Risk Factors, Management, and Outcomes of Pyogenic Liver Abscess in a US Safety Net Hospital.

Background: The causes and management of pyogenic liver abscess (PLA) have undergone multiple changes over the past decades. It is a relatively rare disease in the USA, and its incidence rate in the USA is increasing. The last US community hospital experience of PLA was published in 2005. We performed a retrospective study of patients admitted with PLA to an urban safety net hospital.

Aims: To ascertain risk factors, management approaches, and outcomes of PLA.

Methods: Electronic medical record was queried for diagnosis codes related to PLA during the years 2009-2018. Clinical information was compiled in an electronic database which was later analyzed. Main study outcomes were in-hospital mortality, 30-day readmission rate, and intensive care utilization rate.

Results: A total of 77 patients with PLA were admitted in the study period. Most common risk factors were diabetes mellitus (23.4%), previous liver surgery (20.7%), and hepatic malignancy (16.9%). 89% of patients were treated with percutaneous drainage or aspiration, and surgical drainage was reserved for other with other indications for laparotomy. In-hospital mortality, 30-day readmission, and intensive care utilization rates were 2.6%, 7% and 22%, respectively. Median length of stay was 11 days (inter-quartile range 7). Rate of antimicrobial resistance in abscess fluid cultures was 40%; 13 cases of Klebsiella pneumoniae liver abscess were noted in our cohort, most of whom were Hispanic or Asian.

Conclusions: PLA was principally managed by percutaneous drainage or aspiration with good outcomes. Further studies investigating the racial predilection of K. pneumoniae liver abscesses could reveal clues to its pathogenesis.