A Case of Propylthiouracil-induced Lung Injury Presenting Infiltrative Opacities in the Right Lower Lobe with a Persistantly High Titer of Serum ANCA

Abstract

Case. A 66-year-old woman had been treated with propylthiouracil (PTU) for hyperthyroidism since the age of 52. She was admitted because of a productive-cough and infiltrative shadows in the right lower lobe on chest X-ray and CT images. The serum level of myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) was very high (9400 EU). PTU was discontinued, and fiberoptic bronchoscopy was performed. The bronchoalveolar lavage fluid was not bloody, but contained Pasteurella multocida. The histopathological examination of the biopsy specimen obtained by a transbronchial lung biopsy revealed non-necrotizing vasculitis and an organizing pneumonia pattern. PTU induced pneumonia with vasculitis was diagnosed and she was treated with antibiotics with no administration of PTU. Although the high titer of serum MPO-ANCA persisted, her symptoms and chest radiograph findings gradually improved. Conclusion. While pulmonary alveolar hemorrhage with ANCA associated vasculitis caused by PTU have been reported, there have been few reports of lung injury induced by PTU. This report presented a case of PTU-associated lung injury. We discussed the pathological findings and the involvement of an infection.