Spontaneous empyema necessitatis caused by Aspergillus fumigatus in an immunocompetent patient

A 60-year-old woman presented with fever, chest wall pain and mild dyspnoea for days. The woman sought medical attention in the outpatient department. She stated that she had been healthy in the past and had no history of diabetes, hypertension or other disease. However, she had been a vegetarian for decades. She had no gross lesion in the chest wall and she also denied any trauma as well as travel history. Auscultation of the lung showed some rales and decreased breath sounds in right lower lung fields. The patient was then admitted for relevant studies under the impression of pneumonia with parapneumonic effusion on the right side. Laboratory data showed leukocytosis (18300 cells/ul), elevated C-reactive protein, and abnormally elevated serum level of creatinine (2.0 mg/ dl). Chest radiograph showed pleural effusion in right lower lung field and interlobar space. Lateral view showed the haziness was mainly located in anterior aspect (Figures 1a and 1b). Subsequent CT scan of the chest showed pneumonic consolidation in the right middle lobe, loculated effusion near mediastinum and some effusions in the dependent pleural cavity (Figure 2a). Figure 2b also showed abscess formation in lung parenchyma. Chest tapping yielded minimal purulent effusion. She was treated for a short course of antibiotics emperically, including cephalosporin of second generation and amyloglycoside because there was no definite pathogen cultured from pleural effusion as well as sputum. Her symptoms of fever, dyspnoea and chest wall pain improved after a 2-week antibiotic treatment and she was discharged home. She came to the outpatient department once amonth for follow-up and recovered well. Eight months later, the patient presented fever, up to 39 ̊C, dyspnoea and chest pain. She was brought to the emergency room. Physical examination revealed fever, tachypnea, and pus discharge from the right lower chest wall in anterior aspect. The surrounding skin was also erythematous. She was admitted again. Subsequent CT scan of the chest showed rib erosion, cartilage destruction and necrosis both inside and outside of the chest wall (Figure 3a). Abscess formation was also seen in area of low density in the chest wall on CTscan of the chest (Figure 3b). Therewas no effusion in the dependent portion of the pleural cavity. Due to severe infection, the patient underwent anterior thoracotomy to open the pleural space. On skin incision, a lot of purulent discharge gushed out. There was one 12x10 cm residual space in the pleural space and chest wall due to collapsed right middle lobe and evacuation of the purulent fluids as well as necrotic soft tissues. The opened pleural space was not communicating to other portion of the pleural space because of dense fibrosis. Lung tissue did not expand adequately to fill the dead space. The space was packed with wet gauzes and prepared for later wound closure. Two destructed ribs were removed and a small portion of the fragile costal cartilages was removed. Debridement of the soft tissues was also performed in the same time. DECLARATIONS