Chapter 10: Hospital-Acquired Gram-Negatives Flashcards
What are the Hospital-acquired infections?
4 W’s
Wind: Penumonia - ventilation, intubation
Water: UTI - Foley
Wound: Surgery
Wires: bloodstream infection - intravenous
What are the 4 often highly resistant gram-negative bacteria?
Pseudomonas, Acinetobacter, Stenotrophomonas and Burkholderia
Pseudomonas aeruginosa
obligate aerobic (non-lactose fermenter) Gram-negative rod Motile: virulence Produces pyoverdin (green pigment) and pyocyanin (blue pigment) Grape-like scent Weak invasive Exotoxin A: like diphtheria toxin
What are the Pseudomonas aeruginosa infections?
BE PSEUDO Burns Endocarditis Pneumonia Sepsis External Malignant otitis media UTI Diabetic osteomyelitis
Most ______ pts have their lungs colonized with Pseduomonas aeruginosa. What do these pts develop?
Who is highly susceptible to peumonia caused by Pseduo aeruginosa?
Cystic fibrosis
Chronic pneumonia which progressively destroys their lungs
Immunocompromised pts
Who have an increased risk of osteomyelitis (related to wounds) due to Pseudomonas aeruginosa?
Diabetic pts: Foot ulcers infected, infection penetrates into bone
IV drug abusers: vertebrae or clavicle
Children: puncture wounds to foot wearing tennis shoe
How does Pseudomonas aeruginosa lead to sepsis?
Infected “wires” or catheters, or from burn-wounds, water, wind etc
What are frequent causes of right heart valve endocarditis in IV drug abusers?
Staphylococcus aureus
Pseudomonas aeruginosa
Malignant external otitis
Pseudomonas external ear canal infection burrows into the mastoid bone
Primarily in elderly diabetic pts
Burkholderia cepacia
Oxidase-positive aerobic gram-negative bacillus
Virulence: Extremely antibiotic resistant
Grow in water, soil, plants, animals
Infection in burn and ventilated pts
Who has the greatest risk for Burkholderia cepacia?
Cystic fibrosis
Asymptomatic carriage, bronchiectasis (dilated infected airways) or rapidly progressive pneumonia with bacteremia
Stentotrophomonas maltophilia
Colonizer
Part of normal respiratory flora
Can cause pneumonia, line-related bacteremia
Virulence: extremely antibiotic resistant
Acinetobacter
Virulence: multiple acquired mechanisms of antibiotic resistance
Aerobic gram-negative bacteria
Soil and water
Acinetobacter baumanni
Survive on environmental surfaces: increase transmission in healthcare settings
Cause: HAP, line-related bactermias, burn infections, foley UTI,
May appear gram-positive or look like Neisseria : can be coccobacillary (short rods) or coccal in appearance, or diplococci on solid media
