Viral gastroenteritis (I) Flashcards
Define viral gastroenteritis.
Acute inflammation of the lining of the stomach and intestines caused by enteropathogenic viruses
What is the typical presentation of viral gastroenteritis?
Increased frequency of defecation lasting <14 days, which may be accompanied by nausea, vomiting, anorexia, abdominal cramps and fever
What causative viruses are there for viral gastroenteritis? (3)
Norovirus > sapovirus > rotavirus (most common in infants and children)
(Hepatitis A&E, caliciviruses, astroviruses, adenoviruses, parvoviruses)
What are some bacterial causes of gastroenteritis? (3)
- Campylobacter
- E. coli
- salmonella
What are some subtypes of E. coli in relation to gastroenteritis? (5)
- enterohaemorrhagic (EHEC): Shiga-toxin producing, O157 serogroup
- enterotoxic (ETEC): cholera-like toxin
- enteroinvasive (EIEC): shigella-like illness
- enteroaggregative (EAEC)
- enteropathogenic (EPEC)
Describe the incubation period for different pathogens for viral gastroenteritis.
- hours: preformed toxins (S. aureus) and non-infectious toxins (salmonella)
- days: most viruses (exc. Hep A&E), Campylobacter, Shigella, parasites
- weeks: Hep A&E, chronic exposure to heavy metals
What type of transmission is responsible for most cases of viral gastroenteritis?
Person-to-person transmission is responsible for infection in most sporadic cases
What is viral gastroenteritis mainly caused by?
Norovirus
However, most common cause of food poisoning in UK is Campylobacter jejuni (will present after a summer BBQ/in clusters)
What are the key clinical features of viral gastroenteritis?
- diarrhoea (sudden onset)
- blood/mucus in stool - indicates invasion of intestinal/colonic mucosa
- vomiting
- nausea
- abdominal pain
- fever and malaise
- loss of appetite
- signs of dehydration (dry mucous membranes, skin turgor, capillary refill, reduced urine output, tachycardia, hypotension, weight loss)
Describe different types of stool and their causative organisms in viral gastroenteritis.
- blood/mucus in stool - indicates invasion of intestinal/colonic mucosa
- blood more common in Shiga-toxin-producing E. coli/Campylobacter/Shigella/amoebic
- rice-water stool - cholera
- watery stool - enterotoxigenic E. coli
What are the signs of dehydration in viral gastroenteritis? (7)
- dry mucous membranes
- skin turgor
- capillary refill
- reduced urine output
- tachycardia
- hypotension
- weight loss
When do symptoms set in for viral gastroenteritis caused by norovirus?
Abrupt onset, usually short-lived GI upset 24-48h after inoculation
What complication can viral gastroenteritis caused by norovirus cause and in which group?
Usually self-limiting in healthy people but can cause pre-renal AKI in frail population
How can we prevent viral gastroenteritis caused by norovirus?
Strict handwashing with soap and warm water to prevent spread
What can be seen on examination of viral gastroenteritis? (3 + 1)
- fever
- skin changes
- bloating, tenderness
Significant tenderness to palpation, guarding, rebound or point-specific tenderness should lead the clinician to consider other causes of symptomatology