Hepatobiliary infections.
The major hepatobiliary infections (excluding the viral hepatitides) include amebic and pyogenic liver abscess and cholangitis. Little new information has been published in the area of cholangitis during the last several years. In contrast, the clinical presentation and management of liver abscess have evolved considerably, not only in the last several years but also during a more extended period spanning the last two decades. In the United States, amebic liver abscess occurs largely in individuals from endemic areas or in those traveling to endemic areas. Recent data suggest that patients with human immunodeficiency virus (HIV) infection are at an increased incidence of amebic liver abscess. New serologic tests and molecular techniques are being added to the diagnostic armamentarium for amebic liver abscess. In most cases, amebic liver abscess is associated with an excellent prognosis (up to 100% survival) if properly managed. Pyogenic liver abscess, although commonly occurring in patients with known biliary tract disease, is often cryptogenic in origin (ie, no clear causal factor can be identified) or often is caused by underlying medical disorders. An emerging population of patients with pyogenic liver abscess includes those with complications of aggressive interventions (hepatic chemoembolization, cryoablation, liver transplantation). Pyogenic liver abscess was predominantly managed by surgical methods up until the early 1980s, but almost entirely has changed to being managed by interventional techniques; in 2000, this trend has continued. In contrast to amebic liver abscess, pyogenic liver abscess is associated with greater morbidity and mortality, ostensibly caused by the severity of the underlying disease in many patients. However, it should be emphasized that the prognosis of patients with pyogenic liver abscess, who do not have underlying comorbid conditions, is excellent.