Gastroenteritis Flashcards
(32 cards)
_______ illness is the leading cause of childhood death in developing countries.
Diarrheal
causes over 13% of children in Latin America to die before age 5
About how many Americans die from gastroenteritis each year?
~5,000
diarrhea costs America over $10 billion each year
What are some host factors that can contribute to gastroenteritis?
Genotype, age, personal hygiene, gastric acidity, enteric microflora, acquired immunity, innate immunity, intestinal receptors, etc
What causes over 99.9% of ingested coliform bacteria to die within 30 minutes?
The normal gastric pH of
What is the #1 most prevalent anaerobe normally in the GI tract?
Bacteroides fragilis
What is the #1 most prevalent facultative bacteria in the GI tract?
Escherichia coli
1000x more E. coli than B. fragilis
What are the three virulence factors used by microbes to attack the gut?
Toxins
Attachment
Invasiveness
Name three types of toxins.
Neurotoxins
Enterotoxins
Cytotoxins
Explain neurotoxins
Preformed toxins that cause enteric symptoms by effecting the central autonomic nervous system
Explain enterotoxins
Directly effect the intestinal mucosa to cause fluid secretion by altering the mucosal cells’ metabolic activity. Results in great electrolyte loss.
Explain cytotoxins
These actually destroy the intestinal mucosa and result in inflammatory colitis. Causes dysentery, almost always in the colon.
What microbes use neurotoxins?
Staphylococcus aureus, Bacillis cereus, Clostridium botulinum
What microbes use enterotoxins?
Vibrio cholerae, Escherichia coli, Salmonella spp., Clostridium perfringens, Shigella dysenteriae, Bacillus cereus
What microbes use cytotoxins? (sicknesses found in colon)
Shigella dysenteriae, Clostridium difficile, Clostridium perfringens, Staph aureus, Campylobacter jejuni
Which microbes use attachment virulence factors to destroy cells’ ability to participate in normal secretion and absorption?
Escherichia coli, Giardia lamblia, Cryptosporidium, Isospora
Which microbes invade the epithelial cells to destroy the mucosa? (mostly in the colon causing dysentery)
Shigella spp., E. coli, Salmonella typhi, Salmonella cholerasuis, Vibrio spp., Yersinia enterocolitica
84% of food-borne illnesses in the US is caused by ________ and _______.
bacteria, viruses
What are the two most common microbes to cause food-borne illness?
Campylobacter jejuni and Salmonella spp.
mostly found in poultry
What virulence factor is the reason for almost immediate diarrhea?
preformed toxins (neurotoxins)
Why does Salmonella take longer to induce gastroenteritis?
Salmonella doesn’t have preformed toxins, so it usually takes about a day for symptoms to show
In what population is Shigella most commonly seen? And what is a unique sign of a Shigella infection?
Popular in large groups of kids (daycares, schools, etc)
Sign of pus in the diarrhea
What microbe would you most definitely see in raw/undercooked seafood?
Vibrio parahaemolyticus
Instead of a spore, what does Vibrio cholerae form?
A copiopod
If a patient is experiencing diarrhea and kidney dysfunction, what might be the culprit?
Shigella toxin-producing E. coli (STEC)
