[A case of Nocardia farcinica pneumonia treated with sulfamethoxazole-trimethoprim monitoring its serum concentration].

A 75-year-old male suffered from interstitial pneumonia in December 2000 and treated with predonisolone. The treatment was effective, and the dosage of predonisolone had been gradually tapered. In January 2001, when the dosage was 30 mg/day, he complained of cough and yellowish sputum.