[Levofloxacin-induced eosinophilic pneumonia complicated by bronchial asthma]

A 76-year-old woman who had complained of cough and productive sputum since mid-January, 1999, was admitted to our hospital with fever and dyspnea on February 4, 1999. She had been treated with levofloxacin at an outpatient clinic. On admission, she had orthopnea, and auscultation revealed coarse crackles and wheeze in the bilateral lung fields. Chest x-ray and CT films showed non-segmental infiltration in bilateral lung fields. Laboratory data revealed eosinophilia in peripheral blood (= 24%) and sputum (= 10%), airflow limitation, hypoxemia (PaO2: 46 Torr), and increased airway responsiveness to methacholine (Dmin: 0.127 units). A bronchoalveolar lavage (BAL) fluid showed increased total cells and a 55% increase in eosinophils, and CD4/CD8 ratio was decreased to 0.8. In addition, IL-5 was increased in BAL fluid. Transbronchial lung biopsy specimens revealed infiltrations of eosinophils in the alveolar and interstitial compartments. Histological features of the bronchial biopsy specimens included increased eosinophils in the submucosa and goblet cell metaplasia. The woman was diagnosed with eosinophilic pneumonia complicated by bronchial asthma. She was given theophylline, pranlukast hydrate, and an inhaled beta 2 receptor agonist (procaterol hydrochloride), and pre-admission drugs including Levofloxacin were discontinued. Her symptoms were improved, peak expiratory flow rate and PaO2 increased, airway responsiveness to methacholine decreased (Dmin: 0.615 units), and radiographic abnormalities disappeared without steroid therapy. A leukocyte migration test for levofloxacin was weakly positive. An environmental provocation test in the patient's home gave negative results. A challenge test for levofloxacin was not performed due to a lack of informed consent. Based on these findings, we diagnosed this case as levofloxacin-induced lung injury manifesting as eosinophilic pneumonia complicated by bronchial asthma. Levofloxacin should be added to the list of agents that can produce eosinophilic pneumonia.