Clinical Significance and Outcome of Nosocomial Acquisition of Spontaneous Bacterial Peritonitis in Patients with Liver Cirrhosis

Background. There have been few reports on the causes and treatment outcomes for nosocomial spontaneous bacterial peritonitis (SBP) in patients with liver cirrhosis. Methods. We performed a retrospective cohort study to compare the microbiological and clinical characteristics in nosocomial versus community-acquired SBP. All patients with SBP, for whom culture was proven to be positive for SBP at Samsung Medical Center (Seoul, Republic of Korea) from 1 January 2000 through 31 June 2007, were included. Medical records and laboratory data were reviewed. Nosocomial SBP was defined as SBP diagnosed after 72 h of hospitalization. Results. A total of 236 patients with SBP were enrolled (mean age +/- SD age, 56.6 +/- 10.7 years); 166 patients were women, and 70 were men. Nosocomial and community-acquired SBP occurred in 126 and 110 patients, respectively. Escherichia coli accounted for 102 (43.2%) of 236 isolates, Klebsiella species accounted for 33 isolates (14.0%), and Streptococcus species accounted for 23 isolates (9.8%). The overall 30-day mortality rate for nosocomial SBP was higher than that for community-acquired SBP (58.7% vs. 37.3%; P = .001). Nosocomial isolates of gram-negative organisms were significantly more resistant to third-generation cephalosporins (41% vs. 10.0%; P <.001) and quinolones (50.0% vs. 30.9%; P = .003), compared with community-acquired isolates. Multivariate analysis revealed that nosocomial infection, concomitant hepatocellular carcinoma, presentation with acute renal failure or shock, and resistance to third-generation cephalosporins were significant risk factors for 30-day mortality associated with SBP. Conclusions. Nosocomial SBP has a poorer outcome than community-acquired SBP. The resistance to third-generation cephalosporins for gram-negative organisms, which are more common in nosocomial cases of SBP than in community-acquired cases of SBP, adversely affects the outcome of SBP in patients with liver cirrhosis.