We described the case of a 49-year-old man with a 1-year history of intermittent cough and sputum production who had worsened over the last 4 days with fever and right chest pain. The patient recently had a history of unexplained weight loss of 5 kg. He has smoked 20 cigarettes per day since the age of 19. The patient had periodontitis and tooth loss. The patient had no history of travel or tuberculosis exposure and no food or drug allergies.
On admission, his temperature was 37.9 C, pulse rate 81 beats/min, respiratory rate 22 breaths/min, blood pressure 132/80 mmHg, and oxygen saturation 95% on room air.
Pulmonary percussion found dullness in the right lower lung, and pulmonary auscultation revealed decreased breath sounds in the right lower lung. The remaining physical examination was normal.
The laboratory findings were as follows: white blood cell (WBC) count 22.98 x 109/L with 85.5% segmented neutrophils, 7.6% lymphocytes, neutrophil count 19.9 x 109/L, and lymphocyte count 1.76 x 109/L, and his ultrasensitive C-reactive protein (hs-CRP) was 248.56 mg/L (normal range 0-5 mg/L). Serum tumor marker screening showed a slightly elevated neuron-specific enolase (NSE) of 17.05 ng/ml (normal range <16.3 ng/ml). The squamous cell carcinoma antigen (SCCA), cytokeratin-19-fragment (CYFRA21-1) and carcinoembryonic antigen (CEA) levels were normal. The other laboratory test results were normal. Chest computed tomography (CT) revealed an irregular mass in the right middle lobe of the lung near the interlobar fissure with right atelectasis and thickening of the right pleura with encapsulated effusion and pneumatosis (Figure 1A). Thoracentesis and catheter drainage were performed immediately after chest ultrasound confirmed pleural effusion. Analysis of the drained purulent fluid suggested an exudative process [fluid protein 54.9 g/L, serum protein 69.8 g/L (normal: 65-85 g/L), fluid lactate dehydrogenase 3,014 U/L, serum lactate dehydrogenase 220 U/L (normal 120.0-250.0 U/L)]. Other pleural fluid analysis showed WBC 3,800/muL with 80% neutrophils, fluid glucose 0 mmol/L, and fluid adenosine deaminase 81.8 U/L. Pleural fluid smear, Gram staining, bacterial culture, acid-fast bacilli culture and smear, and cytology were all negative. A blood culture was also negative. Empyema was diagnosed. He received intravenous imipenem/cilastatin 1.0 g once every 8 h. After repeated pleural effusion drainage and anti-infective treatment for 3 weeks, re-examination of lung CT showed no significant change in the amount of pleural effusion (Figure 1B).
The patient requested to be discharged after his fever improved. Half a month after discharge, he was admitted to our hospital due to progressive worsening of cough and shortness of breath. On April 1, a contrast-enhanced CT scan showed uneven enhancement of the mass in the lateral segment of the right middle lobe, mediastinal lymphadenopathy with visible enhancement, and a right hydropneumothorax (Figure 1C). In addition, the laboratory test results included WBC 11.56 x 109/L, neutrophil ratio 71.84%, and CRP 219.35 mg/L. Ultrasound re-examination showed that there was a localized anechoic area of 5.3 cm x 7.7 cm x 3.4 cm in the right thoracic cavity, and he underwent pleural puncture and drainage again. The pleural drainage fluid was sent for NGS. The NGS results only detected Fusobacterium nucleatum. Subsequently, the patient underwent bronchoscopy. Fiberoptic bronchoscopy showed complete airway obstruction due to whitish endobronchial membranous lesions in the lateral segment of the right middle lobe (Figure 2A). A cauliflower-like mass was seen and biopsied after clamping the whitish endobronchial membranous lesions (Figure 2B). Histological examination of the biopsy specimens demonstrated a highly differentiated squamous cell carcinoma in the right lung (Figure 2C). He was finally diagnosed with empyema caused by Fusobacterium nucleatum and squamous cell carcinoma of the lung. The patient's cough and shortness of breath were improved after draining 1,800 ml pleural effusion for 3 days, and cefoperazone sodium/sulbactam sodium 3 g was given intravenously twice a day for 2 weeks. Repeat chest CT revealed absorption of the fluid and gas in the right pleural cavity (Figure 1D). Meanwhile, blood biochemical examination showed that infection indexes, such as white blood cells and CRP, had returned to normal. Regrettably, the patient refused antitumor therapy.
CT scan images. (A) Chest CT showed an irregular mass at the right middle lobe of the lung near the interlobar fissure with right atelectasis and encapsulated effusion and pneumatosis.