Viridans group streptococci causing spontaneous bacterial peritonitis and bacteremia in patients with end-stage liver disease

Proton Pump Inhibitor Initiation and Withdrawal affects Gut Microbiota and Readmission Risk in Cirrhosis

OBJECTIVES

Cirrhosis is associated with gut microbial dysbiosis, high readmissions and proton pump inhibitor (PPI) overuse, which could be inter-linked. Our aim was to determine the effect of PPI use, initiation and withdrawl on gut microbiota and readmissions in cirrhosis.

METHODS

Four cohorts were enrolled. Readmissions study: Cirrhotic inpatients were followed throughout the hospitalization and 30/90-days post-discharge. PPI initiation, withdrawal/continuation patterns were analyzed between those with/without readmissions. Cross-sectional microbiota study: Cirrhotic outpatients and controls underwent stool microbiota analysis. Beneficial autochthonous and oral-origin taxa analysis vis-à-vis PPI use was performed. Longitudinal studies: Two cohorts of decompensated cirrhotic outpatients were enrolled. Patients on chronic unindicated PPI use were withdrawn for 14 days. Patients not on PPI were started on omeprazole for 14 days. Microbial analysis for oral-origin taxa was performed pre/post-intervention.

RESULTS

Readmissions study: 343 inpatients (151 on admission PPI) were enrolled. 21 were withdrawn and 45 were initiated on PPI resulting in a PPI use increase of 21%. PPIs were associated with higher 30 (p = 0.002) and 90-day readmissions (p = 0.008) independent of comorbidities, medications, MELD and age. Cross-sectional microbiota: 137 cirrhotics (59 on PPI) and 45 controls (17 on PPI) were included. PPI users regardless of cirrhosis had higher oral-origin microbiota while cirrhotics on PPI had lower autochthonous taxa compared to the rest. Longitudinal studies: Fifteen decompensated cirrhotics tolerated omeprazole initiation with an increase in oral-origin microbial taxa compared to baseline. PPIs were withdrawn from an additional 15 outpatients, which resulted in a significant reduction of oral-origin taxa compared to baseline.

CONCLUSIONS

PPIs modulate readmission risk and microbiota composition in cirrhosis, which responds to withdrawal. The systematic withdrawal and judicious use of PPIs is needed from a clinical and microbiological perspective in decompensated cirrhosis.

Polymorphonuclear counts in ascitic fluid and microorganisms producing spontaneous bacterial peritonitis: an under-recognized relationship

BACKGROUND AND AIMS. In cirrhotic patients with spontaneous bacterial peritonitis (SBP) higher polymorphonuclear (PMN) count in ascitic fluid have been reported in infections caused by Gram-negative bacilli (GNB) as opposed to Gram-positive cocci (GPC). However, the influence of other associated factors on the PMN count, such as the specific microorganism causing the episode of SBP, has not been well established. METHODS. Retrospective observational study of 194 episodes of positive ascitic and/or blood culture SBP in 159 patients with liver cirrhosis (2001-2009). Parameters associated with PMN count in ascitic fluid at diagnosis were evaluated. RESULTS. The multivariate analysis (model 1) showed that a virulent etiology of the infection [coefficient 3.941 (95% confidence interval (95 CI): 0.421-7.461)] and the model for end-stage liver disease (MELD) score [coefficient 0.196 (95 CI: 0.007-0.384)] were positively associated with the PMN count in ascites, while a nosocomial acquisition was inversely associated [coefficient -3.546 (95 CI: -6.855 - -0.238)]. A nonsignificant trend toward higher PMN count was found in GNB versus GPC, but there were differences between groups of microorganisms: pyogenic streptococci [median (p25-p75): 3211 (1615-8004)], Enterobacteriaceae [2958 (917-7690)], Vibrionaceae [9215 (375-17280)], nonfermenting GNB [1384 (565-3865)], viridans group streptococci [1044 (503-2354)] and enterococci [1050 (476-4655)](p = 0.005). No clear cut-offs of ascitic PMN count predicting a particular etiology could be calculated out of these data. CONCLUSIONS. In cirrhotic patients with SBP, the causing microorganism, the place of acquisition of the infection and the host liver condition were the main factors determining PMN count in ascitic fluid. Third-generation cephalosporin resistance was associated with low PMN count probably because this group included bacteria with inherent low virulence.

Identification of bacterial DNA in neutrocytic and non-neutrocytic cirrhotic ascites by means of a multiplex polymerase chain reaction

BACKGROUND

Even though bacterial cultures of ascitic fluid are negative in up to 65% of the cases of spontaneous bacterial peritonitis (SBP); bacterial DNA (bactDNA) has been frequently detected in episodes of SBP as well as in culture-negative non-neutrocytic ascites.

AIMS

To evaluate multiplex polymerase chain reaction (PCR) for pathogen identification in SBP and to determine the prevalence of ascitic bactDNA and its prognostic relevance in hospitalized patients with liver cirrhosis.

METHODS

Ascitic fluid from 68 consecutive patients who underwent diagnostic paracentesis was analysed for polymorphonuclear leucocyte (PMN) count, bacterial culture and bactDNA. BactDNA was identified by gel analysis after multiplex PCR of selectively enriched prokaryotic nucleic acids. Correlations of bactDNA status with PMN count, bacterial culture result and 3-month mortality were determined for neutrocytic and for non-neutrocytic ascites.

RESULTS

11/68 patients presented with an elevated ascitic PMN count. BactDNA was detected in 5/5 culture-positive neutrocytic samples, in 1/6 culture-negative neutrocytic samples and in 8/56 culture-negative non-neutrocytic samples. Three-month mortality did not differ with respect to ascitic bactDNA status (7/14 vs. 14/47, P=0.162). 3-month mortality was increased in the presence of ascitic bactDNA for patients older than 65 years (4/5 vs. 4/14, P=0.046) and for patients with a model for end-stage liver disease score >15 (7/10 vs. 9/30, P=0.025).

CONCLUSIONS

Identification of ascitic bactDNA is an appropriate alternative to bacterial ascite culture for pathogen identification in patients at risk for SBP. Its prognostic relevance as a proposed marker of bacterial translocation for certain risk groups has to be further evaluated.