Viral gastroenteritis

Question 1

Define gastroenteritis

Answer 1

Transient disorder due to enteric infection with viruses, bacteria or parasites

Question 2

Define food poisoning

Answer 2

illness caused by the consumption of food or water contaminated with bacteria and/or their toxins, or viruses, parasites, or chemicals

Question 3

Define dysentery

Answer 3

acute infectious gastroenteritis characterised by diarrhoea with blood and mucus

Question 4

Define outbreak

Answer 4

Two or more cases associated in time and place

Question 5

Define traveller’s diarrhoea

Answer 5

developing diarrhoea at a destination abroad with at least one additional symptom (abdominal cramps, tenesmus, nausea, vomiting, fever, faecal urgency), involves travel from LMICs

Question 6

What are the causes of gastroenteritis

Answer 6

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

Question 7

What are the symptoms and signs of gastroenteritis

Answer 7

Diarrhoea (sudden onset, ± blood, mucous, faecal urgency)
Nausea and vomiting
Fever
Abdo pain and cramps
General malaise
Headache, myalgia, bloating, flatulence, weight loss, malabsorption

Question 8

Define acute diarrhoea

Answer 8

3 or more episodes of liquid or semi-liquid stool in a 24h period, <14 days

Question 9

What investigations should be done for gastroenteritis

Answer 9

Bedside: stool culture, ova and parasite testing
Bloods: FBC, U&Es, glucose, blood cultures

Question 10

What necessitates hospital admission for gastroenteritis

Answer 10

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

Question 11

What is the management for gastroenteritis

Answer 11

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

Question 12

What advice should be given regarding preventing transmission of gastroenteritis

Answer 12

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)

Question 13

What are the complications of gastroenteritis

Answer 13

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)

Question 14

What is the prognosis for gastroenteritis

Answer 14

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.

Question 15

Describe clostridium perfringens infection

Answer 15

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

Question 16

Describe bacillus cereus infection

Answer 16

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).

Question 17

Describe S. aureus infection

Answer 17

Causes food poisoning
usually found in cooked meats and cream products.

Question 18

Describe rotavirus infection

Answer 18

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

Question 19

Describe norovirus infection

Answer 19

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

Question 20

Describe adenovirus infection

Answer 20

Usually causes a RTI
Cause gastroenteritis in children

Question 21

Describe campylobacter infection

Answer 21

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

Question 22

Describe E. Coli infection

Answer 22

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.

Question 23

Describe salmonella infection

Answer 23

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

Question 24

Describe shigella infection

Answer 24

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

Question 25

Describe yersinia infection

Answer 25

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)

Question 26

Describe cryptosporidiosis infection

Answer 26

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

Question 27

Describe entamoeba infection

Answer 27

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

Question 28

Describe giardia infection

Answer 28

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