The timing of the first episode of peritonitis in peritoneal dialysis (PD) might have some special characteristics and may depend on many factors such as a patient's attitudes, age, comorbidity, or training capacity. It may also have a significant impact on further peritonitis episodes and technique failure. We retrospectively analyzed data for 168 PD patients who were undergoing continuous ambulatory PD by a twin-bag system, automated PD, or in-center intermittent PD over 12 years. There were 121 cases of peritonitis recorded in 60 patients, with an overall peritonitis rate of 1 episode per 45.75 patient-months. The mean time to the first episode of peritonitis after commencement of PD was 26.4 +/- 22 months (range: 1-110 months). In 20 patients, a first peritonitis episode presented rather early--during the first 12 months on PD (group A)--and in 27 patients, a first episode presented rather late-after at least 24 months on PD (group B). Group A had lower technique survival (30.4 +/- 26.5 months), were more prone to further episodes of peritonitis during follow-up, and had a total peritonitis rate of 1 episode per 14.85 patient-months. In group B, technique survival was longer (69.3 +/- 33.8 months), and the total peritonitis rate was 1 episode per 45.68 patient-months. We observed no differences between the two groups in comorbidity, age, or PD modality. These results indicate that patients with early-onset peritonitis are prone to making mistakes during connection, resulting usually in infection with gram-positive pathogens. These patients may present repeated peritonitis episodes and experience decreased technique survival.