Introduction
Yersinia pseudotuberculosis is a facultative anaerobic, Gram-negative, motile, non-spore-forming bacillus, belonging to the family Yersiniaceae. Y. pseudotuberculosis is a rare zoonotic infection, which may be transmitted to humans through contact with infected animals or after ingestion of contaminated food or water.1 The most common manifestations of infection with Y. pseudotuberculosis in humans are enterocolitis, terminal ileitis and/or mesenteric lymphadenitis, initially often interpreted as acute appendicitis, therefore sometimes characterized as pseudoappendicitis.2
A pyogenic liver abscess (PLA) is pus-filled cavity within the liver due to a bacterial infection.3 The annual incidence of PLA has been reported between 1-7 cases per 100,000 in some Western Countries and higher among men than women4,5,6 , while higher rates have been reported in Taiwan (17.6 per 100,000) withKlebsiella pneumoniae as the primary pathogen.7The majority of PLA occurs in patients with pre-existing gastrointestinal or biliary disease and originates from hematogenous spread though the portal vein. The most common pathogens includeKlebsiella pneumoniae, Escherichia coli, Streptococcusanginosus -group, Enterococcus species and anaerobic bacteria such as Bacteroides species or Fusobacteriumspecies.3 But, in some cases, the etiologic microorganisms remain unidentified. This is particularly common, when abscess drainage is difficult and antibiotics are initiated before abscess puncture resulting in culture-negative PLA.8
Sepsis with Y. pseudotuberculosis is rare, but have been described in patients with underlying medical conditions such as diabetes mellitus, malignancy, iron overload, and liver disease.1,2 Though uncommon, infections with Y. pseudotuberculosis disseminated through the blood stream have been described, including hepatic9-14, splenic13,15 and pulmonary abscesses16, peritonitis2, myocarditis2, osteomyelitis17 and meningitis.2 Here, we describe the first Danish case of Y. pseudotuberculosis PLA in a patient with newly diagnosed diabetes mellitus.