Outcomes after hospitalisation with spontaneous bacterial peritonitis over a 13-year period: a retrospective cohort study

Goals Assess outcomes in patients with an index presentation of spontaneous bacterial peritonitis (SBP) over a 13-year period. Background SBP, a bacterial infection of ascites, has a poor prognosis. Study Retrospective cohort study assessing mortality (standardised to 32 months) and prognostic factors in patients with SBP during two periods: period 1 (June 2006 - November 2012) and period 2 (December 2012 - May 2019). Results The study included 178 patients followed-up for 11.6 (29.2) months. Mortality was high, with 12-, 24- and 32-month survival being 32%, 26% and 24% respectively. Inpatient mortality was 36%, mortality in those surviving hospitalisation being 62%. Serum creatinine at time of SBP diagnosis was an independent predictor of mortality at 32 months (hazard ratio (HR) 1.002, p=0.023) and inpatient mortality (HR 1.003, p=0.035). Positive ascitic fluid culture and ascitic fluid neutrophil count were independent predictors of 32-month (HR 1.679, p=0.008) and inpatient mortality (HR 1.0001, p=0.005) respectively. Patients in period 2 had lower ascitic fluid albumin (5.9 ± 3.3 g/L vs. 10.8 ± 5.4 g/L, p<0.001), higher ascitic fluid neutrophil count (815.0 cells/mm3 vs. 345.0 cells/mm3, p<0.001) and higher rates of hepatorenal syndrome-acute kidney injury (58% vs. 35%, p=0.002). Mortality at 32-months and mortality in those surviving hospitalisation were similar at 78% vs. 73%, p=0.392 and 66% vs. 58%, p=0.355, for period 1 and 2 respectively. Conclusions Despite more advanced initial presentations, mortality rates have remained similar over the last 13 years. Serum creatinine at time of SBP diagnosis is an independent predictor of mortality.