Autori: Grazia Maria Virzì, Sabrina Milan Manani, Anna Clementi, Silvia Castegnaro, Alessandra Brocca, Caterina Riello, Massimo de Cal, Anna Giuliani, Giovanni Giorgio Battaglia, Carlo Crepaldi, Claudio Ronco
Affiliazioni: Department of Nephrology, Dialysis and Transplant, St Bortolo Hospital and IRRIV- International Renal Resarch Institute, Vicenza, Italy
RBCs have a highly specialized and organized membrane structure which interacts with xenobiotic and endogenous substances. They undergo programmed cell death known as eryptosis. Recent reports have demonstrated enhanced percentage of PS-exposing RBCs, reflecting eryptosis, in PD patients compared to healthy subjects. In this study, we investigated the relationship between residual glomerular filtration rate (rGFR) and eryptosis in PD patients.
We enrolled 46 PD patients and we divided them in 2 groups according to the presence of residual diuresis. We considered 24 hours urine volume of 500 mL or less negligible in terms of residual renal function. All eryptosis measurements were made by flow cytometer.
23/46 patients had a residual diuresis: the median daily urine volume was 1000 ml (IQR 662.5-1450) and the median rGFR was 2.95 ml/minutes (IQR 1.95-4.6). On the contrary, 23 patients had a residual diuresis ≤ 500 ml. Eryptosis showed significantly lower levels in PD patients with residual diuresis (n=23) than in patients without (3.7%, 2.6-5.6 versus 5%, 3.1-16; p=0.03). Furthermore, a significant negative correlations between percentage of eryptosis and rGFR (Spearman’s rho=- 0.51, p=0.01) and diuresis volume (Spearman’s rho=- 0.43, p=0.05) were found.
On the basis of these results, we hypothesized that in PD patients, an increase in eryptosis levels may result from the progressive residual diuresis loss, probably due to a decreased uremic toxins clearance. These data confirm the important role of maintaining residual diuresis and rGFR in PD patients.