The aim of this study was to assess the efficacy of the modified regimen short duration intrapleural 16mg alteplase (Actilyse, Boehringer Ingelheim) with 5mg DNase (Pulmozyme Hoffmann-La Roche Ltd) in patients with pleural infection.

The regimen 10 mg alteplase and 5 mg DNase twice daily that was used in MIST-2 trial is still an empiric choice. The rationale of using 3 doses of 16 mg alteplase dose (with supplementary 5 mg DNase) in our study was governed by the formulation of alteplase in our country (50 mg per ampoule); hence, it is best used within 24 hours following reconstitution as its biochemical stability up to 24 hours as assessed by in vitro clot lysis assays.

Inclusion Criteria:

• adult patient with age more than 17 year old
• evidence of complex parapneumonic effusion or empyema; with poor pleural fluid drainage of ≤150 mL after 24 hours of insertion of chest drain
• clinical evidence of infection such as fever and or elevated C-reactive protein (CRP) or white-cell count
• complex pleural effusion proven by ultrasound
• pleural fluid analysis that fulfilled at least one of the characteristics: frank pus, exudative nature (according to light's criteria), gram stain or culture positive, lactate dehydrogenase (LDH) > 1000 U/L, pH < 7.2 and/or glucose level < 3.3mmol/L

Exclusion Criteria:

• known allergy to pulmozyme or alteplase
• acute stroke, active bleeding diathesis
• major surgery in past 5 days
• previous pneumonectomy on the infected side
• bronchopleural fistula
• pregnancy
• coagulopathy (INR > 2, APTT >100, platelet count < 50,000 cells)

The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.

The radiologists were blinded to patient identity and intervention timing