E1- Bacterial Pneumonia II Flashcards by Catherine sendek

What are the most common pathogens of HAP?

Pseudomonas aeruginosa*
Stapholococcus aureus
Klebsiella pneumoniae

How well did you know this?

Not at all

Perfectly

Is Pseudomonas aeruginosa gram positive or gram negative? What shape?

Gram negative bacillus

How well did you know this?

Not at all

Perfectly

What type of environments does Pseudomonas aeruginosa like?

Wet envrionements (cut flowers, food, sinks, toilets, dialysis equipment, disinfectants)

How well did you know this?

Not at all

Perfectly

What color is Pseudomonas aeruginosa?

Blue-green

Pyoverdin, pyocyanin

How well did you know this?

Not at all

Perfectly

What is unique about Pseudomonas aeruginosa?

Non-fermenting

How well did you know this?

Not at all

Perfectly

What can Pseudomonas aeruginosa use as a terminal electron acceptor?

Nitrate

How well did you know this?

Not at all

Perfectly

What kind of pathogen is Pseudomonas aeruginosa?

Opportunistic, rarely infects healthy individuals

How well did you know this?

Not at all

Perfectly

What are the five virulence factors of Pseudomonas aeruginosa?

Adhesins
Alginate capsule
Pyocyanin
Exotoxin A
Elastases

How well did you know this?

Not at all

Perfectly

What virulence factors of Pseudomonas aeruginosa is important for cyclic fibrosis patients?

Alginate capsule

Inhibits mucocilary escalator

How well did you know this?

Not at all

Perfectly

How does pyocyanin act as a virulence factor in Pseudomonas aeruginosa?

Catalyze ROS and causes tissue damage

How well did you know this?

Not at all

Perfectly

What elastases does Pseudomonas aeruginosa have? How do they work?

LasA and LasB

Work synergistically to degrade elastin (30% of the lung tissue is elastin)

How well did you know this?

Not at all

Perfectly

What diseases can Pseudomonas aeruginosa cause?

Pneumonia (HAP)*
Urinary tract
Eye, ear, skin
Second leading cause of infection in burn pts
Common cause of death in cystic fibrosis pts
Sepsis

How well did you know this?

Not at all

Perfectly

What population commonly gets chronic and recurrent Pseudomonas aeruginosa infections in the respiratory tract?

Cystic fibrosis pts

How well did you know this?

Not at all

Perfectly

How is Pseudomonas aeruginosa pneumonia (HAP) dx?

Gram stain

Culture

How well did you know this?

Not at all

Perfectly

Why is treatment of Pseudomonas aeruginosa pneumoniae (HAP) difficult?

Notoriously resistant to abx (capsule)
Pts are typically immunocompromised
Acquisition of resistance mediators

How well did you know this?

Not at all

Perfectly

Can you prevent a Pseudomonas aeruginosa infection?

No, you can only hope to contain it
Prevent contamination of sterile equipment
Prevent pt to pt spread

How well did you know this?

Not at all

Perfectly

What are the common pathogens that cause atypical pneumoniae?

Legionella pneumoniae
Mycoplasma pneumoniae
Chlamydophila pneumoniae

How well did you know this?

Not at all

Perfectly

What disease can mycoplasma pneumoniae cause?

Atypical CAP

How well did you know this?

Not at all

Perfectly

What is unique about mycoplasma pneumoniae?

No cell wall/peptidoglycan

What abx can you not use to tx mycoplasma pneumoniae? Why?

Beta lactams

They do not have a cell wall

How does atypical CAP caused by mycoplasma pneumoniae present?

Non productive cough that lasts 1-2 months
Fever (not usually in children <5)
Crackles
Headache
Chest pain
Non specific rash

Does mycoplasma pneumoniae infection lead to long lasting immunity?

No, relapses are common

How is mycoplasma pneumoniae transmitted?

Person to person via respiratory droplets

How does mycoplasma pneumoniae attach to the respiratory epithelium?

Via attachment organelle leading to the development of ciliostasis, allowing the bacteria to colonize

What does Mycoplasma pneumoniae release that damages the epithelial layer?

H2O2

What is ciliostasis and how does it work?

Damage to the ciliated epithelium (paralysis) Halts the mucociliary escalator, preventing the host from clearing the bacterium from the airway Bacterium colonized

How is mycoplasma pneumoniae atypical pneumoniae dx?

CXR, culture, serological testing

Is Chlamydia pneumoniae gram positive or negative? What shape?

Gram negative | Coccus

What type of pathogen is Chlamydia pneumoniae?

Obligate intracellular parasite

What is the infectious stage of Chlamydia pneumoniae called?

Elementary bodies

What is the intracellular stage of Chlamydia pneumoniae called?

Reticulate bodies

How does atypical pneumoniae caused by Chlamydia pneumoniae present?

Generally asymptomatic or mild illness in adults | Persistent non productive cough and malaise for weeks to months

How is Chlamydia pneumoniae transmitted?

Person to person via respiratory droplets

What causes illness from a Chlamydia pneumoniae infection?

Tissue destruction during bacterial replication and the associated inflammatory response

Does infection with Chlamydia pneumoniae provide long lasting immunity?

What is the most effective tool for dx Chlamydia pneumoniae?

Serology | MIF test looks for IgM and IgG

Is Legionella pneumoniae gram positive or negative? What shape?

Gram negative bacillus

What species of Legionella pneumoniae causes majority of human infections?

L. Pneumohila serotype 1

What diseases can Legionella pneumoniae cause?

Pontiac fever | Legionnaires disease

How does Pontiac fever present?

Fever, chills, malaise, myalgia, headache, NO sign of pneumonia Self limited illness Sxs last for 2-5 days Resolved without tx

How does legionnaires disease present?

Fever, chills, non productive cough, headache, GI/neuro sxs Severe, acute atypical pneumonia with a high mortality rate

What causes death in legionnaires disease?

Shock or respiratory failure

Where does Legionella pneumoniae grow?

Aquatic environments

What does Legionella pneumoniae use as hosts?

Amoeba

How is Legionella pneumoniae transmitted?

Aerosolized biofilms (no person to person transmission)

Where does growth of Legionella pneumoniae occur in humans?

Alveolar macrophages

How is Legionella pneumoniae dx?

Culture is gold standard (buffered charcoal yeast extract) | Rapid test for antigen in the urine (only detects serotype 1)