Successful Management of Refractory Pulmonary Mucormycosis Using Intracavitary Amphotericin B: A Case Report and Literature Review.

BACKGROUND Mucormycosis is a rapidly invasive, highly fatal infection typically affecting immunocompromised patients, such as those with diabetes, hematologic malignancies, or HIV. We report a case of pulmonary mucormycosis in a female patient in which initial systemic therapy failed. CT-guided intracavitary amphotericin B instillation was used as salvage therapy. This approach delivered high-dose antifungal medication directly to the infection site, leading to significant clinical and radiological improvement. CASE REPORT We report a case of pulmonary mucormycosis complicated with Klebsiella pneumoniae infection in a 51-year-old female patient who had a history of diabetes. This patient was admitted to the hospital for dyspnea, chest pain, and fever, and a chest CT on admission suggested multiple inflammatory lesions in both lungs (involving abscesses or fungi). Bronchoscopy revealed left upper-lobe suppurative inflammation. Initial bronchoalveolar lavage fluid (BALF) tests (smears, culture, GM, X-pert) were negative. Finally, the BALF was tested by targeted next-generation sequencing (tNGS), and the diagnosis of pulmonary mucormycosis co-infected with Klebsiella pneumoniae was confirmed. After 21 days of treatment with intravenous amphotericin B and posaconazole, lung nodules/cavities (Mucor) showed no improvement, suggesting inadequate local drug penetration. The patient was ultimately treated with combined local (CT-guided intrapulmonary amphotericin B injection and nebulization) and systemic (intravenous amphotericin B and posaconazole) antifungal therapy, resulting in partial resolution of pulmonary cavities on follow-up CT. CONCLUSIONS This case report presents an innovative management strategy for mucormycosis; combined local and systemic antifungal therapy achieved clinical improvement despite limited intracavitary injections, providing a potential therapeutic approach for this challenging infection.