♦ Background: Peritonitis is a major cause of morbidity, mortality, and technique failure in peritoneal dialysis (PD) patients, especially when caused by enteric microorganisms (EM). We have implemented a treatment protocol specifically aimed at improving the outcome in EM peritonitis. The adapted protocol was applied in all PD patients 50 years and older presenting with peritonitis who were considered to be at risk of EM peritonitis and involves 3 interventions: 1) temporary discontinuation of PD without removing the catheter (peritoneal rest), 2) intravenous meropenem, and 3) meropenem intracatheter as lock (Mero-PerRest protocol). ♦ Methods: In this observational study, we compared the outcome of 203 peritonitis episodes in 71 patients treated with the Mero-PerRest protocol, with 217 episodes in 104 patients treated with a more traditional intraperitoneal gentamicin-rifampicin-based regimen. ♦ Results: In EM peritonitis episodes, the Mero-PerRest protocol resulted in a higher primary cure rate (90.0% vs 65.3%, adjusted odds ratio [OR] 4.54 [95% confidence interval (CI) 1.46 – 14.15]) and better technique survival (90.0% vs 69.4%, adjusted OR 3.41 [95% CI 1.07 – 10.87]). This effect was most distinct in patients with polymicrobial EM peritonitis (cure rate 87.5% vs 34.8%, p = 0.0003). Interestingly, primary cure rate (95.6% vs 84.7%, adjusted OR 3.92 [95% CI 1.37 – 11.19]) and technique survival (95.6% vs 85.6%, adjusted OR 3.60 [95% CI 1.25 – 10.32]) were also excellent in non-EM peritonitis episodes. Patient survival did not differ significantly. ♦ Conclusion: The poor outcome of peritonitis caused by EM in PD patients aged 50 years and older could be improved by applying a treatment protocol involving temporary discontinuation of PD without catheter removal and intravenous and intracatheter meropenem.