P. aeruginosa - H. pylori Flashcards
This is a Gram (+) curved rod, aerobic, and mobile. It’s oxidase positive. Some strains with capsule appear mucoid. It has polar flagella.
P. aeruginosa
How is p. aeruginosa ID’d?
lactose non-fermenter, grape-like odor, green color on MA, non-fastidious (4-42 degrees, tap water)
P. aeruginosa is the #1 cause of infection in which patients?
cystic fibrosis patients
P. aeruginosa is non normal flora, but ubiquitous where?
in nature and moist hospital environments
note: mostly nosocomial
P. aeruginosa is the leading cause of ____-associated pneumonia.
ventilator
note: tracheobronchitis to necrotizing bronchopneumonia can be seen
In regards to bacteremia caused by P. aeruginosa, it is similar to other Gram (-) bacteria but the patient may develop ______ ______, which are small or large painful maculopapular lesions that start out pink but progress to purple/black necrotic lesions
Ecthyma gangrenosum (painful, unlike B. anthracis)
P. aeruginosa can cause pyoderma where?
face
P. aeruginosa can also cause eye infections - ____ ___ under soft contact lens can lead to vision loss
corneal ulcer
P. aeruginosa can cause OTITIS EXTERNA. Describe the symptoms.
mild to severe destruction of cranial bones!; itching, pain, mucopurulent discharge, lumen narrowed; “swimmers ear”
P. aeruginosa can cause endocarditis, commonly in what individuals? What part of the heart is affected?
IV drug users; tricuspid wall (unique endocarditis)
P. aeruginosa causes a ton of virulence factors that cause chronic lung infections due its ability to do what?
tightly adhere to mucus and damper host immune system
This is a curved, Gram (-) rod that is highly motile. It is oxidase positive and has darting motility. It is a sucrose fermenter, meaning it grows yellow on TCBS agar and can be ID’d in the stool.
Vibrio cholerae
The natural habitat of Vibrio cholerae is where? How is it transmitted?
salt water; fecally contaminated water
Serotypes 01 and 0139 of Vibrio cholerae are associated with disease. Which one doesn’t need toxin to cause disease?
01
Vibrio cholerae causes cholera. Describe the incubation period, onset, and symptoms
incubation: 1-3 days
onset: sudden
symptoms: NO FEVER, vomiting, severe but painless diarrhea, muscle cramps, hypovolemic shock, metabolic acidosis, hypokalemia
What type of stools does one produce when they have cholera?
rice water stools (mucus flecks)
Pathogenic strains of Vibrio cholerae are not capsulated. What is the significance of this?
infection confined to GI tract
This virulence factor of Vibrio cholerae is a bacteriophage encoded toxin with a co-regulated pilus - allows adherence and phage binding
cholera toxin
These two bacteria are curved Gram (-) rods that are oxidase positive, have darting motility. They are non-sucrose fermenters, meaning they grows green on TCBS agar and can be ID’d in the stool.
Vibrio parahaemolyticus and Vibrio vulnificus
Vibrio parahaemolyticus and Vibrio vulnificus require what? How do they infect?
salt; seafood/water
What diseases do Vibrio parahaemolyticus and Vibrio vulnificus cause?
Vibrio parahaemolyticus: gastroenteritis (diarrhea w/ no blood); wound infections from water
Vibrio vulnificus: Septicemia (after eating raw oysters); wound infections from water - erythema, pail bullae, necrosis
Vibrio vulnificus has enhanced virulence with high ___
iron
Vibrio parahaemolyticus has virulence factor that leads to increased Ca, and thus Cl loss. What is the name of this?
thermostable direct hemolysin (TDH)
This is a Gram (-) curved rod. It is oxidase positive and grows on TCBS agar, not halophile.
Aeromonas hydrophila
Aeromonas hydrophila is free living in fresh and salt water. What is the source of infection?
undercooked seafood; water
What diseased does Aeromonas hydrophila cause?
gastroenteritis, wound infections, and system diseases in IC patients
This bacteria is a Gram (-) curved or S-shaped rod. It can’t ferment/oxidize carbohydrates. It has darting motility. It grows on Campy-BAP media and MCCD agar
Campylobacter sp.
Campylobacter sp. (C. jejuni) is the #1 cause of bacterial _____ in the US.
gastroenteritis
note: can come from poultry, milk, meat, or H20
Infection by Campylobacter sp. is more common in what season? Transmission from person to person is ____
summer; low (high dose necessary)
Describe the progression of the gastroenteritis caused by C. jejuni - incubation, onset, and symptoms
incubation: 2-4 days
onset: HA, myalgia, malaise 12-48 h
symptoms: onset followed by diarrhea, fever, fecal leukocytosis, abdominal pain; no blood to bloody loos stools are possible
Gastroenteritis from C. jejuni causes 20-40% of ____-____ syndrome
Guillain-Barre
In regards to disease caused by types of Campylobacter sp., this type causes septicemia
C. fetus
Describe the virulence of C. jejuni
endocytosed by MC, epithelial cells and M cells -> host cell death, bowel ulceration, inflammation, EOSINOPHILS infiltrate the lamina propria
Describe the virulence of C. fetus
has capsule that allows it to infect systemically
This is a Gram (-) spiral rod with 4-6 polar flagella. It’s ID’d by Urea breath test and serological tests for IgG. It’s oxidase positive
H. pylori
How is H. pylori spread?
fecal-oral or oral-oral
What two diseases does H. pylori cause?
Chronic Gastritis; Gastric and Duodenal ulcers - increased risk of stomach cancer and gastric MALT lymphoma
H. pylori makes a ton of virulence factors. Urease is an important one. What does it do?
produces ammonia to raise pH, allows survival in stomach
