16. c. Legionella Pneumophilia Flashcards
How does legionella pneumophilia get into the body?
Inhalation of aerosols from contaminated water
What helps LP adhere to cells?
Pili
outermembrane proteins
What enzymes are produced by LP?
Protease Phosphatase Lipase DNAse RNAse
What toxin is produced by LP?
LPS
Where does LP replicate?
Within alveolar macrophages
What group of people are more likely to get Legionnaires’ disease?
Males aged 50-60
Smokers
Immunosuppressed
What is the incubation period for Legionnaires’ disease?
2-10 days
What are the symptoms of Legionnaires’ disease?
Fever
Chills
Dry cough
Headache
What other organs may become involved in Legionnaires’ disease?
GIT
CNS
Liver
Kidneys
What can kidney involvement result in?
Proteinuria
Haematuria
Hyponatraemia
What does LP look like under the microscope?
Non-capsulated gram - bacillus
Is LP aerobic or anaerobic?
Strict aerobe
What agar can LP grow in?
BCYE agar
What samples can be sent to the lab?
Sputum
Tracheal aspirate
BAL
What test is used to confirm Legionnaires’ disease?
Urinary antigen detection
How is Legionnaire’s disease diagnosed using serology?
4 times increase between onset and 2 weeks later
What is used to see LP instead of a gram stain?
Immunofluorescent microscopy
Why are B-lactams not effective in treating Legionnaire’s disease?
Drugs need to penetrate the cell to be effective as legionella is intracellular
What antibiotics can be used to treat Legionnaire’s disease?
Levofloxacin
Azithromycin
Clarithromycin
What antibiotic can be used for the seriously ill?
Rifampicin
How can Legionnaire’s disease be prevented?
Pay attention to plumbing
