Gram Negative Pathogens Part 3 (HAI and Respiratory Infections) Flashcards
T/F. Pseudomonas are obligate anaerobe.
False. Obligate aerobe
T/F. Pseudomonas are lactose fermenter and oxidase positive.
False. Lactose non fermenter and oxidase positive
What pigment provides Pseudomonas a green color?
pyoverdin
What pigment provides Pseudomonas a blue color?
pyocyanin
What are the common presentation/disease caused by Pseudomonas?
- Burn-wound infections
- Corneal infections
- Malignant external otitis
- Pneumonia
- Endocarditis
- UTI
- Osteomyelitis
- Sepsis
T/F. Pseudomonas are motile.
True.
T/F. Pseudomonas are hemolytic.
True. They have hemolysin.
T/F. Pseudomonas are kinase positive.
True. They have fibrinolysin
T/F. Pseudomonas are collagenase positive but elastase negative.
False. callogenase and elastase positive
T/F. Pseudomonas are phospholipase positive.
True.
Pseudomonas toxin is in the form of?
Exotoxin A
This organism is ubiquitous and may be transmitted via hands of healthcare workers and medical devices
Pseudomonas
What are the diagnostic procedure used to detect Pseudomonas?
Gram stain and culture
T/F. Acinetobacter are microaerophile organisms.
False. aerobic organisms
This bacterium is generally coccobacillus or coccus in shape but appears diplococci in solid medium.
Acinetobacter
What is the shape of acinetobacter?
generally coccus or coccubacillus but turns diplococcus in solid medium
T/F. Acinetobacter is non lactose fermenter and oxidase negative.
True.
How is Acinetobacter biochemically differentiated from Pseudomonas?
Both are non lactose fermenter but Acinetobacter is oxidase negative while Pseudomonas is oxidase positive.
What are the diseases caused by Acinetobacter?
*Burn infections
* Pneumonia
* Catheter- associated UTI
* Bacteremia
This microorganism is characteristically associated with catheter-associated UTI.
Acinetobacteria
This bacterium is known for its ability to acquire mechanisms of antibiotic resistance.
Acinetobacter
T/F. Acinetobacter is encapsulated.
True.
What is the treatment for Pseudomonas?
Antibiotic
What is the treatment for Acinetobacter?
Antibiotics
What are the diagnostic procedure used to detect Acinetobacter?
Gram stain and culture
This bacterium is easily mistaken for Neisseria and may be transmitted via hands of the healthcare worker and medical devices.
Acinetobacter
T/F. Haemophilus influenzae is aerobic organism.
True.
What is the shape of Haemophilus influenzae?
Short coccoid bacilli
What are the disease caused by Haemophilus influenzae?
Influenza
Meningitis
Sepsis
T/F. Haemophilus influenzae is non encapsulated.
False. encapsulated
T/F. Haemophilus influenzae are protease positive.
True.
Among the virulence factors associated with Haemophilus influenzae which allows attachment to host tissues?
Pilus
Culture of Haemophilus influenzae is done on what kind of medium?
Chocolate agar
Diagnostic procedure for detection of H. influenzae
Gram stain
Culture on chocolate agar
What is the treatment for H. influenzae?
antibiotics
T/F. Bordetella pertussis are motile organisms.
False.
What is the usual shape of Bordetella pertussis?
Small rod-shaped cells
T/F. Bordetella pertussis are oxidase and catalase negative.
False. They are oxidase and catalase positive.
T/F. Bordetella pertussis are nitrate, citrate and urea negative.
True.
What is the disease characteristically caused by Bordetella pertussis?
Whooping cough
What are the three stages of whooping cough?
Catarrhal stage (1-2 weeks; mild cold-like symptoms) –> Paraxysmal stage (1 month; severe coughing fits with whooping) –> Convalescent stage
At stage is whooping cough most contangious?
Catarrhal stage
T/F. A person on the convalescent stage of pertussis is not contagious.
True.
T/F. Bordetella pertussis are capsulated organisms.
True.
Bordetella pertussis toxins are in the form of?
Pertussis and tracheal toxin
Bordetella pertussis pilus in the form of?
Filamentous hemagglutinin (FHA) pilus
What are the virulence factors of B. pertussis?
- Pertussis toxin
- Tracheal cytotoxin
- Capsule
- Beta-lactamase
- Filamentous hemagglutinin (FHA) pilus
In treating pertussis caused by Bordetella pertussis, erythromycin is best given during what stage of the disease?
Catarrhal
Vaccine against Pertussis is contained in what trivalent vaccine?
Diphtheria, Tetanus, and Pertussis
Culture of Bordetella pertussis is carried out on what medium?
Bordet-Gengou media
What are the diagnostic procedures for the detection of B. pertussis?
Gram stain
Culture on Bordet-Gengou media
ELISA
PCR
T/F. Although it may also affect adults, infant less than 1 year old are at high risk Bordetella pertussis infection.
True.
T/F. Legionella pneumophila is an aerobic organism.
True.
T/F. Legionella pneumophila is a facultative anaerobic organism.
False. Facultative intracellular bacteria
This organism characteristically produces Legionnaires’s disease and pontiac fever.
Legionella pneumophila
What are the disease caused by Legionella pneumophila?
Legionnaires’ disease
Pontiac fever
What is lethal presentation of Legionella pneumophila infection?
Legionnaires’ disease/pneumonia
What is non lethal presentation of Legionella pneumophila infection?
Pontiac disease
This virulence factor of Legionella pneumophila inihibits macrophage phagosome and lysosome fusion.
Type IV secretion system
Among the virulence factor of Legionella pneumophila, these provide the organism attachment and invasion abilities.
Pilus and flagella
T/F. Legionella pneumophila is RNAse and phospholipase positive.
True.
This organism has type IV secretion system that inhibits macrophage phagosome and lysosome fusion
Legionella pneumophila
What are the treatment for L. pneumophila infection?
- Azithromycin
- Levofloxacin
- Doxycycline
Culturing L. pneumophila is carried out using what medium?
Charcoal yeast extract agar
What are the diagnostic procedures used in detecting L. pneumophila
Culture on charcoal yeast extract
ELISA
T/F. L. pneumophila may survive on biofilm.
True.
This organism caused an outbreak of pneumonia at an American Legion convention in Philadelphia in 1976.
Legionella pnuemophila (Legionnaires’ pneumonia)
This organism is known to be an intracellular parasite in Naegleria and Acanthamoeba.
Legionella pneumophila
T/F. Mycobacterium are acid-fast coccus.
False. Acid-fast bacillus
T/F. Both M. tuberculosis and leprae are obligate aerobe.
False. MT - obligate aerobe while ML - facultative intracellular parasite.
This genus of bacterium is known for its very slow growth of around 6 weeks.
Mycobacterium
T/F. Mycobacterium are catalase positive.
True.
T/F. Mycobacterium are non-motile and non capsulated.
True.
This presentation of tuberculosis is characterized by weight loss and low-grade fever.
Primary tuberculosis
This presentation of tuberculosis is characterized by infection of multiple organs.
Secondary tuberculosis
What are the virulence factors associated with Mycobacterium tuberculosis?
Mycosides (glycolipids limited in distribution to a single mycobacterium species)
-Cord factor
-Sulfatides
Siderophores
T/F. Mycobacterium tuberculosis does not have attachment pilus but contains exotoxin and endotoxin.
False. No pilus, exotoxin, or endotoxin.
Bactec which is a rapid culture system is used in culturing what organism?
M. tuberculosis
This organism can be detected by acid-fast staining of sputum sample.
M. tuberculosis
This test is used to detect prior exposure to Mycobacterium tuberculosis?
PPD (Purified Protein Derivative) skin test
What are the diagnositic procedures used to detect Mycobacterium tuberculosis?
- Acid-fast staining of sputum sample
- Bactec (rapid culture system)
- PPD skin test
- Chest x-ray
- PCR
What are the treatments for Mycobacterium tuberculosis?
- Isoniazid
- Rifampin
- Pyrazinamide * Ethambutol
- Streptomycin
This presentation of leprosy characterized by widespread and symmetrical skin lesions due to high load of M. leprae bacteria in the body. Significant proliferation of the bacterium usually caused by an compromised immune system that responds weakly to the infection.
Lepromatous leprosy
This presentation of leprosy characterized by well-defined, single or very few skin lesions due to relatively smaller load of M. leprae bacteria in the body. Curtailed proliferation of the bacterium usually caused by a intact immune system that responds strongly to the infection.
Tuberculoid leprosy
T/F. Mycobacterium leprae is a facultative intracellular parasite.
True.
Culturing M. leprae is done on?
animal models (cannot be grown on culture media)
Diagnostic procedures used to detect M. leprae
Grown on animal models
Skin and nerve biopsy
What are the treatment for M. leprae?
- Rifampin
- Dapsone
- Clofazimine