Moreover, there is activation of the coagulation selleckchem cascade and depressed fibrinolytic activity, which leads to the formation of septations as a result of fibrin deposition.8 A fibrino-purulent collection follows and is often associated with a paucity

of organisms – as few as 25–30% of empyemas are actually culture positive.7 The organising stage follows as fibroblasts create a solid fibrous pleural peel replacing the soft fibrin. This can prevent the re-expansion of the lung and create a persistent area of pleural thickening.9 What was our therapeutic intervention? Intrapleural fibrinolytic drugs (streptokinase 250 000 IU twice daily for 3 days) were given. In the UK up to 20% of empyema patients come to surgery due to failed catheter drainage and, overall, 20% of patients with empyema die.10 Intravenous antibiotics and chest tube drainage are the first line treatments. However, as outlined above, infected fluid can become septated and hence resist drainage. A meta-analysis from the Cochrane library11 evaluated four trials12, 13, 14 and 15 and concluded that fibrinolytics reduce hospital stay, shorten the period of fever, produce PI3K inhibitor radiological improvement, and reduce the incidence of treatment failure (defined as death). However MIST 1, a large randomised trial of intrapleural

streptokinase, failed to show any benefit in terms of mortality, rates of surgery, radiographic outcomes, or length of the hospital stay.16 However, all infected effusions were included in this study from many centres with varying experience in their management and Phospholipase D1 it is argued that streptokinase would not work in the effusions in the late organised stage with hard peels.17 The patients were much older and had many more co-morbidities than

in the previous trials. The effusions were also only treated with smaller chest tubes without image guidance. Our centre has considerable experience managing complicated parapenumonic effusions utilising image-guided drainage and intrapleural streptokinase. Streptokinase is adhesiolytic and complexes of streptokinase with human plasminogen can hydrolytically activate other unbound plasminogen to produce plasmin which breaks fibrin down. However, it is not bactericidal and does not reduce viscosity of pus which has a high DNA content from degranulated cells. It is plausible that a combination of agents that reduce pus viscosity (e.g., DNase) and those that break down loculations may be necessary to enhance pus drainage. Rahman et al.18 found that intrapleural tissue plasminogen activator and DNase therapy improved fluid drainage in patients with pleural infection and reduced the frequency of surgical referral and the duration of the hospital stay. This was a study of 201 patients with pleural infection who received double placebo, intrapleural tissue plasminogen activator (t-PA) and DNase, t-PA and placebo, or DNase and placebo for 3 days.