The following is the summary of “Influence of dietary protein on serum phosphorous levels in peritoneal dialysis patients with different initial transport function” published in the November 2022 issue of Renal failure by Wang, et al. 

In this cross-sectional investigation, the influence of dietary protein intake (DPI) on blood phosphate levels in peritoneal dialysis (PD) patients were explored, and the DPI cutoff that is necessary to prevent hyperphosphatemia was found. Fast peritoneal transporters had a dialysate/plasma [D/P] creatinine clearance of  ≥0.65 or higher after four hours, while slow peritoneal transporters had a D/P creatinine clearance of lower than 0.65 or below. 

There were 504 patients diagnosed with PD. The levels of phosphorus in the serum and the number of solutes cleared from the peritoneal fluid were compared across the groups with varying DPI. The fast peritoneal transporters (n=233) had a higher peritoneal phosphorus clearance, were older, had lower blood albumin levels, and had lower phosphorus levels (all P<0.001). Patients with a DPI greater than 1.0 g/kg/d had serum phosphorus levels that were statistically substantially higher than those of the slow transporters (n=271) (P<0.001). 

Only slow transporters saw increased hyperphosphatemia risk when high DPI levels were present (not in high transporters). In those patients, a DPI  ≥1.026 g was associated with an elevated risk of hyperphosphatemia (area under the curve: 0.66, P=0.001). Patients with Parkinson’s disease who have a slower peritoneal transport function are more likely to develop hyperphosphatemia if they have a high DPI.