Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
23 Cards in this Set
- Front
- Back
|
High risk populations for GI infections
|
Young, old.
Lack of antibodies |
|
|
What is the route of exposure to GI bugs
|
Fecal - oral spread.
|
|
|
Local GI factors that prevent bacterial infection
|
-Stomach acid (may be overcome by H2 channel blockers)
-Intestinal motility -Normal microbiota |
|
|
Systemic immune mechanisms vs. GI bugs
|
-Local antibodies - secretory IgA
-Systemic antibodies -PMNs, macrophages for organisms that penetrate the mucosa |
|
|
Characteristics of an upper bowel infection
|
Secretory
|
|
|
Characteristics of an lower bowel infection
|
Inflammation
|
|
|
Components of information needed for diagnosis of GI bug
|
-Where have you eaten/traveled/animals?
-Nature of the diarrhea -Examine the patient (dehydrated? crampy pain? acutely/cronically ill? -Stool sample -Blood cultures -Endoscopy, biopsy |
|
|
Information gathered from a stool sample
|
-Gross view
-Microscopic view -Culture (bacteria) -Antigen detection (viruses) -Presence of parasites, ova |
|
|
Mechanisms of food poisoning
|
-Non-microbial (shrooms, shellfish, heavy metals)
-Microbial (preformed toxins from bugs) |
|
|
Bugs that cause food poisoning
|
-S. aureus (potatoes at a picnic)
-B. cereus (fried rice) -C. difficile |
|
|
S. aureus mechanism of food poisoning
|
-In vitro toxin production at warm temperatures
-Prevention: refrigeration, hand washing |
|
|
B. cereus mechanism of food poisoning
|
-Germination of spores that contaminate food from air
-Heat stable toxins produced by bugs @ warm temperatures |
|
|
Symptoms/signs of food poisoning
|
-Short incubation period
-EXPLOSIVE onsiet -Nausea/vomiting -Toxic; rarely dehydrated |
|
|
Viruses causing viral gastroenteritis
|
Noroviruses (adults, kids)
Rotaviruses (kids, 6-24 mo) |
|
|
Norovirus epidemiology
|
-Short incubation time
-High attack rate -Able to survive in envt. (naked) -Person:person, fecal:oral spread -Prevented by well-cooked food |
|
|
Norovirus symptoms and signs
|
-Small bowel involvement
-Nausea and vomiting - +/- fever -Dehydration in kids |
|
|
Norovirus dx.
|
-Clinical
-PCR for confirmation |
|
|
Norovirus tx.
|
-Supportive
|
|
|
Rotavirus characteristics
|
Naked
dsRNA |
|
|
Rotavirus epidemiology
|
-Short incubation; high attack rate
-Fecal-oral spread -Disease of the INFANTS!!! -Immunity by age 4 |
|
|
Rotavirus diagnosis
|
-Clinical
-EIA on stool |
|
|
Treatment for rotavirus
|
-Supportive
|
|
|
Rotavirus prevention
|
-Human live attenuated vaccine (monovalent)
-Human/bovine live recombinant vaccine (pentavalent) |
