Objective: Changes in bacteriology of spontaneous bacterial peritonitis (SBP) has been documented. Reappraisal of primary SBP prophylaxis showed an increased rate of resistance in patients on primary prophylaxis with resultant discontinuation of this prophylaxis throughout the VA. We aimed to re-evaluate the risk-benefit ratio of secondary SBP prophylaxis (SecSBPPr). Design: Using validated ICD 9/10 codes, we utilized the VA Corporate Data Warehouse and the Non-VA National TriNetX database to identify patients in two different large US systems who survived their first SBP diagnosis (with confirmatory chart review from two VA centers) between 2009-2019. We evaluated the prevalence of SecSBPPr and compared outcomes between those started on SecSBPPr versus not. Results: We identified 4673 Veterans who survived their index SBP episode; 54.3% of whom were prescribed SecSBPPr. Multivariable analysis showed higher SBP recurrence risk in those on vs. off SecSBPPr (HR-1.63, p<0.001). This was accompanied by higher fluroquinolone-resistance risk in patients on SecSBPPr (OR=4.32, p=0.03). In TriNetX we identified 6708 patients who survived their index SBP episode; 48.6% were on SecSBPPr. Multivariable analysis similarly showed SecSBPPr increased the risk of SBP recurrence (HR-1.68, p<0.001). Both groups showed higher SBP recurrence trends over time in SecSBPPr patients. Conclusion: In two national data sets of >11,000 patients with SBP we found that SecSBPPr was prescribed in roughly half of patients. When initiated, SecSBPPr, compared to no prophylaxis after SBP, increased the risk of SBP recurrence in multivariable analysis by 63-68%, and this trend worsened over time. SecSBPPr should be reconsidered in cirrhosis.

The authors have declared no competing interest.

Partly supported by VA Merit Review I01CX001076 and I01CX002472 to JSB and Richmond Institute for Veterans Research and VCU Wright Center CTSA UM1TR004360.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

IRB of Virginia Commonwealth University waived ethical approval for this work IRB of Richmond Veterans Affairs Medical Center gave ethical approval for this work

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