Aim. To evaluate the role of lactoferrin and lactoferricin in blood serum and urine in patients with an attack of renal colic against the background of urolithiasis and pyelonephritis.
Materials and methods. We examined 149 patients admitted to the urological department of the City Clinical Hospital No. 3 of Astrakhan, according to emergency indications, with an attack of renal colic. Along with standard clinical, laboratory and instrumental research methods (general blood count, biochemical blood test, urinalysis, kidney ultrasonography), the concentration of CRP and lactoferrin was measured in all patients in the blood and urine using a set of reagents for ELISA (Lactoferrin «Vector-Best» Novosibirsk city). The sensitivity of the test for CRP and LF was 3–5 µg/ml and 5 ng/ml, respectively. Studies of all collected material for lactoferricin were carried out deferred in the laboratory of the Astrakhan State Medical University. Based on the results of clinical and instrumental studies, patients admitted with an attack of renal colic were retrospectively divided into three groups: the first group included 38 patients with urolithiasis. The second group included 64 patients with obstructive pyelonephritis, and the third group included 47 patients hospitalized with characteristic signs of primary non-obstructive pyelonephritis. The groups were matched by sex and age. Blood and urine samples from 25 donors served as controls.
Results. When comparing a group of patients with urolithiasis with a group of patients with non-obstructive and obstructive pyelonephritis, highly significant differences (p<0.0001) were found in LF, LFC, CRP and the number of leukocytes in the blood and urine sediment. In urine, according to the results of ROC-analysis in couples with urolithiasis without pyelonephritis in comparison with obstructive pyelonephritis, the most significant differences were established for all four parameters studied: for LF (AUC=0.823), for LFC (AUC=0.832), for CRP (AUC=0.829 ) and the number of leukocytes in the urine sediment (AUC=0.780).
Discussion. In blood and urine in patients with urolithiasis and pyelonephritis, the effects of the bactericidal peptide LPC were compared with the levels in biological f luids of CRP, LF, and the number of leukocytes. The greatest diagnostic value of all four studied indicators was found in urine, and not in serum. ROC-analysis confirmed a more significant effect of the studied parameters on pyelonephritis than on urolithiasis. The level of lactoferrin and CRP in patients at admission correlates with the number of leukocytes in the blood and urine sediment and with the degree of inflammation in the body. And the level of LFC peptide in the urine reflects the degree of infection of the urinary tract.
Conclusions. A comparative study of tests for Lf and LFC in blood serum and urine in patients admitted to a urological hospital with an attack of renal colic was carried out. Determining the concentration of lactoferricin in the urine is an informative indicator. Thus, lactoferrin and its hydrolysis product lactoferricin reflect different aspects of the infectious and inflammatory process in pyelonephritis.

Keywords: determination in blood and urine, lactoferricin, diagnostic value, CRP, lactoferrin, pyelonephritis, urolithiasis