Lipoid Pneumonia

Lipoid Pneumonia

• Exogenous accumulation of fat in the lung most often from mineral oil:
• Older people who are constipated, have a swallowing disorder 2° neurologic disease
• In infants with feeding difficulties
• In the past, could be from oily nose drops
• Accumulation of fat in the lung may also occur from endogenous sources such as fat embolism, alveolar proteinosis lipid storage diseases
• Animal fatty acids (like fat embolus) produces hemorrhagic bronchopneumonia
• Mineral oil produces a giant cell foreign body reaction
• Starts as an alveolar infiltrate
• Moves to thicken interstitial septa, then
• Into macrophages enlarging lymphatics
• Finally produces a fibrosing reaction

X-ray

• Usually lower lobes with predilection for the right
• Alveolar consolidation, may be well-circumscribed
• May present as a peripheral mass with fuzzy or distinct margins simulating BrCa

Clinical

• Usually asymptomatic

Diagnosis

• Best method of DX is direct Bx
• Fat-laden macrophages are non-specific since they can be found in sputum of normals as well