What is lipoid pneumonia?

Lipoid pneumonia is a rare condition that occurs when fat particles enter the lungs. Lipoids, also known as lipids, are fat molecules. Pneumonia refers to inflammation of the lungs. Lipoid pneumonia is also called lipid pneumonia.

There are two types of lipoid pneumonia:

  • Exogenous lipoid pneumonia. This occurs when the fat particles enter from outside the body and reach the lungs via the nose or mouth.
  • Endogenous lipoid pneumonia. In this type, fat particles accumulate in the lungs, causing inflammation. Endogenous lipoid pneumonia is also known as cholesterol pneumonia, golden pneumonia, or in some cases idiopathic lipoid pneumonia.

Symptoms of both types of lipoid pneumonia vary from person to person. Many people don’t experience any symptoms at all. Others experience mild symptoms.

Symptoms of lipoid pneumonia tend to worsen over time. In some cases, they can become severe or even life-threatening.

Some common symptoms of lipoid pneumonia can include:

  • chest pain
  • chronic cough
  • difficulty breathing

Less common symptoms can include:

The cause of lipoid pneumonia depends on the type.

Exogenous lipoid pneumonia

Exogenous lipoid pneumonia occurs when a fatty substance is inhaled or aspirated. Aspiration occurs when you swallow a solid or a liquid “down the wrong pipe.” When matter enters the windpipe instead of the esophagus, it can end up in the lungs.

Once in the lungs, the substance causes an inflammatory reaction. The severity of the reaction often depends on the type of oil and the length of exposure. Severe inflammation can permanently damage the lungs.

Mineral oil–based laxatives are among the most common inhaled or aspirated substances to cause exogenous lipoid pneumonia.

Other fatty substances that can cause exogenous lipoid pneumonia include:

  • oils present in foods, including olive oil, milk, poppyseed oil, and egg yolks
  • oil-based medication and nasal drops
  • oil-based laxatives, including cod liver oil and paraffin oil
  • petroleum jelly
  • kerdan, a type of petroleum used by performers who “eat” fire
  • oils used at home or in the workplace, including WD-40, paints, and lubricants
  • oil-based substances found in e-cigarettes

Endogenous lipoid pneumonia

The cause of endogenous lipoid pneumonia is less clear.

It often occurs when an airway is blocked, such as by a lung tumor. Blockages can cause cells to break down and become inflamed, which results in a buildup of debris. This debris might include cholesterol, a fat that’s difficult to break down. As cholesterol accumulates, it can trigger inflammation.

The condition can also be brought on by the long-term inhalation of dust and other irritating substances, certain infections, and genetic problems with breaking down fats.

Certain risk factors can increase your likelihood of developing lipoid pneumonia. These vary according to the type of lipoid pneumonia.

Exogenous lipoid pneumonia

Risk factors for exogenous lipoid pneumonia include:

  • neuromuscular disorders that affect the swallow reflex
  • forced oil intake
  • gastroesophageal reflux disease (GERD)
  • snorting oil-based drugs
  • loss of consciousness
  • oil pulling
  • psychiatric disorders
  • throat or esophagus abnormalities, including hernias and fistulas
  • age
  • oral ingestion and aspiration of mineral oil used as a laxative

Endogenous lipoid pneumonia

Risk factors for endogenous lipoid pneumonia include:

Your doctor will conduct a physical exam and ask you about your symptoms.

Symptoms of lipoid pneumonia are similar to those of other lung conditions, such as bacterial pneumonia, tuberculosis, and lung cancer. As a result, lipoid pneumonia can be difficult to diagnose.

Most types of pneumonia are visible on a chest X-ray. However, a chest X-ray isn’t enough to identify which type of pneumonia you have.

You should tell your doctor if you remember inhaling or aspirating an oily substance before your symptoms appeared. This can help them identify exogenous lipoid pneumonia.

It’s also important to share any routine habits you have that involve the regular use of common oils such as lip balm, baby oil, chest vapor rubs, or petroleum jelly.

Your doctor might order other tests to confirm the diagnosis. Possible tests include:

  • bronchoscopies with bronchoalveolar lavage
  • CT scans
  • needle aspiration biopsies
  • pulmonary function tests

Treatment depends on the type and cause of lipoid pneumonia, as well as the severity of symptoms.

With exogenous lipoid pneumonia, eliminating exposure to the fatty substance is often enough to improve symptoms.

Your doctor might suggest using prescription anti-inflammatory medications, such as corticosteroids, to reduce inflammation caused by lipoid pneumonia.

Other treatments, including oxygen therapy and respiratory therapy, can make breathing easier for people with lipoid pneumonia.

Whole lung lavage may be used to ease symptoms of lipoid pneumonia caused by PAP. In this procedure, one of your lungs is filled with a warm saline solution, and then drained while under anesthesia.

Once diagnosed, lipoid pneumonia is treatable. Though there are few long-term studies of lipoid pneumonia, case studies suggest that the outlook for lipoid pneumonia is good. The outlook is also affected by overall lung health and the presence of other chronic lung diseases.

With exogenous lipoid pneumonia, eliminating exposure to the inhaled or aspirated fat can help relieve symptoms. Exogenous lipoid pneumonia isn’t always preventable. However, it helps to understand the risks of ingesting mineral oil and inhaling other oily substances.

If you’re experiencing symptoms of lipoid pneumonia, make an appointment to see a doctor as soon as possible.