Ch. 37 - Legionella

Question 0

Legionella pneumophila pathogenesis

Answer 0

Inhalation (resp disease)

Intracellular
Inhibit phagolysosome fusion

Macs secrete cytokines (inflammation)

Enzyme production (kill host cell upon lysis of intracellular vacuole)

Cell-mediated immunity (humoral minor)

Found in water
Survived chorine and high temps

Question 1

Legionella pneumophila

Answer 1

Thin pleomorphic G-b

Obligate aerobes

NFB
Amino acid metabolism

90% disease

Serotypes 1-6

Fastidious - cysteine & iron (sucks iron out of cells –> virulence)

GS poor, use tissue silver stain

Question 2

Legionella pneumophila disease

Answer 2

Mostly asymptomatic lung infection

Pontiac fever - self-limiting fever antib treatment

Legionnaires disease - legionellosis; systemic, multi organ disease, pneumonia, 15% healthy and 75% not will die

Question 3

Legionella pneumophila diagnosis

Answer 3

Tissue silver stain

Antibody fluorescence

Urine Ag test

ELISA
4X or more Ab titer