Outpatient Treatment with Isavuconazole for Recurrent Chronic Cavitary Pulmonary Aspergillosis in a Residual Post-Lobectomy Cavity: A Case Report

Background: Chronic pulmonary aspergillosis (CPA) is a slowly progressive pulmonary fungal disease, predominantly caused by Aspergillus fumigatus, which develops in patients with pre-existing structural lung abnormalities. Chronic cavitary pulmonary aspergillosis (CCPA), the most common form of CPA, is characterized by one or more pulmonary cavities, with or without intracavitary fungal balls (aspergillomas), and requires prolonged oral triazole therapy. Long-term treatment may be limited by adverse events, drug–drug interactions, and the need for therapeutic drug monitoring with conventional azoles. Case Presentation: A 69-year-old former smoker with a history of breast cancer and right upper lobectomy for pulmonary adenocarcinoma presented with fever, productive cough, hyporexia, sarcopenia, and an unintentional 6 kg weight loss over three months. Two years earlier, she had undergone atypical pulmonary resection for an Aspergillus fumigatus aspergilloma and had been treated with amphotericin B followed by voriconazole for six months. HRCT revealed a recurrent intracavitary fungal lesion within a residual post-surgical cavity with extensive inflammatory consolidation. Bronchoalveolar lavage demonstrated a positive galactomannan index (4.74) and septate fungal hyphae on cytology, supporting the diagnosis of recurrent CCPA. Treatment with oral isavuconazole resulted in clinical recovery, weight gain, and complete radiological resolution after six months, without treatment-related adverse events or QTc abnormalities. Conclusions: This case highlights the successful outpatient management of CCPA developing within a persistent post-lobectomy cavity despite previous surgical resection and antifungal therapy. The favourable clinical response, excellent tolerability, and absence of treatment-related toxicity support the growing evidence that isavuconazole may represent a valuable therapeutic option for selected patients with recurrent CCPA.