Alteplase for Percutaneous Treatment of Loculated Abdominopelvic Abscesses

Inclusion Criteria: * Ability to provide written informed consent and comply with study assessments for the full duration of the study. * Age \> 18 years * Adult, non-gravid patients with loculated abdominopelvic abscesses immediately after percutaneous drainage will be eligible to participate. A loculated abscess is defined as an abscess whose contents cannot be completely drained at the time of initial catheter placement as documented on CT. Exclusion Criteria: * Active internal bleeding, involving intracranial and retroperitoneal sites, or the gastrointestinal, genitourinary, or respiratory tracts * History of stroke within 6 months * Uncorrectable bleeding diathesis (INR \> 1.3 despite therapy) * Recent intracranial or intraspinal surgery or trauma * Pregnancy (positive pregnancy test) * Pancreatic abscesses * Any other condition that the investigator believes would pose a significant hazard to the subject if the investigational therapy were initiated * Participation in another simultaneous medical investigation or trial * Participation in another clinical investigation within previous 30 days of catheter placement * Prior enrollment in the study * Known allergy to Alteplase or any of its components