Bronchoscopic local instillation of amphotericin B deoxycholate as adjunctive therapy for pulmonary mucormycosis with inadequate response to posaconazole: a retrospective case series.

Background: Pulmonary mucormycosis is a life-threatening invasive fungal infection, most often affecting immunocompromised patients. Liposomal amphotericin B is the preferred first-line therapy, but amphotericin B formulations may be poorly tolerated. When endobronchial obstruction and tissue necrosis are present, pulmonary lesions may progress despite systemic antifungal therapy. Methods: We retrospectively reviewed patients with documented pulmonary mucormycosis who received posaconazole-based therapy at the First Affiliated Hospital, Zhejiang University School of Medicine between May 2019 and December 2022. Patients who showed clinical deterioration, radiologic progression, or no meaningful radiologic improvement during posaconazole-based therapy and then underwent bronchoscopic airway clearance followed by local instillation of amphotericin B deoxycholate were included. Results: Nineteen patients received posaconazole-based antifungal therapy during the study period, and five met the eligibility criteria. Their mean age was 56.2 ± 3.96 years; four had major underlying conditions, including hematologic malignancy or destroyed lung after tuberculosis, and one had a previous history of pulmonary and sinonasal fungal disease. Diagnostic evidence included mNGS, fungal fluorescence staining, bronchoalveolar lavage findings, and/or histopathology. Bronchoscopy identified obstructing mucus plugs, purulent secretions, necrotic material, or segmental narrowing in all patients. Amphotericin B deoxycholate was locally instilled at 7.5-15 mg in 10-15 ml diluent for 2-3 sessions while posaconazole was continued. No treatment-limiting cough, clinically significant oxygen desaturation, hemoptysis, bronchospasm, or new hepatic or renal dysfunction related to the local procedure was documented. Follow-up CT showed partial absorption or shrinkage of the dominant pulmonary lesions in all five patients, and none required surgical resection. Conclusions: In this small retrospective case series, bronchoscopic airway clearance plus local instillation of amphotericin B deoxycholate appeared feasible and well tolerated as an adjunctive salvage approach for selected patients with pulmonary mucormycosis and inadequate response to posaconazole. Because mechanical clearance and local drug delivery were inseparable in this study, the efficacy of local amphotericin B cannot be established from these data alone.