[A case of primary pulmonary nocardiosis with multiple pulmonary nodules successfully treated with moxifloxacin].

A 18-year-old man was admitted with fever. His chest radiograph and CT scan showed consolidation shadow in the right middle lobe and multiple nodules in both lungs. He was treated with meropenem and minocycline. After this antibiotic therapy, the consolidation shadow disappeared and the multiple nodules were slightly reduced in their size. Since filamentous bacteria suspicious of Nocardia grew transiently in the initial sputum culture, we started to treat him with oral sulfametoxazole-trimethoprim. However, because agranulocytosis was caused by sulfametoxazole-trimethoprim therapy, we had to change the anti-bacterial therapy to minocycline. Minocycline was not effective, and the nodules enlarged. For accurate diagnosis, we employed video-assisted thoracic surgery (VATS) to investigate the histological and bacterial analyses of the pulmonary nodules. Histological findings of the pulmonary nodule obtained by VATS revealed granuloma with central necrosis associated with neutrophilic micro-abscess. Filamentous gram-positive bacteria in pulmonary nodule tissue was stained positively with both Grocott and Ziehl-Neelsen staining. Taking these findings together, we diagnosed primary pulmonary nocardiosis. Three months after initiating moxifloxacin, the size of the multiple pulmonary nodules was markedly reduced. Our experience with this case suggests that moxifloxacin can be recommended for the treatment of pulmonary nocardiosis.