Simple pulmonary eosinophilia is characterized by abnormal chest X-ray findings. These vary -- the abnormality may appear in one part of the lung at one time, but the next X-ray may show no pathology or a problem in a different part of the lung. The abnormal X-rays are accompanied by a rise in the number of eosinophils (a type of white blood cell which is probably involved in allergies) in the blood. The disease is usually self-limited so it often resolves itself without treatment.
Alternative Names
Pulmonary infiltrates with eosinophilia; Eosinophilic pneumonia; Loeffler's syndrome
Causes, incidence, and risk factors
Loeffler's syndrome appears to be caused by an allergic reaction. A common cause is the migration of the parasitic worm Ascaris lumbricoides through the respiratory tract. Proteins on the surface of the worm probably incite this allergic reaction. Other parasites of the Ascaris family may also cause the syndrome. Additional possible causes include allergies to medications, for example, sulfonamide antibiotics.
Signs and tests
Listening to the chest with a stethoscope ( auscultation ) may reveal rales, which are crackle-like sounds that suggest inflammation of the lung tissue.
A bronchoscopy with washing may show a large number of eosinophils.
Sputum, bronchoscopically-obtained washing and gastric lavage may reveal larvae of the Ascaris worm. A CBC or WBC count shows increased white blood cells, particularly eosinophils .
chest X-ray usually reveals abnormal shadows (infiltrates) that disappear with time, or may reappear in different areas of the lung.
Treatment
If a cause is found, therapy consists of removing the offending drug or treating the infection with antibiotic (anti-parasitic) therapy.
Expectations (prognosis)
The disease often resolves without treatment. If treatment is needed, the response is usually good. However, relapses can occur.
Calling your health care provider
See your health care provider if you have symptoms that may be linked with this disorder.
Prevention
This is a rare disorder. Many times, the cause cannot be found. Minimizing exposure to possible risk factors (certain medicines, some metals) may reduce risk.