Klebsiella Pneumoniae Liver Abscess Syndrome – A Challenge for Contrast-Enhanced Ultrasound

Invasive liver abscess syndrome (ILAS) is caused by strains of hypervirulent Klebsiella pneumoniae (hvKp) and has emerged as the leading cause of liver abscesses in immuno-competent patients (L.K. Siu et al. Lancet Infect Dis 2012; 12: 881–87). ILAS is frequently associated with metastatic spread including the eyes, lungs, and the central nervous system. The morbidity and mortality of affected patients are increased compared to liver abscesses of other origin, especially in cases with concomitant diabetes mellitus (J. E. Choby et al. J Intern Med 2020; 287(3): 283–300). Immediate diagnosis and early intervention are essential for an optimal outcome. Therefore, ultrasound plays a crucial role if hvKp is suspected. However, experience with the characteristics of such abscesses on contrast-enhanced ultrasound (CEUS) is very limited.