Abstract
Drowning-associated pneumonia often involves multiple types of pathogens, including Aeromonas hydrophila, Legionella spp., and fungi. We report the case of an 82-year-old man who developed a rare combined infection with these three organisms after freshwater drowning. Initial therapy for typical aspiration pneumonia was ineffective. Although A. hydrophila and Legionella pneumophila were subsequently identified and targeted, the patient's condition failed to improve. While chest computed tomography on the 11th day of hospitalization revealed worsening infiltrates and new cavity lesions, bronchoscopy was delayed until Day 13 due to circulatory instability. Subsequently, Aspergillus fumigatus was identified from bronchial lavage. Despite starting targeted antimicrobial and antifungal therapy late, the patient died on Day 21. This case highlights that in freshwater drowning, immediate broad-spectrum empirical treatment covering high-risk environmental bacteria and Legionella is essential. Furthermore, if initial therapy is ineffective or radiological progression occurs, early bronchoscopy must be performed to identify secondary or opportunistic pathogens, including Aspergillus or other fungi to prevent deadly delays in diagnosis.