Lipid Pneumonia

Lipoid pneumonia is a specific form of lung inflammation (pneumonia) that develops when lipids enter the bronchial tree. The disorder is sometimes called cholesterol pneumonia in cases where that lipid is a factor.

Signs and symptoms

The pneumonia presents as a foreign body reaction causing cough, dyspnea, and often fever. Hemoptysis has also been reported.

Causes

Sources of such lipids could be either exogenous or endogenous.

Exogenous: from outside the body. For example, inhaled nose drops with an oil base, or accidental inhalation of cosmetic oil. Amiodarone is an anti-arrythmic known to cause this condition. Oil pulling has also been shown to be a cause. Fire breather's pneumonia from the inhalation of hydrocarbon fuel is a specific variant. At risk populations include the elderly, developmentally delayed or persons with gastroesophageal reflux. Switching to water-soluble alternatives may be helpful in some situations.

Endogenous: from the body itself, for example, when an airway is obstructed, it is often the case that distal to the obstruction, lipid-laden macrophages and giant cells fill the lumen of the disconnected airspace.

Appearance

The gross appearance of a lipid pneumonia is that in which there is an ill-defined, pale yellow area on the lung. This yellow appearance explains the colloquial term "golden" pneumonia.

At the microscopic scale foamy macrophages and giant cells are seen in the airways, and the inflammatory response is visible in the parenchyma.

Treatment

Treatment is with corticosteroids and possibly intravenous immunoglobulins.

Prognosis

Endogenous lipoid pneumonia and non-specific interstitial pneumonitis has been seen prior to the development of pulmonary alveolar proteinosis in a child.

History

Laughlen first described lipid pneumonia in 1925 with infants that inhaled oil droplets. It is a condition that has been seen as an occupational risk for commercial diving operations but documented cases are rare.