Flashcards in Gastroenteritis and Food Poisoning Deck (138):
What condition causes GI symptoms, diarrhoea, vomiting, abdominal pain and relates to invasion of tissue +/- toxin production?
What is the commonest cause of food poisoning?
What cause of food poisoning is rare, but can lead to morbidity and outbreaks?
E coli O157
What two organisms have a short incubation period of 1-6 hours?
Staph aureus and Bacillus cereus
What two organisms have a medium incubation period of 12-48 hours and there is invasion/toxin in gut which can often cause blood diarrhoea?
What 2 organisms have a long incubation period of 2-14 days and can cause bloody diarrhoea?
Campylobacter and E coli O157
How long does it take for labarotory confirmation of bacteria?
48 hours for culture result
What two food products can campylobacter come from?
Which organism rarely causes outbreaks, occurs in small numbers and results in pain, blood and a fever?
What is the treatment for campylobacter?
What 3 food products can salmonella enteritidis come from?
Poultry, meat, raw egg
Where is salmonella occuring?
In animal gut
What is the treatment for salmonella enteritidis, which causes diarrhoea, vomiting, blood and fever?
What are the three most common groups of salmonellae?
B, C and D
What king of diarrhoea does E coli O157 cause?
Is the infectious dose low or high for E coli O157?
What two food products can E coli O157 come from?
Beef and raw milk/water
How can E coli O157 be transmitted?
Person to person
What toxin does E coli O157 produce?
What organism can cause bloody diarrhoea nad haemorrhagic colitis?
E coli O157 VTEC
What syndrome can Haemolytic Uraemic Syndrome (HUS)?
E coli O157
`What three things does verotoxin do?
1. Binds to receptors found on renal cells, RBC and others
2. Inhibits protein synthesis
3. Causes cell death
What is this a presentation of: abdominal pain, fever, pallor, petechiae, blood diarrhoea and oliguria?
What patients are commonly infected by HUS?
Under 16 years old
In HUS what are the white cells like, platelets, Hb, LDH?
LDH > 1.5 x normal
How is HUS investigated?
Send stool culture samples for all bloody diarrhoea samples
Other than U&S, FBC, film, LFT, clotting what else would you send for?
What are three complications of HUS?
1. Acute renal failure
3. Haemolytic anaemia
What 3 drug types are NOT given in HUS?
2. Anti-motility agents
What kind of diagnosis are these factors involved in: selective culture, sorbitol non fermenter, E coli isolated, check for O157 antigen?
What infection is associated with contacting farm animals and private drinking water?
E coli O157
What two things must you notify the Health Protection Unit on?
Haemolytic Uraemic Syndrome or O157
What is the likely cause of blood diarrhoea in children and elderly?
E coli O157
What virus is the commonest cause in kids
How is rotavirus transmitted?
Person-person and faecal oral
What is diarrhoea like in rotavirus?
Not bloody, mild and watery
Along with diarrhoea, what 2 other symptoms occur in rotavirus?
Vomiting and fever first
What is the infectious dose like in rota virus?
How is rota virus diagnosed?
PCR diagnosis on faeces
What is management for rotavirus?
What is the rota virus vaccine like?
Oral and live attenuated
What is the 'Winter Vomiting Disease'?
How is norovirus spread?
Faecal-oral/droplet routes spread, person to person or on contaminated food/water
What is the infectious dose like for norovirus?
What is diarrhoea anad vomiting like in norovirus?
Explosive and sudden
What is the incubation for norovirus like?
In what 2 ways is norovirus diagnosed?
1. PCR on stool takes 6 hours
2. PCR on vomit using red Copan viral swabs
What is the management for norovirus?
What infection is a side effect on antibiotic treatment?
What two toxins does Cl difficile produce?
Enterotoxin and cytotoxin
Does CI difficile produce spores?
Where can CI difficile cause symptoms?
In the colon
What infection is related to "mild, bloody pseudomembranous colitis"?
What patients are most likely affected with C diff?
Elderly females >65
What 4 factors cause a high index of suspicion for C difficile?
1. Recent antibiotics
4. Use of stomach acid suppressants like PPIs
What is the diagnosing test for C diff?
Toxin/antigen sensitive screening test: 24 hour turnaround
On sigmoidoscopy of C diff patient, what is seen?
What two types of C diff are virulent strains producing 20x more toxin and lead to aggressive disease and death?
What is the term for inflammation of stomach or intestines - it inhibits nutrient absorption and excessive H2O and electrolyte loss?
What are 3 preformed organisms that cause food poisoning?
1. Staph auresu
2. Clostridium perfringens
3. Bacillus cereus
What 2 organisms cause in vivo production of toxin related food posioning?
2. Enterotoxigenic E.coli
What are the three clinical syndromes of acute enteritis?
2. Diarrhoea and vomiting
3. Abdominal pain
What are the three clinical syndromes of enteric fever like illness?
What 4 organisms can cause bloody diarrhoea and usually indicate colonic inflammation?
3. E coli
What is a rare, but important complication of Campylobacter?
What can severe cases of campylobacter be treated with?
Clarithromycin or azithromycin
What condition involves tingling of the feet, leading to progressive paralysis of the legs, arms and rest of body?
What type of fever is typhoid?
What type of enteric fever is imported from India, SE Asia, Far East, Middle East and Africa?
What two ways is typhoid transmitted?
Food and water
What are the 3 features of presentation of typhoid?
1. Asymptomatic. mild
What is key to diagnosis of typhoid, but what can also be done to help?
Stool and urine culture
What 4 antibiotics are used to treat Tyhpoid?
1. Chloramphenicol and Ciprofloxacin
2. Ceftriaxone or azithromycin
What two infections require an in depth travel history?
What investigation would be done for Salmonella, Campylobacter and Shigella?
What two infections require toxin testing?
What organism would you do a blood culture for?
What is creatinine like in C.diff?
>1.5 x baseline
What four factors are severity markers of C.diff?
1. Pseuodemembranous colitis
2. Toxic megacolon
4. Colonic dilatation >6cm
Give 4 complications of bacterial enteritis intestinal?
1. Severe dehydration and renal failure
2. Acute colitis, toxic dilatation
3. Post infective irritable bowel (very common)
4. Transient secondary lactase intolerance
What are septicaemia, meningitis, aortitis, ostyeomyelitis, endocarditis, reactive arthritis, meningism, Guillian Barre Syndrome, haemolytic uraemic syndome all complications of?
Bacterial enteritis extra-intestinal
Name two antimotility agents?
Opiates and loperamide
Name tow anti-secretory agents?
Chlorpromazine, bismuth subsalycilate
Name two absorbents?
What is an anaerobic gram-positive spore forming bacillus?
What are four antibiotics that are risk factors for C diff?
4. Broad spectrum penicillins
What are two medications that can be risk factors for C diff?
2. H2 receptor antagonists
What are the 4 C. dff causing antibiotics?
3. Ciprofloxacin (quinolines)
4. Clarithromycin (macrolides)
For pseudomembranous colitis, what drugs should be stopped and what antibiotic should be given?
Stop opiates, PPIs and anti-perstaltic drugs
Give oral vancomycin or metranidazole for non-severe cases
What drug is used for a relapse of c diff?
What are 3 travel related diarrhoea causes?
What is a protozoal infection spread by faeco-oral route or by an ill or asymptomatic carrier?
What areas is amoebiasis com mon in?
Areas of poor sanitation
What is the diarrhoea like in amoebiasis?
Acute and bloody
How is diagnosis ofintestinal amoebiasis made?
By examination of hot stool for ova and cysts (stool M & C)
What is the treatment for amoebiasis?
Metronidazole. Remove from lumen by using diloxanide furate or paromomycin
What is the diarrhoea like in giardiasis?
Explosive, protracted and foul smelling
What infection is protozoan Giardia lambia trophozoites colonising the small bowel mucosa to produce diarrhoea?
How is Giardiasis spread?
Spread by cysts found in normal drinkng water
How is giardiasis diagnosed?
Examine stools for ova and cysts but more accurately by duodenal aspiration.
How is giardiasis treated?
What is one of the main causes of infectious diarrhoea in many parts of the world and is an important cause of travel related diarrhoea?
How is cryptosporidiosis transmitted?
Water, food, animal contact, highly infectious and resilient
What patient types usually get cryptosporidiosis (C.parvum)?
West African Children
How is cryptosporidiosis diagnosed?
By duodenal aspirate/stool
How is cryptosporidiosis treated?
How is diagnosis of extra-intestinal ameobiasis made?
Name two arboviruses?
What is the definition of acute tranveller's diarrhoea?
3 loose stools in 24 hours
What typically causes acute traveller's diarrhoea?
Enterotoxigenic E. coli
Other than E.coli, what three other causes of acute traveller's diarrhoea are there?
Campylobacter, Salmonella and Shigella
What is commonly caught on Cruise ships?
Noravirus or rotavirus
What infection is often associated with outbreaks in refugee camps?
What two investigations are done for acute traveller's diarrhoea?
1. Stool culture
2. Stool wet prep on recently passed stool for amoebic trophozoites
What is the treatment for Acute traveller's diarrhoea?
Supportive - fluid rehydration
In travelling patients, ciprofloxaacin single dose can stop worsening
What is most common from travellers returning from India subcontinent or SE Asia?
Typhoid or paratyphoid fever (enteric fever)
Where is Salmonella typhi usually isolated from?
Blood, stool or urine
How is Salmonella typhi treated?
What three things can be a cause of fever and pre-hepatic jaundice?
Malaria, HUS (E.coli O157/Shigella), sickle cell crisis
What does leptosirosis cause?
Weils disease (icteric, haemorrhagic and renal failure)
What is a post-hepatic cause of fever and jaundice?
Ascending cholangitis and helminths
How is malaria investigated?
Blood film and rapid antigen
What is this: incubation period 9-20 weeks, fever, cough, aching abdominal pain, hepatomegaly, sometimes a history of GI upset and usually male?
Amoebic liver abscess
How is amoebic liver abscess investigated?
CXR (raised right hemidiaphragm)
Abnormal LFTs, US/CT, serology,
What is the management for amoebic liver abscess?
Metronidazole and paramomycin/diloxanide to clear gut lumen of parasites
What are Helminth infections - parasites - often diagnosd by?
The adult worm passed or eggs in stool
What are two types of nematodes (round worms)?
Tissue roundworms (filariasis)
What are trematodes?
What are cestodes?
What is the most common helminthic infection in the world?
What is the life-cycle of a helminth infection?
Egg ingested and hatches in small intestine. Invades gut wall into venous system and via liver and heart reaches lungs. Breaks into alveoli and ascends tracheobronchial tree then becomes swallowed. In the gut develops into adult worm where they start to produce eggs.
Name a trematode (fluke) and where can you get it from?
Schistosomiasis - fresh water exposure
What can adult worms located in portal venules lead to?
Hepatomegaly, liver fibrosis and portal hypertension
How can cestodes such as tapeworms Taenia solium or Saginatum, be aquired?
By eating undercooked meat containing infectious larval cysts
What can Taenia solium eggs cause?
Cysticercosis - tissue cysts muscle and brain
What protozoa is involved in Chagas disease?
How is Chagas disease transmitted?
By the kissing bug