The role of increased intestinal permeability markers in developing urinary tract infection in children of the first three years of life

Urinary tract infection (UTI) is one of the urgent problems in pediatric nephrology and pediatrics. Despite numerous works devoted to the study of pathogenetic mechanisms and development of new diagnostic measures in patients with urinary tract infection, many questions on pathogenesis have not yet been clearly elucidated. Considering that non-specific symptoms prevailing in the disease clinical picture in children of the first three years of life, it is necessary to search for reliable, early, non-invasive methods for diagnosing urinary tract infections. Purpose of the study is to determine diagnostic and pathogenetic significance of proteins that bind fatty acids as well as zonulin in diagnosis of urinary tract infection in children of the first three years of life. Materials and methods. There were examined 120 children, aged from 29 days of life to 2 years 11 months and 29 days inclusive with urinary tract infection. Control group — 30 healthy children. All children were tested for serum level of proteins that bind fatty acids L-FABP and I-FABP, and the level of I-FABP, L-FABP and zonulin was measured in urine by enzyme-linked immunosorbent assay. Results. In the blood serum of children with urinary tract infection, the levels of L-FABP and I-FABP were significantly increased compared with those in children of the control group (L-FABP — 753.94±26.16 ng/ml vs. 148.7±19.6 ng/ml, I-FABP — 92.97±1.41 ng/ml vs. 18.03±3.03 ng/ml, respectively, p < 0.001). Fractions of urine proteins L-FABP and I- FABP in sick vs. healthy children were also determined at a higher level (6.96±0.19 ng/ml and 1.01±0.25 ng/ml vs. 0.37±0.01 ng/ml and 0.1±0.02 ng/ml, respectively, at p < 0.001). The level of urine zonulin was increased (2.84±0.12 ng/ml) in sick vs. healthy children (0.17±0.04, p < 0.05). Conclusion. The study allowed to identify early markers of kidney and urinary tract damage (L-FABP, I-FABP, ZO) involved in developing inflammatory bacterial process, whereas measuring urine I-FABP, L-FABP, zonulin level can be used for non-invasive UTI diagnostics in infants and young children.