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18 Cards in this Set
- Front
- Back
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Culture results: Flat, yellow colonies grew on TCBS (thiosulfate-citrate-bile salts-sucrose) agar
The isolate was identified as _______ _______ 01 bio type el tor |
Culture results: Flat, yellow colonies grew on TCBS (thiosulfate-citrate-bile salts-sucrose) agar
The isolate was identified as Vibrio cholerae 01 bio type el tor |
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Vibrio cholerae
Gram-negative _(shape)_ rods Free-living in fresh water; causes disease only in humans Many serotypes, but only 2 serotypes cause cholera 01 and 0139 produce cholera toxin Toxin is encoded on p_____ genome Transmitted in contaminated food and water Associated with epidemics and pandemics |
Vibrio cholerae
Gram-negative curved rods Free-living in fresh water; causes disease only in humans Many serotypes, but only 2 serotypes cause cholera 01 and 0139 produce cholera toxin Toxin is encoded on phage genome Transmitted in contaminated food and water Associated with epidemics and pandemics |
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Stool description assoc with cholera
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Rice water stool
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Cholera toxin activates the a________ c_______ enzyme in cells of the intestinal mucosa leading to increased levels of intracellular ____, and the secretion of H20, Na+, K+, Cl-, and HCO3- into the lumen of the small intestine
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Cholera toxin activates the adenylate cyclase enzyme in cells of the intestinal mucosa leading to increased levels of intracellular cAMP, and the secretion of H20, Na+, K+, Cl-, and HCO3- into the lumen of the small intestine
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Diagnosis and Treatment, of Cholera
Diagnosis Clinical manifestation, history ____ water stools Growth on ____ agar Treatment Can cause death in hours in severe, untreated cases Oral _________ Therapy *** Antibiotics can shorten course Several can be used |
Diagnosis and Treatment, of Cholera
Diagnosis Clinical manifestation, history Rice water stools Growth on TCBS agar Treatment Can cause death in hours in severe, untreated cases Oral Rehydration Therapy*** Antibiotics can shorten course Several can be used |
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Prevention of Cholera
Prevention: Vaccine 2 vaccines available in other countries; provide brief and incomplete immunity __ vaccine is licensed in the US When traveling in endemic areas “if can’t boil it, peel it or cook it, don’t eat it!” Drink only _______ beverages Do not eat raw foods Do not add ___ to drinks |
Prevention of Cholera
Prevention: Vaccine 2 vaccines available in other countries; provide brief and incomplete immunity No vaccine is licensed in the US When traveling in endemic areas “if can’t boil it, peel it or cook it, don’t eat it!” Drink only bottled beverages Do not eat raw foods Do not add ice to drinks |
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Other Vibrio sp
V. para__________; V. vul_______ Found in estuarine and marine environments Cause GI disease following ingestion of poorly cooked shellfish or raw fish Causes aggressive soft tissue infections if wound is exposed to contaminated seawater Many cases of wound infections occurred following hurricane Katrina |
Other Vibrio sp
V. parahaemolyticus; V. vulnificus Found in estuarine and marine environments Cause GI disease following ingestion of poorly cooked shellfish or raw fish Causes aggressive soft tissue infections if wound is exposed to contaminated seawater Many cases of wound infections occurred following hurricane Katrina |
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Question- what is the most common cause of travelers diarrhea in people returning to the US?
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E. Coli
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Common Causes of Traveler's Diarrhea
Bacteria Enterotoxigenic E. coli Other E. coli types (e.g., enteroaggregative E. coli) Cam__________ Salmonella (non-typhoid) S_______ Aero______ Vibrio (non-cholera) Parasites ________ lamblia ________ histolytica ________ cayetanensis ____________ parvum Viruses Rotavirus Noroviruses |
Common Causes of Traveler's Diarrhea
Bacteria Enterotoxigenic E. coli Other E. coli types (e.g., enteroaggregative E. coli) Campylobacter Salmonella (non-typhoid) Shigella Aeromonas Vibrio (non-cholera) Parasites Giardia lamblia Entamoeba histolytica Cyclospora cayetanensis Cryptosporidium parvum Viruses Rotavirus Noroviruses |
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E. Coli
Family Enterobacteriaceae Gram-negative enteric rods Other members of family: S_________, S________, K_________, E_________, Y________, P________, M________ Family causes diseases of CNS, RT, GIT, UT, spticemia |
E. Coli
Family Enterobacteriaceae Gram-negative enteric rods Other members of family: Salmonella, Shigella, Klebsiella, Enterobacter, Yersinia, Proteus, Morganella Family causes diseases of CNS, RT, GIT, UT, spticemia |
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Virulence factors of E. coli
C_______ LPS A_______ E________ |
Virulence factors of E. coli
Capsule LPS Adhesins Exotoxins |
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Strains of E. coli that cause GI disease are subdivided into 5 groups
ETEC- ___________ E. coli EPEC- ___________ E. coli EHEC- _____________ E. coli EIEC- ____________ E. coli EAEC- _____________ E. coli |
Strains of E. coli that cause GI disease are subdivided into 5 groups
ETEC- enterotoxigenic E. coli EPEC- enteropathogenic E. coli EHEC- enterohemorrhagic E. coli EIEC- enteroinvasive E. coli EAEC- enteroaggregative E. coli |
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Enterotoxigenic E. coli
Most important bacterial cause of _________ in children in developing countries Most common cause of _________ diarrhea 800,000 cases/yr in travelers from US Spread by fecal contamination of food or water; not person-to-person Diarrhea results from action of bacterial _________ |
Enterotoxigenic E. coli
Most important bacterial cause of diarrhea in children in developing countries Most common cause of traveler’s diarrhea 800,000 cases/yr in travelers from US Spread by fecal contamination of food or water; not person-to-person Diarrhea results from action of bacterial exotoxins |
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Pathogenesis of ETIC
Ingested in fecal-contaminated food or water Bacteria adhere via ____ to specific receptors on epithelial cells of small intestine Two plasmid-associated enterotoxins are produced 1) ________________ 2) ________________ Mechanism of action is similar to cholera toxin -LT leads to increased c___ -ST leads to increased c___ |
Pathogenesis of ETIC
Ingested in fecal-contaminated food or water Bacteria adhere via pili to specific receptors on epithelial cells of small intestine Two plasmid-associated enterotoxins are produced 1) Heat labile (LT) 2) Heat stable (ST) Mechanism of action is similar to cholera toxin -LT leads to increased cAMP -ST leads to increased cGMP |
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Diagnosis of ETEC
Isolate organism from stool -Use _________ agar --See notes pages ___________ for detection of LT and ST from cultured organisms |
Diagnosis of ETEC
Isolate organism from stool -Use MacConkey agar --See notes pages Immunoassays for detection of LT and ST from cultured organisms |
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MacConkey
Lactose-fermenting bacteria appear _______ ______, while non-lactose-fermenting bacteria appear __________ |
Lactose-fermenting bacteria appear bright pink, while
non-lactose-fermenting bacteria appear colorless |
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Treatment of ETEC
ORT For mild cases, nonprescription anti-motility medications: b______ s___________ and l________. The use of an antibiotic can reduce the duration of illness from days to hours. Antibiotic may be required for or moderate to severe diarrhea ____________________________ (Bactrim) Ciprofloxacin (Cipro) Norfloxacin (Noroxin) Ofloxacin (Floxin) ____________ (Vibramycin) |
Treatment of ETEC
ORT For mild cases, nonprescription anti-motility medications: bismuth subsalicylate and loperamide. The use of an antibiotic can reduce the duration of illness from days to hours. Antibiotic may be required for or moderate to severe diarrhea Trimethoprim-sulfamethoxazole (Bactrim) Ciprofloxacin (Cipro) Norfloxacin (Noroxin) Ofloxacin (Floxin) ___________ (Vibramycin) |
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Enteropathogenic E. coli
Another E coli strain causing infection in the _____ intestine Causes non-bloody, watery diarrhea, especially in _______ in developing countries a leading cause of ________ diarrhea**** Not toxin-mediated Cause “attaching and effacing lesions” in gut that interfere with normal cellular function |
Enteropathogenic E. coli
Another E coli strain causing infection in the small intestine Causes non-bloody, watery diarrhea, especially in infants in developing countries a leading cause of infantile diarrhea**** Not toxin-mediated Cause “attaching and effacing lesions” in gut that interfere with normal cellular function |
