Purpose of the study: Research of the clinical and diagnostic significance of determination of Lipocalin-2 associated with neutrophilic gelatinases (uNGAL) in the urine of children with urinary tract infection (UTI) and pyelonephritis. Materials and methods: We examined 30 children with acute pyelonephritis and UTI aged 1 to 16 years (average age 7.32 ± 4.52) including 26 girls and 4 boys. Verification of the diagnosis was conducted on the basis of clinical and laboratory data, medical history and instrumental examination of patients. All children were divided into 2 groups: 1st group—15 children with acute pyelonephritis, 2nd group—15 children with urinary tract infection. uNGAL was measured in the urine by enzyme-linked immunosorbent assay (EISA) (BioVendor Laboratoty Medicine). Results: It is found, that the urine level of NGAL depends on the damage degree of renal parenchyma. The correlation of medium strength was found between the excretion level of uNGAL during the acute period of pyelonephritis and the detection of renal scars according to the DMSA-nephroscintigraphy data. In the group of children with the acute pyelonephritis the direct correlation of medium strength was found between the excretion level of uNGAL/creatinine and leukocytosis value and also with the CRP blood level. Conclusion: The results allow us to recommend the determination of the excretion level of uNGAL/creatinine as an additional non-invasive marker for the early detection of renal parenchyma injury.
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