Fatal Tracheal and Bronchial Destruction Due to Pulmonary Mucormycosis in a 20-Year-Old with Diabetic Ketoacidosis.

Pulmonary mucormycosis is a rare and aggressive invasive fungal infection that predominantly affects immunocompromised individuals, such as those with diabetes mellitus or those undergoing immunosuppressive therapy. This case describes a severe instance of pulmonary mucormycosis resulting in progressive tracheal wall destruction in a young, previously healthy male. A 20-year-old male with a denied history of diabetes mellitus was admitted to a local hospital with abdominal pain for 9 days and diagnosed with acute pancreatitis and diabetic ketoacidosis (DKA). During his stay at the local hospital the patient developed respiratory distress and was transferred to our hospital. Although initially given non-invasive respiratory support and broad-spectrum antibiotics, the patient's condition deteriorated and invasive mechanical ventilation and VV-ECMO were given. Bronchoalveolar lavage fluid (BALF) next-generation sequencing (mNGS) identified Rhizopus species, confirming pulmonary mucormycosis. Aggressive antifungal therapy with amphotericin B was administered, followed by the addition of isavuconazole, but the patient's lesions continued to expand, ultimately leading to fatal tracheal and bronchial wall disruption and subsequent haemorrhage. This case emphasizes the rapid progression and extensive tissue destruction characteristics of pulmonary mucormycosis. Early diagnosis and treatment, especially simultaneous antifungal therapy and appropriate surgical intervention, are crucial for improving the prognosis of such severe cases.