Diagnostic and prognostic role of peritoneal CA 125 in peritoneal dialysis patients presenting with acute peritonitis

The relationship between changes in peritoneal permeability with CA-125 and HIF-1α

BACKGROUND

Peritoneal fibrosis (PF) is a major, persistent complication of prolonged peritoneal dialysis that eventually leads to peritoneal ultrafiltration failure and termination of peritoneal dialysis. Prolonged exposure to high glucose concentrations, degradation products, uremic toxins, and episodes of peritonitis can cause some changes in the peritoneal membrane, resulting in intraperitoneal inflammation and PF, leading to failure of ultrafiltration and dialysis. CA-125 can be used as a biomarker of peritoneal mesothelial cell count in the peritoneal dialysate and for monitoring cell count in PD patients. Hypoxia-inducible factor 1-alpha (HIF-1α) has been reported to cause PF, but has not been reported to be associated with changes in peritoneal structure. We hypothesized that peritoneal adequacy can be followed using HIF-1α and CA-125 values. In the present study, therefore, we investigated the relationship between HIF-1α and CA-125 levels and parietal membrane permeability changes in PD patients.

METHODS

Forty-five patients were included in the study. Peritoneal permeability was constant in 20 of these, while peritoneal permeability increased in 11 and decreased in 14. The HIF-1α value from the blood samples of the patients and the CA-125 measurement from the peritoneal fluids were measured. The relationship between peritoneal variability and CA-125 and HIF levels after follow-up was investigated.

RESULTS

We compared serum HIF-1α and peritoneal fluid CA-125 levels in the three groups receiving peritoneal dialysis treatment. HIF-1α levels increased with peritoneal permeability changes, while CA-125 levels decreased. In patients with high to low permeability changes, HIF-1α levels were higher compared to those with stable or low to high changes, which was statistically significant. Conversely, CA-125 levels significantly decreased in patients whose peritoneal permeability changed from high to low, compared to the other two groups.

CONCLUSION

Changes in peritoneal structure can be followed with biomarkers. It has been shown that CA-125 and HIF-1α levels can guide the changes in the peritoneal membrane. This can be useful in the monitoring of peritoneal dialysis.

CA-125 and CCL2 may indicate inflammation in peritoneal dialysis patients

Introduction:

Progressive structural changes in the peritoneal membrane occur over the course of treatment in peritoneal dialysis (PD), resulting in an increase in cytokines such as CCL2 and structural changes in peritoneal membrane triggering an increase in CA-125 in dialysate, which reflects a probable local inflammatory process, with possible loss of mesothelial cells. Thus, the current study aimed to evaluate the association between plasma and CCL2 and CA-125 dialysate levels in patients undergoing PD.

Methods:

Cross-sectional study was conducted with 41 patients undergoing PD. The assessments of CA-125 and CCL2 levels were performed using a capture ELISA. Correlations were estimated using Spearman's correlation and the investigation of the association between the explanatory variables (CCL2) and response variable (CA-125) was done for crude ratio of arithmetic means and adjusted utilizing generalized linear models.

Results:

A moderate positive correlation was observed between the levels of CA-125 and CCL2 in the dialysate (rho = 0.696). A statistically significant association was found between the levels in the CCL2 and CA-125 dialysate (RoM=1.31; CI = 1.20-1.43), which remained after adjustment for age (RoM = 1.31; CI=1.19-1.44) and for time in months of PD (RoM=1.34, CI=1.22-1.48).

Conclusion:

The association of CA-125 levels with CCL2 in the dialysate may indicate that the local inflammatory process leads to temporary or definitive changes in peritoneal membrane. A better understanding of this pathogenesis could contribute to the discovery of new inflammatory biomarkers.

High Intraperitoneal Interleukin-6 Levels Predict Peritonitis in Peritoneal Dialysis Patients: A Prospective Cohort Study

BACKGROUND

To evaluate the predictive value of dialysate interleukin-6 (IL-6) representing local subclinical intraperitoneal inflammation for the development of peritonitis in continuous ambulatory peritoneal dialysis (CAPD) patients.

METHODS

Stable prevalent CAPD patients were enrolled in this prospective study. IL-6 concentration in the overnight effluent was determined and expressed as the IL-6 appearance rate (IL-6AR). Patients were divided into 2 groups according to the median of IL-6AR and prospectively followed up until the first episode of peritonitis, cessation of PD, or the end of the study (December 30, 2017). The utility of IL-6AR in predicting peritonitis-free survival was analyzed using the Kaplan-Meier and Cox proportional hazards models.

RESULTS

A total of 149 patients were enrolled, including 72 males (48%) with mean age 52.0 ± 13.6 years and median PD duration 26 (5.9-45.5) months. During follow-up, 7,923 patient months were observed and 154 episodes of peritonitis occurred in 82 patients. Previous peritonitis episodes were significantly associated with log dialysate IL-6AR levels (β = 0.187 [0.022-0.299], p = 0.023). Patients in the high IL-6AR group showed a significantly inferior peritonitis-free survival when compared with their counterparts in the low IL-6AR group (48.8 vs. 67.7 months, p = 0.026), as well as higher treatment failure percentage of peritonitis (20.3 vs. 9.3%, p = 0.049). A multivariate Cox regression showed that high dialysate IL-6AR (hazard ratio [HR] 1.247 [1.052-1.478]; p = 0.011) and high serum C-reactive protein (HR 1.072 [1.005-1.144]; p = 0.036) were independent risk factors for inferior peritonitis-free survival.

CONCLUSION

This prospective study suggested that the intraperitoneal inflammation marker, dialysate IL-6 level, might be a potential predictor of peritonitis development in patients undergoing PD.