[Localised aspergillosis of the lung caused by Aspergillus niger].

A 51-year old man with a history of pulmonary tuberculosis suffered an exacerbation without demonstration of tubercle bacilli. The mycological examination of sputum specimens discovered an infection with Aspergillus niger. Diagnosis was confirmed by the pure culture of this fungus in bronchial mucus and the cultural and histological identification in surgical material. As a histological feature strong double-refractile crystalline material was found in fungi and surrounding lung tissue (wall of cavern), probably oxalate crystals, developed from oxalic acid, produced by Aspergillus niger.