<B>Bronchopneumonia </B>

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Bronchopneumonia

Etiology:

• Variety of aspirated organisms.
• Organism dependent on whether community acquired in previously healthy patient (more likely Streptococcus) or
• Community acquired in patient with depressed pulmonary defenses such as a patient with chronic bronchitis (more likely Klebsiella or Pseudomonas spps) or
• Hospital acquired

Pathogenesis:

• Aspiration of organisms results in inflammation and necrosis of underlying parenchyma
• Tends to scar if pulmonary septae are destroyed

Epidemiology:

• Common in hospitalized patients and contributes to the cause of death in moribund patients
• Most common community acquired pneumonia as well

General Gross Description:

• Patchy distribution particularly around small airways
• Nodular, elevated, firm, airless regions
• Range from red to gray depending on age of the lesion
• Can become confluent to mimic lobar pneumonia

General Microscopic Description:

• Bronchocentric lesions
• Neutrophils fill airway and surrounding alveoli
• Parenchymal destruction depends on organism
• Uninvolved parenchyma may contain acellular pink edema

Clinical Correlations:

• Clinical course dependent on underlying disease processes
• Patients present with fever, cough and purulent sputum

References:
• Cotran RS, Kumar V, Robbins SL. Robbins Pathologic Basis of Disease. 5th edition. W.B. Saunders Philadelphia 1994. pp.694-698.