Plasma and dialysate NtproBNP levels and and their clinical significance

INTRODUCTIONBrain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide(NTproBNP) are sub-fragments of the same molecule, and secreted in equimolarconcentration. Both molecules can be used as tools for diagnosis of the heart diseasesand risk stratification of the patients.OBJECTİVESPrimary objective of the study is to search a relation between plasma anddialysate NTproBNP concentrations. Secondary aims of the study are to search relationsof both plasma and dialysate NTproBNPs to some of the clinical and laboratory data ofthe patients.METHODSNTproBNP analysis were performed on simultaneously obtained plasma anddialysate samples of 44 peritoneal dialysis (PD) patients (19 males and 25 females)followed at Turgut Ozal Medical Centre Adult Nephrology clinic. All other clinical andlaboratory data were obtained from patients medical records. Data were analyzed byStandard statistical methods.RESULTSWe were able to detect NTproBNP from each sample. Medians were 3327 forplasma NTproBNP, 510 for dialysate NTproBNP, and mean plasma/dialysate (P/D)NTproBNP ratio was 5.5±0.5. P/D ratios in a subject were not constant over the time.Log10plasma NTproBNP and Log10dialysateNTproBNP were highly correlated (r =- 30 -0,928, p=0001, R2 = 0,861). Ratio of the patients with plasma NTproBNP concentrationbelow 300 pg/ml was just 6,8 %, and ratio of the patients with the concentration greaterthan 2000 pg/ml was 64%. Median plasma and dialysate NTproBNP concentration ofthe patients according to transport status of the peritoneal membrane were as follows:High (H)>high average (HA)>low average (LA) and the difference between H and LAgroups was statistically significant. Log10plasmaNTproBNPandLog10dialysateNTproBNP had similar correlation coefficient with mean arterialpressure, serum sodium and albumin levels.CONCLUSİONDialysate NTproBNP has potential t to provide almost all benefits provided byits plasma counterpart. Patients with higher membrane transport characteristics havehigher plasma and dialysate NTproBNP levels; this finding may be useful for riskstratification in the sub-groups of the peritoneal dialysis patients.