Miguel Pérez Fontán

Peritonitis remains a leading complication of peritoneal dialysis (PD). It contributes to technique failure and hospitalization, and sometimes is associated with death of the patient. Severe and prolonged peritonitis can lead to peritoneal membrane failure. Therefore, the PD community continues to focus attention on prevention and treatment of PD-related infections.

Peritonitis is a well-known cause of mortality in peritoneal dialysis (PD) patients. We carried out a retrospective study to disclose the clinical spectrum and risk profile of peritonitis-related mortality. We analyzed 693 episodes of infectious peritonitis suffered by 565 patients (follow-up 1149 patient-years). Death was the final outcome in 41 cases (5.9% of episodes), peritonitis being directly implicated in 15.2% of the global mortality and 68.5% of the infectious mortality observed. In 41.5% of patients with peritonitis-related mortality, the immediate cause of death was a cardiovascular event. Highest mortality rates corresponded to fungal (27.5%), enteric (19.3%), and Staphylococcus aureus (15.2%) peritonitis. Multivariate analysis disclosed thatthe baseline risk of peritonitis-related mortality was significantly higher in female [relative risk (RR) 2.13, 95% confidence interval (CI) 1.24-4.09, p = 0.02], older (RR 1.10/year, CI 1.06-1.14, p < 0.0005), and malnourished patients (RR 2.51, CI 1.21-5.23, p = 0.01) with high serum C-reactive protein (s-CRP) levels (RR 4.04, CI 1.45-11.32, p = 0.008) and a low glomerular filtration rate (RR 0.75 per mL/minute, CI 0.64 -0.87, p < 0.0005). Analysis of risk after a single episode of peritonitis and/or subanalysis restricted to peritonitis caused by more aggressive micro-organisms disclosed that overall comorbidity [odds ratio (OR) 1.21, CI 1.05-1.71, p = 0.005], depression (OR 2.35, CI 1.14-4.84, p = 0.02), and time on PD at the time of the event (OR 1.02/month, CI 1.00-1.03, p = 0.02) were other predictors of mortality. In summary, the etiologic agent is a definite marker of peritonitis-related mortality but gender, age, residual renal function, inflammation (s-CRP), malnutrition, and depression are other significant correlates of this outcome. Most of these risk factors are common to cardiovascular and peritonitis-related mortality, which may explain the high incidence of cardiovascular event as the immediate cause of death in patients with peritonitis-related mortality.