Acute pulmonary eosinophilia (Loeffler's syndrome)

Alternative names:

eosinophilic pneumonia; Loeffler's syndrome; pulmonary infiltrates with eosinophilia

Definition:

Acute pulmonary eosinophilia is a self-limiting inflammation of the lungs associated with infiltration of eosinophils (a type of white blood cell that increases in number in response to allergies or inflammation) in the lungs and blood.

Causes, incidence, and risk factors:

Causes may include exposure to various drugs, parasitic infestation (especially ascariasis in children), nickel exposure, recent blood transfusion, or lymphangiogram. Often, the cause remains undetermined, although a response by the immune system to a sensitizing antigen is suspected. Lung infiltrates show a large amount of eosinophils, a type of white blood cell. The incidence is 6 out of 100,000 people.