Application of metagenomic next-generation sequencing in diagnose the pulmonary infections caused by Aureobasidium melanogenum: A case report and review of the literature.

Aureobasidium melanogenum (A. melanogenum) is a black-yeast-like fungus widely present in nature that rarely causes human infections. We report a case of pulmonary infection caused by A. melanogenum in a 60-year-old male farmer, who initially presented with severe paroxysmal coughing and right-sided chest pain and was initially misdiagnosed with tuberculosis or lung cancer. While sputum cultures were negative, metagenomic next-generation sequencing (mNGS) detected A. melanogenum in bronchoalveolar lavage fluid, which was confirmed by PCR-Sanger sequencing. Susceptibility thresholds for Aureobasidium have not been established, and the optimal treatment requires further investigation. This case highlights that A. melanogenum infection should be considered even when lung lesions cannot be diagnosed by conventional methods. mNGS demonstrates potential advantages in detecting this pathogen, underscoring its value in diagnosing such rare fungal pulmonary infections.