Lipoid pneumonia (LP) is a rare, non-infectious condition characterized by the presence of fat (lipids) in the alveoli of the lungs. Fat molecules in the lungs cause inflammation, filling the alveoli sacs with fluid and pus. 

This article discusses the types, symptoms, causes, diagnosis, and treatment of LP.

Types of Lipid Pneumonia

There are two types of lipoid pneumonia:

  • Endogenous form: This results from systemic conditions, such as Krabbe and Niemann-Pick disease, in which lipids from within the lung itself accumulate. This may be the case during injury to the lungs, when alveolar cell walls are damaged and release lipids into the alveolar sacs or when lipids build up in lipid storage diseases. Exogenous form: This results from inhaled or aspirated oils or fats. This may occur after aspiration, such as aspiration of mineral oil as a treatment for constipation, or ingestion of excessive use of lip balm or petroleum jelly when applied around the mouth and nose areas.

Symptoms

Symptoms can vary significantly among individuals, ranging from asymptomatic to severe, life-threatening disease.

The symptoms that are most commonly observed in cases of lipoid pneumonia include:

  • Fever (usually high intermittent fevers)Weight loss CoughShortness of breath (dyspnea)Chest painCoughing up blood (hemoptysis)

Common Causes

The causes of lipoid pneumonia depend on the type of lipoid pneumonia.

Endogenous Lipoid Pneumonia

Endogenous lipoid pneumonia is usually related to fat storage and fat metabolism diseases, such as:

  • Gaucher disease
  • Niemann-Pick disease
  • Fabry disease
  • Farber’s disease
  • Gangliosidosis
  • Krabbe disease
  • Metachromatic leukodystrophy
  • Wolman’s disorder

Excessive fat storage that enters lung cells can cause inflammation and cell death, damaging lung tissue, sometimes irreparably. 

Exogenous Lipoid Pneumonia

Exogenous lipoid pneumonia is related to inhaling or ingesting substances that are oily or fatty in nature. Many people do not know the dangers of doing this until it is too late. The most common causes are:

  • Vaping: The cartridges in vape pens contain oil compounds that can get into your lungs and cause damage.Laxatives: Taking mineral oil laxatives, or other oil-based laxatives—like cod liver oil, paraffin oil, or glycerine—is the most common cause of lipoid pneumonia. Paints and lubricants: Anyone who works with products that contain crude minerals such as lubricants, machine oil, paints, or pesticides at work or at home is at risk of developing lipoid pneumonia.Fire eaters: These performers sometimes breathe in petroleum products, which can cause lung problems.‌Personal care products: Regularly using some personal care products can lead to lipoid pneumonia.

Diagnosis

High-resolution computed tomography (HRCT) is the best imaging modality for the diagnosis of lipoid pneumonia.

Substances That Can Cause Exogenous Lipoid Pneumonia

Exogenous lipoid pneumonia has been caused after inhaling one of the following substances: 

Although the radiologic findings of exogenous lipoid pneumonia on HRCT can be nonspecific, lipid-containing opacities on HRCT are diagnostic if there is a history of use or occupational exposure to lipid-containing materials.

If the cause of your lipoid pneumonia is endogenous, such as the result of lipid storage disease or pulmonary alveolar proteinosis, lung biopsy is needed to confirm the diagnosis because imaging is often non-specific and inconclusive.

Treatment

There is currently no consensus on the best therapeutic option for the treatment of lipoid pneumonia, and treatment regimens—especially in those without symptoms—remain controversial. Treatment is primarily conservative and supportive.

In cases of exogenous lipoid pneumonia, it is imperative that you stop using the substance in question immediately. If you are experiencing symptoms, your healthcare provider may use lung lavage — lung washing to flush the fat build-up from the lungs — and prescribe immunoglobulins and systemic corticosteroids.

Other treatments might include:

  • Enzyme replacement therapy (ERT): Injecting alpha-glucosidase directly into the bloodstream. ERT helps the body to break down glycogen and prevents its toxic buildup.
  • Oxygen support: Increases the amount of oxygen your lungs receive and deliver to your blood.
  • Respiratory therapy‌: Exercises and treatments that help patients recover lung function,

Summary

Lipoid pneumonia (LP) is an inflammatory condition that results from accumulation of lipids in the alveoli. The cause of LP can be either exogenous or endogenous based on the source of the fat in the lungs.

A Word From Verywell

Although there is no standard of care for the treatment of lipoid pneumonia, the outlook for lipoid pneumonia is usually positive if treatment is initiated immediately and you have good lung health.

Still, if you are experiencing high fever, shortness of breath, chronic cough, or coughing up blood,—especially after inhaling or ingesting household products that contain oils or fat—you should seek immediate medical attention.