Neutrophils in pleural infection: untapped potential for targeted therapeutics

Pleural infections have been known since ancient times and remain a clinical challenge in the present day. These infections affect more than 80 000 people each year in the USA and UK combined [1], and are associated with a significant treatment burden, long hospital stays of, on average, 15 days, and inpatient mortality of 14.9% [2]. The recommendations for treatment advise prompt drainage of infected fluid along with initiation of broad-spectrum antibiotics to cover the wide range of causative organisms that may be present. The British Thoracic Society guidelines recommend treatment with a combination of DNase and tissue plasminogen activator if chest tube drainage does not clear the infected fluid completely; however, there is a potential risk of bleeding, and this may not be a suitable option for all patients. Surgical treatment is required in 16–27% of patients due to a failure of medical treatment [3]. Therefore, there is an unmet need for the development of new, targeted treatments for pleural infection which will be aided by a deeper understanding of the biological processes behind this challenging disease.