A case of eosinophilic pneumonia induced by lettuce.

A 56-year-old female lettuce farmer was admitted to the hospital with a low-grade fever, worsening cough, and dyspnoea. A blood test revealed eosinophilia and a high serum IgE concentration. The 3-year follow-up showed that her total IgE level increased in December, peaked in May, and suddenly decreased in August. This result was consistent with the lettuce harvest season. A chest x-ray taken on admission showed an infiltrative shadow in the upper lung field. Chest CT revealed patchy ground glass opacity on the upper lung field and thickening of the bronchial wall. The bronchoalveolar lavage fluid contained 8% eosinophils. She was treated with prednisolone, and her symptoms and radiological findings improved. The 37 kDa protein that reacted with the patient's sera was identified by immunoblot analysis.