Elevated effluent lactate independently predicts the adverse outcomes of peritoneal dialysis associated peritonitis

Peritonitis is the primary complication associated with peritoneal dialysis (PD). The acute inflammatory response is promoted by glycolysis, thereby enhancing lactate production. Lactate level has been identified as a prognostic factor of many acute inflammatory disease, however with no observation in peritoneal dialysis associated peritonitis (PDAP). Therefore, the need to monitor lactate levels of PDAP patients should be emphasized. Retrospective data on effluent and serum lactate levels and other clinical and laboratory characteristics for PDAP (2022-Nov to 2024-Jul) were analyzed. No-cure was defined as adverse outcomes like recurrence, relapse, catheter removal, hemodialysis transfer ≥ 30 days or death. We used logistic regressions and receiver operating characteristic curve (ROC) analysis to assess factors linked to outcomes and the lactate level predictive accuracy for PDAP adverse outcomes, respectively. The total number of PDAP episodes enrolled was 118, involving 100 PD patients. Regarding the clinical outcomes of the PDAP, 84 episodes were cured, while 34 episodes were no-cure. Catheter removal and transfer to hemodialysis were the leading adverse outcomes (n = 22, 64.7%), followed by relapse and recurrence. Compared with the cure group, no-cure group showed significantly lower serum albumin levels, higher effluent white cell count (WCC) on day 5, and higher percentage of gram-negative bacteria infections. The effluent lactate levels in no-cure group were statistically higher than those of cure group (8.50 [5.48, 13.1] versus 5.4 [3.18, 8.25] mmol/L, p < 0.001). Patients with higher effluent lactate levels (odds ratio [OR] = 1.419, p < 0.001) and gram-negative peritonitis (OR = 6.444, p = 0.009) had a higher risk of adverse outcomes. A moderate discriminative capacity for adverse outcomes was observed in the effluent lactate levels through ROC analyses (area under curve [AUC] = 0.752, p < 0.001), and with a threshold values of 10.2 mmol/L yielding the highest Youden's index. Elevated levels of lactate in the effluent may independently indicate adverse outcomes in PDAP.