Gastroenteritis Flashcards
What is gastroenteritis?
Inflammation of the stomach or intestines
What does gastroenteritis do?
inhibits nutrient absorption and excessive H2O and electrolyte loss
What are the 4 causes of gastroenteritis
Bacterial
Viral
Parasitic
Poisoning by microbial toxins
What makes you feel worse - bacterial or viral?
Bacterial
What is the most common cause of gastroenteritis
Infection mostly caused by a virus, bacteria or parasite
Why is there a lower incidence of Gastroenteritis in Dundee than there is in London
The number of parasites increases with the population of a city
What are the main common presentations of gastroenteritis
Fever
Abdo pain
Diarrhoea
Sometime blood PR
Why is there only sometimes blood PR
Certain pathogens cause blood- some are more likely than others
What is an example of a pathogen likely to cause blood
Campylobacter
When is the onset for toxin mediated food poisoning
1-6 hours after exposure
Why is foodborne illness a rapidly emerging crisis in industrialised countries
Poor sanitation and hygiene Change in eating habits Importation of food Increase in day care centre attendance Increase in elderly care institutes Increased travel Pets carry many pathogens
What do poultry and eggs carry? How could we get this?
Campylobacter - if we do not cook the meat well enough
What are some non-infectious diarrhoea examples
GI bleed Ischaemic gut Diverticulitis Endocirne disorders Numerous drugs Fish toxins Withdrawl
How do we approach any clinical infection syndrome
Find what the key clinical symptoms and signs are that suggest infection
Differential diagnosis
Severity of infection
Site and microbiological diagnosis and investigations
Antibiotic and supportive management
Infection control
Public health
How does the norovirus spread
As a spray in vomit
Faecal/ oral
How long does it take for the norovirus to resolve
24-48 hours
What are the common symptoms of norovirus
Abrupt nausea, vomiting, diarrhoea, cramps, myalgias
Who is most likely to get the norovirus
Older children and adults - not children
What are the 3 common presentations of food poisoning
Acute enteritis: fever, D&V, abdo pain
Acute colitis: fever, pain, bloody diarrhoea
Enteric fever like illness: fever, rigors, pain, but little diarrhoea by the time the present
What does blood diarrhoea usually indicate
Infection
IBD
Malignancy
Iscahemia
What is a complication of campylobacter
Guillain Barre
How long does Campylobacter affect us for
5-14 days
What do indentations on an AXR indicate
Inflammation
What are the common symptoms of enteric fever like illness
Give an example of enteric fever
Fever
Systemically unwell
Abdo pain
Constipation but possibly short history if diarrhoea
Typhoid is an example
What is typhoid?
A type of salmonella
In what countries is typhoid present?
India SE Asia Far East, Middle East Africa Central America South America
How is typhoid carried?
In food and water
What are the symptoms of typhoidW
Usually asymptomatic,
mild,
bacteriaemia,
enterocolitis
Define enterocolitis
inflammation of the small intestine and the colon
How can we diagnose typhoid
Blood, Stool and urine cultures
How can we treat typhoid?
Chloramphenicol and ciprofloxacin
What antibiotics are used in India, China or Middle east and why are they different?
Ceftriaxone or axithromycin
Resistance - the antibiotics were over used there
How can we prevent Typhoid?
How effective is this method?
VI or oral vaccine
70% effective
What does the thyphoid vaccine not protect against?
Paratyphoid
What are the 3 main investigations for determining the pathogen of gastroenteritis
Stool microscopy
Stool culture
Stool toxin
What investigation should be done for salmonella, campylobacter and shigella
Stool culture
What investigation should be done for a history of travel for giardia, amoeba etc
Stool microscopy
What investigation should be done for C difficile, cytotoxin for E coli 0157
Stool toxin
What would PCR detect?
Norovirus
How can you assess the severity of gastroenteritis?
Underlying medical condition Presence or absence of fever Rigors Shock (hypotension / tachycardia) Blood in stools Abdo pain Number of stools in 24 hours Colonic dilation WCC, U&Es
What determines how severe CDI is?
Suspicion of psudomembranous colitis (PMC) or toxic megacolon or ileus or colonic dilation in CT / AXR >6cm
WCC >15cells / mm3
Creatinine >1.5 x baseline
Name 4 complications of Bacterial Enteritis within the small bowel
Severe dehydration and renal failure
Acute colitis, toxic dilation
Post infective irritable bowel
Transient secondary lactase intolerance
Name 6 complications of bacterial enteritis outside of the bowel
Septicaemia Metastatic infection: meingitis , aortitis, endocarditis Reactive arthritis Guillian Barre syndrome Haemolytic uraemic syndrome
What supportive treatment is given>
Oral rehydration IV fluids (saline!!)
What are specific treatments which can be used
Anti-spasmodics
Anti-motility
Antibiotics - only in specific regions
What is bad about long term antimotility drugs
They stop the normal peristaltic movements and prevent the body naturally clearing toxins
What 3 drugs are used as antidiarrhoeal agents
Antimotility agents
Antisecretory agents
Absorbents
Name 4 indications for antibiotic treatment
Enteric fever (tyohoid)
Shigellosis
Cholea
C difficile diarrhoea
What are the 3 main aims of antibiotic treatment
To prevent and treat invasive disease especially in immunocompromised patients
To reduce the severity and duration of symptoms
To eradicate faecal excretion in order to reduce environmental contamination and to limit the spread of infection to the community
What type of organism is clostridium difficile
Anaerobic, gram positive spore forming bacillus
What is the major cause of diarrhoea and colitis in patients exposed to antibiotics
C diff
How can we minimise the spread of CDI
Patients positive in a private room where possible
Full barrier praucations
Soap and water and not gel!
How do we treat c diff
Treeat according tot he severity
Reduce the acute complitions
Reduce the likelihood of recurrence
Treat recurrence
What are 3 pathogens found in travel related diarrhoea
Amoebiasis
Giardiasis
Cryptosporidiosis
What is the most common cause of traveller’s diarrhoea
ETEC
How long does traveller’s diarrhoea last
Around 4 days
What is amoebiasis
A protozoal infection which is spread by faeco-oral route or by an ill or asymptomatic carrier
Where is there a high prevelance of amoebiasis
In areas of poor sanitation
What is Giardiasis
Protozoon Giardia lambia trophoxoites colonises the small bowel mucosa to produce diarrhoea and malabstoptions
How is Giardiasis spread
Cysts found in the normal drinking water
How can we treat giardiasis
Metronidazole
