Pyogenic liver abscess

The diagnosis of pyogenic liver abscess (PLA) represents a challenge for physicians due to their association with multiple pre-existing conditions.

Its incidence varies between 2.3 and 17.59 per 100 000 inhabitants per year,1–3 and in hospitalised patients, it is 8–22 cases per 100 000 hospital admissions.4 Usually occurs in Caucasian men between 50 and 60 years old.5 Risk factors include diabetes mellitus, bacteraemia of non-hepatic origin, immunosuppression, cirrhosis and a history of solid organ transplantation or splenectomy.6–8

Those microorganisms commonly found are specified in table 1. Generally, they are polymicrobial, although single bacteria can be isolated and, in up to 30% of cases, no infectious agent is identified.9

Escherichia coli had been considered the bacterium responsible for the largest number of cases of pyogenic abscesses in the world;10–12 however, it has been found that in Asian countries Klebsiella pneumoniae is one of the main aetiologies,13–15 and its presentation is monomicrobial, usually generates severe clinical conditions due to the hypervirulence and is not related to hepatobiliary diseases.16 17 An invasive syndrome has then been described by serotypes K1 and K2 that are associated with bacteraemia, necrotising fasciitis, endophthalmitis, meningitis and cerebral asbcesses.8 18

PLA can also occur in fungal coinfection by Candida spp., which affects patients with haematological malignancies, and Cryptococcus spp., which has been found in immunosuppressed patients by the HIV, solid organ transplants and primary immunodeficiencies.8

The clinical manifestations are abdominal pain, fever, jaundice, weight loss and chills, similar to an unknown origin fever, sepsis and acute abdomen. The classic triad characterised by fever, jaundice and abdominal pain in the right hypochondrium is only present in 10% of patients; fever is the most frequent symptom, followed by abdominal pain that …