TY - JOUR T1 - Lung abscess or empyema? Taking a closer look JF - Thorax JO - Thorax SP - 887 LP - 889 DO - 10.1136/thoraxjnl-2018-211604 VL - 73 IS - 9 AU - Maged Hassan AU - Rachelle Asciak AU - Rana Rizk AU - Hany Shaarawy AU - Fergus V Gleeson AU - Najib M Rahman Y1 - 2018/09/01 UR - http://thorax.bmj.com/content/73/9/887.abstract N2 - Maged Hassan (MH): I would like to present three cases of patients who presented with symptoms of lower respiratory tract infection, fever and cough productive of small amount of sputum. The three patients had complained of symptoms for at least 2 weeks before presentation. The chest X-rays showed large encysted collections (figure 1A) which required chest CT to delineate the source of the abnormality. The CT studies (case 1: figure 1B, C; case 2: figure 2A and case 3: figure 2C) caused prolonged discussion between the treating clinicians with opinions divided on the nature of the lesion in each case being either an encysted empyema or a large peripheral lung abscess. Clinically, the differentiation between empyema and lung abscess was important because empyema is treated with tube drainage which is only resorted to in limited situations in lung abscess with the attendant risk of creating a bronchopleural fistula or extending the infection to the pleura.Figure 1 Case 1. (A) Chest X-ray shows right side cavity with air-fluid level. (B) Chest CT with contrast, axial cut, shows right side spherical lesion with air-fluid level causing lung collapse at the hilum (hollow arrow). Note pleural enhancement and extrapleural fat hypertrophy (arrowheads). (C) Chest CT, coronal reconstruction in lung window shows the acute angle the lesion makes with the chest wall and the pushed distorted airways proximal to the lesion (hollow arrow). (D) Thoracic ultrasound shows multiple hyperechoic shadows inside an echogenic collection. (E) Follow chest X-ray 48 hours after chest tube insertion (seen in situ) shows lung re-expansion.Figure 2 Case 2. (A) Baseline CT chest with contrast, coronal cut showing large left collection that is making an acute angle with chest wall (arrow) and uniformly thin wall with smooth inner margins (hollow arrows). (B) Chest X-ray following chest tube removal. Note thickened visceral pleura (hollow arrows). … ER -