Risk of infections subsequent to pyogenic liver abscess: a nationwide population-based study

This nationwide study aimed to provide risk estimates for a panel of infections subsequent to pyogenic liver abscesses (PLA) in Taiwan. In this study, we selected 12 050 patients diagnosed with PLA as our study cohort and 60 250 non-PLA patients as our comparison cohort. We individually tracked each subject for a 1-year period beginning with their index date to identify those who were subsequently diagnosed with any of the following infections: pneumonia, endophthalmitis, septic pulmonary embolism, pulmonary abscess, pleural empyema, meningitis, abscess of prostate, renal and perinephric abscess, epidural spinal abscess, osteomyelitis, necrotizing fasciitis, splenic abscess, psoas abscess and infectious endocarditis. We found that during the 1-year follow-up period, the subjects with PLA had a consistently higher incidence of all types of infections than comparison subjects. In particular, compared with subjects without PLA, the adjusted hazard ratios (HR) of pulmonary abscess, pleural empyema, renal and perinephric abscess, epidural spinal abscess and splenic abscess were 26.71, 18.56, 43.21, 51.32 and 126.51, respectively. We further analysed the HR of extra-hepatic Klebsiella pneumoniae infections among patients with PLA caused by K. pneumoniae. We found that the HR was higher for 12 of the 15 analysed extra-hepatic infections after restricting the analysis to only infections with K. pneumoniae aetiologies.