Failure To Perform Repeat Ascitic Tap At 48hr Has Poorer Outcomes In Spontaneous Bacterial Peritonitis

IntroductionIn patients with Spontaneous Bacterial Peritonitis (SBP), acute kidney injury and high serum bilirubin are known predictors of in-hospital mortality. The effect of patient management on mortality is unknown. This study aims to identify predictors of in-hospital mortality, accounting for management of patients with SBP, according to EASL Clinical Practice Guidelines published in 2010.MethodsClinico-demographic, biochemical and microbiological data from patients presenting between 2014 and 2019, with a first episode of SBP (ascitic fluid neutrophil count > 250 cell/cm³) were reviewed. The primary endpoint was in-hospital mortality. Logistic regression was used to identify predictors of outcome.ResultsOverall, 130 patients (median [IQR] age 58 [51 - 66] yr; 65% male; aetiology: alcohol 36%; MELD score 18 [13 - 25]) were included. Infection was nosocomial in 49%; 35 had concomitant bacteraemia (n = 14), respiratory (n = 16) or urinary infections (n = 9). Pathogens were identified in 57 (44%) patients within 42 [36 – 50] hr post initial ascitic tap; antibiotic sensitivities were available by 53 [49 – 62] hr. Multidrug resistant pathogens (MDRP) were identified in 12 (21%) of the 57; 10 of the 12 showed < 25% reduction in ascitic neutrophil count at 48 hours. There were 29 (22.3%) in-hospital deaths; the median time to death was 6 [1 – 8] days. A total of 31 (24%) patients were admitted to ITU and one-third (n = 13) of this cohort died. One patient underwent liver transplantation. On univariate analysis, admission MELD, peripheral white cell count, INR, serum creatinine, failure to culture a pathogen, failure to perform a 48-hour ascitic tap and development of acute kidney injury were predictors of in-hospital mortality. Age, nosocomial infection or the presence of a MDRP were not. Failure to perform a 48-hour ascitic tap (OR [95% CI] = 11.2 [2.9 – 43.7], p < 0.01), acute kidney injury (9.1 [2.0 – 41.5], p < 0.01) and MELD score (1.2 [1.1 – 1.3], p < 0.01) retained significance on multivariate analysis.ConclusionsIn-hospital mortality associated with SPB is unacceptably high at 22%. Failure to repeat the ascitic tap at 48 hours, a recommendation based solely on expert opinion in the EASL guideline, was a highly significant prognostic factor allowing early identification of patients who fail to respond to empirical antibiotic therapy. This requirement should now become recommended practice.