Histologic:
fibrinopurulent : acute bacterial pneumonias
mononuclear interstitial infiltrates in viral and other atypical pneumonias
granulomas and cavitation seen in chronic pneumonia like TB
Bronchopneumonia:
patchy distribution of inflammation that generally involves more than one lobe.
initial infection of the bronchi and bronchioles with extension into the adjacent alveoli
lobar pneumonia :
the contiguous airspaces of part or all of a lobe are homogeneously filled with an exudate
visualized on radiographs as a lobar or segmental consolidation
Community-Acquired Acute Pneumonia
Streptococcus pneumoniae
Haemophilus influenzae
Moraxella catarrhalis
Staphylococcus aureus
Legionella pneumophila
Enterobacteriaceae (Klebsiella pneumoniae) and Pseudomonas spp.
Community-Acquired Atypical Pneumonia
Mycoplasma pneumoniae
Chlamydia spp. (C. pneumoniae, C. psittaci, C. trachomatis)
Coxiella burnetti (Q fever)
Viruses: respiratory syncytial virus, parainfluenza virus (children); influenza A and B (adults); adenovirus (military recruits); SARS virus
Nosocomial Pneumonia
Gram-negative rods belonging to Enterobacteriaceae (Klebsiella spp., Serratia marcescens, Escherichia coli) and Pseudomonas spp.
Staphylococcus aureus (usually penicillin-resistant)
Aspiration Pneumonia
Anaerobic oral flora (Bacteroides, Prevotella, Fusobacterium, Peptostreptococcus), admixed with aerobic bacteria (Streptococcus pneumoniae, Staphylococcus aureus, Haemophilas influenzae, and Pseudomonas aeruginosa)
Fulminant course
Chronic Pneumonia
Nocardia
Actinomyces
Granulomatous: Mycobacterium tuberculosis and atypical mycobacteria, Histoplasma capsulatum, Coccidioides immitis, Blastomyces dermatitidis
Necrotizing Pneumonia and Lung Abscess
Anaerobic bacteria (extremely common), with or without mixed aerobic infection
Staphylococcus aureus, Klebsiella pneumoniae, Streptococcus pyogenes
Pneumonia in the Immunocompromised Host
Cytomegalovirus
Pneumocystis carinii
Mycobacterium avium-intracellulare
Invasive aspergillosis
Invasive candidiasis
"Usual" bacterial, viral, and fungal organisms.
0 comments:
Post a Comment