Pyogenic Infection of Liver Secondary to Infection in the Portal Drainage Area.

This condition is a result of bacterial infection reaching the portal tracts from an infective lesion in the portal drainage area and producing periportal inflammation which may proceed to suppuration. These cases provide a diagnostic and therapeutic problem which it is the object of this paper to discuss. The types of lesion which may occur may be divided into two groups: (1) pylephlebitis, and (2) solitary pyogeniq liver abscess. It was emphasized by Eliason (1926) that the terms " pylephlebitis " and " pyogenic liver abscess " should not be used synonymously. Pylephlebitis is a septic thrombophlebitis of the portal vein or its branches. This condition may resolve with or without treatment or it may proceed to suppuration and abscess formation. Solitary liver abscess may result from infection reaching the liver by numerous routes. This paper is concerned only with those cases in which the route of infection is by the portal vein and the responsible organism is one of the pyogenic bacteria. Abscesses due to actinomycosis and amoebae are excluded. Pyogenic abscesses are probably secondary to pylephlebitis which has not been recognized and has resolved except for leaving an abscess in the liver. The essential feature of pylephlebitis is the presence of infected thrombi in the portal vein or its branches. A case of pyogenic abscess of the liver may not show this lesion, and the question then remains whether the path of spread from the primary fowus was by the portal venous system. The route by which the infection spread is especially open to question in those cases that have no demonstrable primary intra-abdominal infection. Rothenberg and Linder (1934) thought that infection from pharyngeal or cutaneous foci via the hepatic artery was a frequent cause, but were unable to prove this connexion. From a consideration of the post-mortem appearance of these abscesses Beaver (1931) concluded that they resulted from the entry into the portal blood-stream of multiple infected emboli or discrete masses of bacteria. Stokes (1960) reported a personal series of six cases and thought that the origin of infection in these cases was from the portal drainage area. He pointed out that the organisms causing these abscesses were of the type derived from the bowel. The Table gives the clinical and laboratory features of eight cases, and reports of three of these are presented and discussed.