Clinical significance and diagnostic value of serum progastrin-releasing peptide in patients with chronic kidney diseases

Objective To investigate the clinical significance and diagnostic value of serum progastrin-releasing peptide(proGRP) in patients with chronic kidney diseases (CKD).

Methods The clinical data of 259 hospitalized patients with CKD in the department of nephrology were retrospectively analyzed. A total of 167 patients without dialysis were divided into five groups according to estimated glomerular filtration rate (eGFR) staging (CKD stages 1 to 5), 92 patients receiving dialysis treatment were divided into two groups (hemodialysis group and peritoneal dialysis group) according to the way of dialysis, and another 31 healthy subjects were included in control group. The levels of serum proGRP and markers of kidney disease were compared between the control group and CKD groups with different stages, and the correlations of serum proGRP with serum creatinine, eGFR, urea nitrogen, uric acid, cystatin C, blood β2 microglobulin, serum albumin and hemoglobin were analyzed. The optimal cut-off value of serum proGRP for predicting occurrence of eGFR < 60 mL/min (progression to CKD3) was calculated by receiver operating characteristic (ROC) curve.

Results The serum proGRP levels of patients in the CKD3 stage group, the CKD4 stage group and the CKD5 stage group were higher than those in the control group(P < 0.05), and the serum proGRP levels gradually increased with the increase of CKD stage. Serum proGRP was significantly correlated with serum creatinine (r=0.910, P < 0.01), eGFR (r=-0.917, P < 0.01), urea nitrogen (r=0.881, P < 0.01), serum uric acid (r=0.641, P < 0.01), cystatin C (r=0.919, P < 0.01), serum β2 microglobulin (r=0.855, P < 0.01), serum albumin (r=-0.297, P < 0.01) and hemoglobin (r=-0.623, P < 0.01). ROC curve analysis showed that when the optimal cut-off value of serum proGRP was 67.20 pg/mL, the sensitivity and specificity of predicting CKD3 stage was 84.1% and 100.0%. There was no significant difference in serum proGRP level between the hemodialysis group and the peritoneal dialysis group (P>0.05).

Conclusion Serum proGRP levels in patients with CKD are higher than those in healthy subjects, and are increased with the increase of CKD stages, thus serum proGRP level can be used to evaluate the severity of CKD. Serum proGRP is positively correlated with serum creatinine, urea nitrogen, uric acid, cystatin C and β₂ microglobulin, while is negatively correlated with eGFR, serum albumin and hemoglobin.