The Application Value of Metagenomic Next-generation Sequencing in the Diagnosis of Pulmonary Mucormycosis

Background Although pulmonary mucormycosis is rare, it is highly invasive and carries a significant mortality rate. Due to its nonspecific clinical manifestations, it is often misdiagnosed as other invasive fungal diseases. Metagenomic next-generation sequencing is a rapid, precise, and comprehensive method for pathogen detection, showing great potential in the early diagnosis of pulmonary mucormycosis. It provides clinicians with faster and more accurate etiological information, thereby improving patient outcomes and reducing mortality rates. Methods This study retrospectively analyzed the clinical data of 14 patients diagnosed with pulmonary mucormycosis between 1/6/2021 and 30/6/2024. Results Males accounted for 57.14% of the cases. Diabetes mellitus was present in 12 patients (85.71%, 12/14), and fever was observed in 12 patients (85.71%, 12/14). The 14 patients were categorized as confirmed cases (4 cases), probable cases (4 cases), and possible cases (6 cases). Two patients (14.29%, 2/14) were diagnosed with disseminated mucormycosis. Chest Computed Tomography scans revealed cavities in half of the patients (50.00%, 7/14). Fungal hyphae were identified in 3 out of 4 histopathological examinations. mNGS detected Mucorales pathogens in 100% of cases, significantly outperforming the positive rates of the 1,3-β-D-glucan test test (35.71%, 5/14), Galactomannan test test (42.86%, 6/14), histopathology (75.00%, 3/4), and fungal culture (28.57%). Additionally, mNGS identified bacterial and viral co-infections, with 11 patients diagnosed as having mixed infections. All patients received timely and targeted treatment adjustments, resulting in 9 patients improving and being discharged, 2 patients being transferred to higher-level hospitals, and 2 patients discontinuing treatment. The 90-day follow-up revealed a mortality rate of 28.51%. Conclusions Metagenomic next-generation sequencing can serve as an important complement to traditional diagnostic methods, enabling rapid and accurate differentiation of Mucorales from other fungi. This allows patients to receive timely and targeted antifungal therapy, playing a critical role in early intervention and improving prognosis.