Polycystic liver disease is the most common extrarenal manifestation of autosomal dominant polycystic kidney disease. Hepatic cysts often are multiple, and in renal transplant recipients, occult infection with or without concurrent kidney cyst infection is a frequent cause of abdominal pain and fever and may require long-term antibiotic use and hospitalization. Rupture and bleeding of hepatic cysts into the peritoneum or viscera are infrequent complications that have been reported. Identification of a single culprit lesion that could be targeted for surgical intervention often is difficult because such imaging studies as computed tomographic scans, magnetic resonance images, or radionuclide-tagged white cell scans often show several inflamed cysts that can persist over several subsequent scans. Treatment may require surgical intervention. Eradication of infection and wound healing also is made difficult by concomitant immunosuppression in renal transplant recipients. We present the case of a renal transplant recipient with an infected dominant polycystic liver cyst that ruptured into the pericardium, leading to tamponade.