Pulmonary Infections w/ Gram (-) Bacteria

Question 1

Klebsiella & Enterobacter

Answer 1

Encapsulated bacilli
Inhaled & multiply in alveolar spaces
Pulmonary parenchyma becomes consolidate, caviation, *thick mucoid sputum
* can be complicated by fulminating septicemia

Question 2

Legionella pneumophila

Answer 2

*reacts poorly w/ gram stains
Inhalation of aerosols from contaminated sources (bodies of water), Not contagious
(legionnaires disease) Pneumonia-terminal bronchioles of alveoli, phagocytosed by alveolar macrophages where they replicate, block fusion w/ lysosome
Pontiac Fever- self limited, flu like illness w/ fever. No evidence of pulmonary consolidation

Question 3

Pseudomonas aeruginosa

Answer 3

*highly antibiotic resistant opportunistic pathogen
Produces proteoglycans that surrounds & protects from mucocilliary action, complement, phagocytes
Has elastase, alkaline protease, cytotoxin aid in forming necrotizing lesions.
Invades small BV producing vascular thrombosis & hemorrhagic necrosis (lungs, skin)
Ecthyma gangrenosum

Question 4

Burkholderia pseudomallei

Answer 4

Melioidosis (Rangoon Beggars Disease)
Can enter open wound or through inhalation
Acute- pulmonary infection ranging from mild tracheobronchitis to an overwhelming cavitary pneumonia.
Chronic- persistent localized infection of the lungs, skin, bones. Lesions are suppurative or granulomatous abcesses/