The study of procalcitonin (PCT) in blood serum is widely used to diagnose bacterial infection and evaluate the effectiveness of antibacterial therapy, including in patients with renal insufficiency.
THE AIM
To study the concentration of PCT in blood serum in patients with end-stage chronic kidney disease (CKD) in comparison with healthy individuals.
MATERIALS AND METHODS
The concentration of PCT was determined in the blood serum of 89 patients, including men (n=42) and women (n=47). The patients were divided into three groups: the main group (group 1, n=31), which included patients with end-stage CKD. The comparison group (group 2) consisted of patients (n=21) with local inflammatory surgical diseases with normal results of general urinalysis and serum creatinine concentration. The control group (group 3) consisted of 37 healthy people who underwent periodic preventive examination. The concentration of PCT (ng/ml) in blood serum was determined by solid—phase enzyme immunoassay (ELISA) using a commercial test system «Procalcitonin — ELISA — BEST» (A 9004) (Vector — Best, Russia). The concentration of CRP (mcg/ml) and creatinine was determined using an ARCHITECT c8000 biochemical analyzer (Abbott, USA) using original reagents.
RESULTS AND DISCUSSION
The highest level of PCT — 2.57±2.40 ng/ml was found in patients of the main group, while the difference between the medians of its content in the serum of the main and control groups was 7.67 times (p<0.0001). An increase in the content of PCT in the blood correlated with the degree of decrease in glomerular filtration rate (GFR): Spearman correlation coefficient R= –0.676997, p<0.00001. The hemodialysis procedure was accompanied by a statistically significant decrease in the level of PCT (p=0.000009).
CONCLUSIONS
The obtained results indicate that the kidneys play an important role in the metabolism of PCT and, in particular, the elimination of this protein from the blood serum. When interpreting the results of the study of PCT in the blood, a nonspecific increase in its content with a decrease in CFR should be taken into account. In patients with low CFR, higher discriminatory levels should be used to stratify systemic inflammatory reaction.
