What Is Lipoid Pneumonia?

Pneumonia, a disease wherein the lungs become boggy and inflamed, can be caused by anything that should not be in the lungs, such as germs or lipids. The two basic types of pneumonia are infectious pneumonia and aspiration pneumonia. When germs such as bacteria, fungi and viruses are the causative agents, it is called infectious pneumonia; when a noninfectious foreign substance is inhaled into the lungs, it is called aspiration pneumonia. Lipoid pneumonia is a type of aspiration pneumonia that derives its name from the word “lipid,” which simply means fat. It is a slowly progressive disease that can be treated effectively if diagnosed in its early stages.

Based on the causes, the pneumonia can be categorized as exogenous or endogenous. Exogenous lipoid pneumonia is caused by aspiration of a fatty substance not produced by the body. Examples of exogenous substances are petroleum jelly, mineral oil, animal oil or vegetable oil. These might be present in nasal drops, mouth sprays, oral lubricants, laxatives or traditional home remedies. The exogenous type occurs more commonly among elderly people who have defective respiratory passages and among children who are given oil-based medications and foods.

The body produces endogenous fatty substances. For instance, the body has white blood cells called macrophages that eat up or “phagocytose” the body’s waste substances, such as lipids or cholesterol. They are then called foamy macrophages. Foamy macrophages can accumulate in the lungs, leading to endogenous lipoid pneumonia. Conditions that can result in the endogenous type include Hodgkin’s disease, Gaucher’s disease and lung cancer.

When a lung biopsy is done, the affected area would appear pale yellow. This is similar to the actual appearance of solidified oil or fats, earning it the name “golden pneumonia.” Inflammatory cells and foamy macrophages could be seen through a microscope.

A person who has lipoid pneumonia may not have any physical complaints, and the condition may only be incidentally discovered through a chest X-ray or a computed tomography (CT) scan. Like any other type of pneumonia, the symptoms include low-grade fever, lung sounds called crackles and gradual weight loss. Other symptoms include a long-standing cough, chest pain and difficulty breathing or shortness of breath. The progress of this disease is slow, and it rarely causes emergencies. If untreated, complications include cavitations, or holes in the lungs; pleural effusion, or accumulation of fluid in the covering of the lungs; and respiratory failure.

Treatment is done by completely avoiding the substance causing the condition. The doctor might prescribe antibiotics if there is a coexisting bacterial infection. Corticosteroids and immunoglobulins are also used in treating lipoid pneumonia, because they reduce inflammation.