A 57-year-old female with a history of hypothyroidism, hyperlipidemia, and glaucoma presented to the interventional pulmonology (IP) clinic for evaluation of lung nodules found incidentally on chest imaging for evaluation of chronic cough. Her dry cough had persisted for 4 months, and computed-tomography (CT) of the chest demonstrated right lower lobe clusters of noncalcified, solid nodules, largest measuring 10 x 15 mm, with an enlarged subcarinal lymph node (LN) measuring 1.4 x 2.8 cm (Figure 1). She denied fever, chills, anorexia, night sweats, or weight loss. She was a never smoker and had no identifiable environmental or occupational exposures. Her physical examination and initial blood work including complete blood count (CBC) and chemistry were unremarkable. The decision was made to pursue biopsy of the enlarged subcarinal LN to test for old granulomatous disease, in particular, histoplasmosis. Under conscious sedation, endobronchial ultrasound (BF-UC180F bronchoscope) was advanced orally and transbronchial needle biopsy (EBUS-TBNA) of station 7 was performed. A total of 4 biopsies were obtained using a 21G needle (ViziShot Olympus). Rapid on-site evaluation (ROSE) commented on excessive necrosis from each pass. Cultures including bacterial, fungal, and acid-fast bacteria (AFB) were negative. Final cytology was negative for infectious and malignant etiologies.
Ten days later, she presented to the Emergency Room with complaints of a low-grade fever, shortness of breath, and sharp and posterior right-sided chest pain which worsened since the procedure. Her vital signs and physical examination were unremarkable. Initial laboratory work demonstrated a mild leukocytosis with left shift (12.5 x 109/L, 76.9% neutrophils), and CT chest was significant for a large subcarinal mass measuring 5.5 x 2.6 cm causing mass effect on adjacent vessels and esophagus (Figure 1). Following an interdisciplinary discussion with IP, interventional radiology, and thoracic surgery, the decision was to proceed with mediastinoscopy for further evaluation. Intraoperatively, the subcarinal mass had thick fluid inside which grew Propionibacterium acnes (P. acnes). Fungal cultures, KOH stain, and AFB stain and culture were negative. Final histopathology showed fibroadipose tissue with fibrin, fat necrosis, and chronic inflammation consistent with abscess. There was no evidence of malignancy.
Two weeks later, the patient continued to have a cough and repeat imaging showed a new 7.7 x 3.9 x 8.0 cm irregular, heterogeneous, air-containing mass in the superior medial right lower lobe concerning a lung abscess (Figure 1). The patient was admitted to hospital and begun on IV vancomycin and piperacillin-tazobactam and discharged on IV ampicillin-sulbactam. She was followed up in both IP and infectious diseases clinic 18 days later with significant improvement in symptoms and imaging. She was transitioned to oral amoxicillin-clavulanate for an additional month. Follow-up imaging after completion of antibiotics demonstrated near-resolution of the abscess (Figure 1).