Transmission: faecal-oral route, contact with faeces of infected animals, contaminated food or drink, waterborne, sexually transmitted
Associated with recent foreign travel, particularly South Asia
Diarrhoea, malaise, abdominal pain, loss of appetite, flatulence, bloating, nausea, weight loss, faltering growth, malabsorption
