Bacterial abscess of the liver is relatively rare; however, it has been described since the time of Hippocrates (400 BCE), with the first published review by Bright appearing in 1936. In 1938, Ochsner's classic review heralded surgical drainage as the definitive therapy; however, despite the more aggressive approach to treatment, the mortality remained at 60-80%.
The development of new radiologic techniques, the improvement in microbiologic identification, and the advancement of drainage techniques, as well as improved supportive care, have reduced mortality to 5-30%; yet, the prevalence of liver abscess has remained relatively unchanged. Untreated, this infection remains uniformly fatal.
The three major forms of liver abscess, classified by etiology, are as follows:
Pyogenic abscess, which is most often polymicrobial, accounts for 80% of hepatic abscess cases in the United States
Amebic abscess due to Entamoeba histolytica accounts for 10% of cases 
Fungal abscess, most often due to Candida species, accounts for fewer than 10% of cases