LearningRadiology - Aspiration pneumonia

Aspiration Pneumonia

• Occurs in gravity dependent portions of the lung

• Posterior segments of the upper lobes

• Lower lobes, especially right-sided

• Predisposing conditions include:

• CNS disorders, intoxication, mental retardation, seizure disorders, recent anesthesia, swallowing disorders

• Acute aspiration may lead to a fleeting infiltrate when it is non-infected

• Anaerobic organisms from GI tract can produce longer lasting pneumonia

• Chronic aspiration pneumonia results from repeated aspiration of foreign material over a prolonged time

• Zenker’s diverticulum

• Achalasia

• TE fistula

• Neuromuscular diseases

• Chronic reflux

• Lipoid pneumonia

• Mineral oil (used as a laxative)

• Oily nose drops (not used anymore)

Clinically

• Symptoms include low grade fever, productive cough and choking on swallowing

X-Ray

• Fleeting infiltrate (lasts one or two days) if bland and non-infected

• Consolidation of lobe if infected with anaerobic organisms or if aspiration of un-neutralized HCl

• When chronic, the disease usually starts alveolar and becomes interstitial as the macrophages incorporate the aspirated material

• May present as a mass when chronic

WH/’91,’93