Prognosis of liver abscess in the intensive care unit (POLAIR), a multicentre observational study.

Background: Liver abscess (LA) is a rare but potentially serious condition with a high mortality rate. Current epidemiological data of LA patients requiring intensive care unit (ICU) admission are limited.

Methods: This multicentre retrospective study included adults admitted to 24 ICUs in France between January 2010 and December 2020. Risk factors for mortality were identified by multivariate analysis. A propensity score was used to adjust for confounders related to the presence of portal vein thrombosis.

Results: 335 patients were enrolled. The median age was 66 years [53-73] and 68% were male. Commons comorbidities included diabetes (29.9%) and cancer or haematological disease. Septic shock was the main reason for admission (58%). The median SAPS2 score at ICU admission was 42 [31-53] and the SOFA score was 6 [3-9]. The putative origin of LA was biliary (31%), while 40% were cryptogenic. Most patients (60%) had a solitary LA, involving the right lobe (38.8%), with a median diameter of 67 mm [47-91]. Associated portal vein thrombosis (PVT) was present in 13.4% of cases. Microbiological documentation was obtained in 82% of patients, showing gram-negative bacilli (59.7%), mainly Escherichia coli (19.6%) and Klebsiella spp. (19.1%), and gram-positive cocci (29.6%), mainly Streptococcus spp. (17.1%). Drainage was performed in 62% of cases, 40% within 48 h. The median duration of antibiotic therapy was 35 days [21-42]. During hospitalisation, 62% of patients required vasopressors and 29% required mechanical ventilation. In-ICU mortality was 11.6%. Multivariate analysis showed that organ dysfunction illustrated by SOFA score (HR 3.45 [1.95-6.09], p < 0.001) and PVT (HR 3.14 [1.54-6.39], p = 0.001) were significant risk factors for mortality. Drainage was not associated with improved short-term survival (HR 1.22 [0.65-2.72], p = 0.52). In the population matched for PVT confounders, a higher sofa score was the only factor associated with mortality (HR 3.11 [1.76-5.49] IC95%, p = 0.001).

Conclusions: This multicentre study illustrates the severity of LA in French intensive care units and identifies organ dysfunction (SOFA score) and portal vein thrombosis as major risk factors for mortality. Prospective studies are needed to improve management strategies, as the survival benefit of drainage is unclear.