“Currently, the most common etiologies of pyogenic liver abscesses include biliary tract manipulation, diverticular disease, inflammatory bowel disease, and systemic infections such as bacterial endocarditis. Rarely, endoscopic retrograde cholangiography for ascending cholangitis or the management of biliary strictures may result in liver abscess. Patients with contrast material injected proximal to undrained strictures are at high risk.”  (Schwartz’s Principles of Surgery, 8th ed.)