Rifaximin alone vs combination with norfloxacin for secondary prophylaxis of spontaneous bacterial peritonitis with hepatic encephalopathy: randomized controlled trial

In liver cirrhosis, events of spontaneous bacterial peritonitis (SBP) and hepatic encephalopathy (HE) portend a poor prognosis. Gut dysbiosis remains a common pathogenetic mechanism for both SBP and HE. Recent data suggests the role of rifaximin in gut modulation and improving intestinal dysbiosis. Due to emergence of multidrug-resistant organisms, gut-selective antibiotics with minimal systemic effects are warranted for secondary prophylaxis in patients of cirrhosis. We compared rifaximin alone vs combination with norfloxacin for secondary prophylaxis of patients of cirrhosis presenting with SBP and HE. This was a prospective, open-label, RCT which included all patients of cirrhosis with SBP and HE on admission. On discharge, in addition to standard medical treatment, patients were randomized to rifaximin 400 mg three times a day (group I) and rifaximin 400 mg three times a day with norfloxacin 400 mg once a day (group II) as a secondary prophylaxis of SBP. Primary outcomes were recurrent episodes of SBP and HE at 6 months and 28-day, 90-day, and 6-month mortalities. Secondary outcomes included number of rehospitalizations, episodes of upper gastrointestinal bleed, new acute kidney injury episodes, and change in Child–Turcotte–Pugh (CTP) and model for end-stage liver disease (MELD) scores over next 6 months. After screening 87 patients of cirrhosis with SBP and HE, 12 patients had in-hospital mortality and another 25 were excluded, one patient was lost to follow-up, and, finally, 49 patients were randomized into group I (n = 24) and group II (n = 25). The HE was grade 2 (18 vs 16) and grade 3 (6 vs 9) in groups I and II respectively. Primary outcomes as recurrent SBP (3 vs 2; P = 0.67); recurrent HE at 6 months (5 vs 2; P = 0.24); and 28-day (2 vs 2; P = 1.0) and 90-day mortality (4 vs 3; P = 0.72) and 6-month mortality (6 vs 8, P = 0.52) were comparable between two groups respectively. Secondary outcomes as number of rehospitalizations (3 vs 8, P = 0.07), new episodes of UGI bleed (2 vs 3, P = 0.1), new AKI episodes (4 vs 1, P = 0.06), ∆CTP (− 4 vs − 4), and ∆MELD (− 9 vs − 8) over the next 6 months were not significantly different between two groups respectively. Rifaximin was effective in secondary prevention of both SBP and HE in patients of cirrhosis. The randomized controlled trial was registered in CTRI/2021/09/036321 dated September 7, 2021.