ABSTRACT
To report a case of Churg-Strauss syndrome who had asthma and allergic rhinitis treated with montelukast. A nonsmoking 59-year-old woman presented with fever, hemoptysis and dyspnea. Past medical history included allergic rhinitis and asthma which were diagnosed 18 years ago. The asthma was treated successfully with inhaled salmeterol and beclamethasone. She also received montelukast [10 mg/day] for 3 years. Although her chest X-ray was normal a week earlier, she had widespread bilateral pulmonary infiltrates on admission. She had leukocytosis [12.5 x 109/l] with eosinophilia [15.6%]. Her total IgE count was 550 U/ml. Testing for protoplasmic-staining antineutrophil cytoplasmic antibodies was positive. Bronchoalveolar lavage could not be performed due to bronchospasm and severe hypoxemia; however, mucosal biopsies were obtained, which revealed eosinophil leukocytes in the lumen and walls of small vessels. She was diagnosed to have Churg-Strauss syndrome and had remarkable clinical improvement on day 5 with high-dose of oral prednisolone [50 mg/day]. Radiological improvement was detected at the end of the second week. This case shows the importance of being aware that leukotriene receptor antagonists could cause Churg-Strauss syndrome, in spite of the uncertainty about its mechanism