Curved Gram-Negative Bacilli and Oxidase-Positive Fermenters Flashcards
What is the habitat of the Vibrio genera?
Fresh, marine, and salt water
What are the general characteristics of Vibrio?
Catalase positive, oxidase positive, glucose fermenters, growth on MacConkey
Where is Vibrio parahaemolyticus an endemic
Japan
How is Vibrio parahaemolyticus transmitted?
From ingesting raw or undercooked seafood, specifically shellfish and fish
What is the gram stain of Vibrio?
Curved, gram negative bacillus.
What is the colony morphology of Vibrio? What agars does it grow well on?
Grows well on BAP, MacConkey, and Chocolate agars; Large colonies, greenish hue
What is the selective, differential media for Vibrio?
Thiosulfate-citrate-bile-sucrose (TCBS) agar
What is the appropriate primary isolation media for Vibrio?
Cary-Blair media for specimens
What are the symptoms of Vibrio parahaemolyticus most similar to? Is it self-clearing
Shigella dysentery; Yes
What does Vibrio cholera cause?
Cholera
How many cholera pandemics has the word seen since 1817?
7 !!!
In which regions is Vibrio cholera an endemic?
India, Bangladesh, Africa, and Philipines
What is the mode of transmission for Vibrio cholera?
Contaminated food or water
What is the hallmark symptom of Vibrio cholera?
āRice waterā stool
What is responsible for the massive, watery diarrhea characteristic of Vibrio cholera?
The CT-protein complex (Cholera toxin)
What is the string test? Which organism is it used to ID?
A test to ID Vibrio cholera, using Na-deoxycholate (bile) to lyse bacteria and release DNA that can be pulled up like a string
Which species of Vibrio requires salt for growth?
Vibrio parahemolyticus
What is the habitat of Aeromonas?
Fresh water and sea water (sink taps, drainpipes, DI H2O taps); Infects fish and reptiles
What is the gram stain of Aeromonas hydrophila?
Small GNB
What is the colony morphology of Aeromonas hydrophila?
Beta hemolysis on BAP
What is one of the distinguishing factors of Aeromonas hydrophilis?
It is DNase positive
What is the habitat of Pleisomonas shigelloides?
Surface H2O of tropical and subtropical areas; Reptiles and amphibians
What is the mode of transmission for Pleisomonas shigelloides?
Hand to mouth; eating contaminated shellfish
Does Pleisomonas shigelloides produce an enterotoxin?
Yes
Is Pleisomonas shigelloides rarely or commonly recovered?
Rarely
What is the colony morphology of Pleisomonas shigelloides?
Non hemolytic on BAP
What is the gram stain of Pleisomonas shigelloides?
Small GNBs
What is the habitat of Campylobacter?
Worldwide, seen in domestic animals (normal flora in chicken and turkeys)
What is the mode of transmission for Campylobacter?
Ingestion of raw milk, uncooked poultry, or contaminated water
What are the special growth requirements for Campylobacter?
41-42C temp and special air requirements (85% N2, 10% CO2, and 5% O2)
What is the selective recovery media for Campylobacter?
Campy CVA agar
What is the hallmark symptom of Campylobacter?
Diarrhea with RBCs and WBCs
What is the gram stain of Campylobacter jejuni?
Gull shaped, cuved or āSā shaped GNBs
What is the colony morphology of Campylobacter?
Flat, moist, spready
What is the distinguishing biochemical test for Campylobacter jejuni?
Hippurate hydrolysis positive
What is the habitat of Helicobacter pylori?
The epithelial cells in stomach, can withstand the pH of the stomach
What is the mode of transmission of Helicobacter pylori?
Contact with contaminated saliva and fresh ground water
What disease does Helicobacter pylori cause?
Peptic ulcers, increases risk of cancer
How do you recover Helicobacter pylori?
Brucella agar
What is the colony morphology of Helicobacter pylori?
Small, pinpoint colonies
What is the gram stain for Helicobacter pylori?
Spiral shaped GNB
What is the distinguishing biochemical test for Helicobacter pylori?
Urease positive; rapid urea positive tests can be done (balloon test and card test)
What does a stool antigen test tell you about a patient suspected to have Helicobacter pylori?
Whether they have a current infection
What does a serum antibody test tell you about a patient suspected to have Helicobacter pylori?
Whether they have a current or past infection (cannot differentiate)