Case Report: Pulmonary brucellosis presenting as multiple cavitary lung lesions on imaging

Pulmonary brucellosis is a rare focal manifestation of human brucellosis with non-specific clinical features. Predominant imaging findings include pneumonia, pleural effusion, pulmonary nodules, abscesses, and interstitial changes. Multiple cavitary lesions are exceptionally rare. Herein, we report a case of bilateral multiple pulmonary cavities in a 76-year-old man with a 2-year history of intermittent cough, sputum production, and progressive dyspnea that acutely worsened 10 days prior to admission with intermittent fever, anorexia, and fatigue. Chest computed tomography (CT) revealed bilateral upper lobe irregular mass-like opacities and multiple nodules with heterogeneous density, punctate calcifications, and cavitation; multiple microcavitations in the right middle and lower lobes and the left lower lobe; and enlarged, calcified hilar and mediastinal lymph nodes. Metagenomic next-generation sequencing of bronchoalveolar lavage fluid identified Brucella species, which was confirmed by positive serology. After 3 days of doxycycline (0.1 g bid po) and rifampicin (0.6 g qd po), followed by 140 days of doxycycline (0.1 g bid po), rifapentine (0.6 g biw po), and levofloxacin (0.5 g qd po), along with silibinin meglumine tablets 0.1 g tid po for hepatoprotective therapy, the patient became afebrile with significant symptomatic improvement. Repeat chest CT demonstrated reduction in the right upper lobe consolidation/cavity and left upper lobe consolidation, resolution of the right lower lobe cavity, and complete resolution of the microcavitations. This case underscores that pulmonary brucellosis should be considered in the differential diagnosis of cavitary lung lesions in patients with livestock exposure and that prolonged combination antibiotic therapy can achieve favorable clinical and radiological outcomes.