Simposio Fosforo e MBD in PD: vecchi e nuovi protagonisti Rimozione del fosforo e dialisi peritoneale Roberto Russo

Hyperphosphatemia is a predictor of overall and CV mortality Noordzij M et al NDT 21: 2513–2520,2006

Serum Phosphorus and Mortality in Dialysis Patients Ansell D et al NDT 22: 667, 2007

Serum Phosphorus and Mortality in PD Patients Data on 7034 PD patients who attended Da Vita dialysis clinics for at least 3 months Mehrotra et al Perit Dial Int 27: Suppl 3, S12, 2007

Percentage achievement of the K/DOQI guideline for bone metabolism 40% Calcium Phosph CaxP iPTH Noordzij M et al NDT 21: 2513–2520,2006

Management of hyperphosphatemia in PD patients

• • Dietary phosphate restriction Removal of phosphate by dialysis and residual renal function • Administration of phosphate binder

Total body phosphate

bone and teeth intracellular fluid 1% 14% extracellular fluid

700 g

85%

Phosphate balance in dialyzed patients Diet Intestinal absorption (50-70%) Removal (HD) Removal (PD) Difference 1000 mg/d 600 mg/d 7000 mg/week 4200 mg/week 800 mg/session 300-400 mg/d 2400 mg/ week 2400 mg/ week + 1800 mg/ week Ketteler M, Gross ML, Ritz E. Kidney Int 2005;67:s120-7

Sedlacek M et al Am J Kidney Diseases 2000; 36: 1020-1024

Bammens B et al Am J Kidney Dis 2005; 46: pp 512-519

Superior dialytic clearance of |[beta] |2-microglobulin and p-cresol by high-flux hemodialysis as compared to peritoneal dialysis

• •

Phosphate clearance

55 L/1.73 m 2 in APD 34 patients 66 L/1.73 m 2 in CAPD 16 patients

Enevepoel P et al Kidney Int 2006; 70:794-9

Is it possible to control hyperphosphataemia with diet?

Serum P 5.5 mg/dl PCl 57L/week

5,5 mg/dl x 57 L / sett = 3135 mg of P - 3135/7 = 447 mg 60-64 g proteine x 14-15 mg (contenuto di P x g proteine) = 960 mg/2 = 480 mg Rufino M et al Nephrol Dial Transplant 1998; 13(Suppl 3): 65–67

Urinary phosphate excretion

• • CAPD patients urinary excretion (48.8+21.4) represent about 40% of the total Pi removed Urinary Pi excretion was linearly related to GFR values

Messa P et al Nephrol Dial Transplant 1998; 13 (Suppl 6): 43–48

Residual Renal Function and Phosphate Levels

• • Only 29% of patients with preserved RRF had a serum phosphate concentration > 5.6 mg/dl as compared with 44% of the anuric patients Residual GFR was an important predictor of serum phosphate levels in a cross sectional study of over 250 prevalent PD patients

Wang AYM et al Amer J Kidney Dis 2004; 43: 712-720

Urinary phosphate excretion

Bammens B et al Amer J Kidney Dis 2005; 46: 512-519

Sopravvivenza dei pazienti in dialisi peritoneale

With RRF No RRF Follow-up months Wang AYM, Nephrol Dial Transplant 2005

Phosphate control with nocturnal HD CHD NHD Mucsi I et al Kidney Int 1998

Phosphate control with nocturnal HD Lindsay RM et al Amer J Kidney Dise 2003; 42: (Suppl 1) S24-S29

D/P Ratio of Solutes in PD

1,0 0,9 0,7 D/P 0,4 UREA CREATININE PHOSPHATE

2 4

Tempo di stazionamento (ore)

8

Transperitoneal phosphate transport

• • • Convention Diffusion down an electrochemical gradient Lymphatic convective absorption is not a factor

Graff J et al Clin Physiol 1996; 16:291-300

Phosphate removal on PD

mg 0 50 100 150 200 250 300 350 Daily transfer 1.5% 4.25% 66 mg P < 0.001

111 mg

Delmez JA et al Kidney Int 1982; 21: 862—867

Predictors of phosphate removal

Messa P et al Nephrol Dial Transplant 1998; 13 (Suppl 6): 43–48

Association between 24-hour UF and percent of phosphate removed by UF

Granja CA et al Contrib Nephrol 2009; 163:198-205

Phosphate Balance in Peritoneal Dialysis: Role of Ultrafiltration

Granja CA et al Contrib Nephrol 2009; 163:198-205

Phosphate clearance according to peritoneal membrane transport characteristic Sedlacek M et al Am J Kidney Diseases 2000; 36: 1020-1024

Phosphate clearance according to peritoneal membrane transport characteristic Badve SV et al Clin J Am Soc Nephrol 2008; 3: 1711–1717

Relation between the D/P ratios and clearance of phosphorus and creatinine Sedlacek M et al Am J Kidney Diseases 2000; 36: 1020-1024

Determinants of peritoneal phosphate clearance, by linear regression Badve SV Clin J Am Soc Nephrol 2008; 3: 1711–1717

Phosphate clearance according to peritoneal membrane transport characteristic

60 50 40 30 20 10 0 49,5 49,7 CAPD APD 42,4 36,4 35,6 28,9 H HA LA & L

Badve SV Clin J Am Soc Nephrol 2008; 3: 1711–1717

Phosphate clearance according to peritoneal membrane transport characteristic IPD 15x2 totale 30 L - TPD (50%) 29x1 totale 30 L

Piraino B et al Perit Dial Int 1994; 14:145-148

Peritoneal Phosphate clearances according to PD modality

30 20 10 0 60 50 40 Evenepoel Sedlacek Gallar * *

CCPD2

CAPD CCPD

The impact of various NIPD cycling regimens on phosphorus removal in chronic PD patients

5 2 1 4 3

3,96 + 1,36 4,71 + 1,81 4,51 + 1,61 14 L

7 cycles of 2 L

24 L

12 cycles of 2 L

24 L

24 cycles of 1 L (Tidal 50%)

Juergensens P et al Int J Artif Organs 2005;28:1219-23

A comparison of clearances on tidal peritoneal dialysis and intermittent peritoneal dialysis IPD 15x2 totale 30 L - TPD (50%) 29x1 totale 30 L

Piraino B et al Perit Dial Int 1994; 14:145-148

Adequacy of automated peritoneal dialysis with and without manual daytime exchange: a randomized controlled trial

P = 0.68

8,0 7,0 6,0 5,0 4,0 3,0 2,0 1,0 0,0 7,6 + 2,0 7,7 + 1,7

CCPD CCPD 2

Demetriou D et al Kidney Int 2006; 70:1649-55

Conclusions 1

• • • • •

Total phosphate clearance depends on both RRF and peritoneal clearance and may fall substantially as RRF declines Phosphate clearances are limited with PD therapy Phosphate clearance on NIPD is inferior to that on CAPD because of time dependent removal of phosphate High flow CCPD may produce a marginal increase in peritoneal phosphate clearance CCPD and CCPD2 do not appear to have major differences

Conclusions 2

•

There is a real concern that with reduction in K/DOQI guidelines to KT/V 1.7, phosphate removal with PD will be further compromised

•

To prevent hyperphosphatemia most patients undergoing PD

phosphate binder

require an

exogenus