Purpose. To determine the clinical significance of urinary excretion of the transforming growth factor (TGF–β1), angiotensin II (Ang II) and β2-microglobulin (β2-MG) in children with vesicoureteral reflux (VUR) for early detection and prognosis of the progression of reflux nephropathy (RN).
Material and Methods. Seventy-nine patients with varying degrees of VUR aged 1 to 14 years (mean age 5.69±0.44 years), 58 (73.4%) girls. Depending on the results of DMSA-scintigraphy and the application task, the patients were divided into the following groups: comparison group (group 1) – patients with different degrees of VUR without RN (n=12, mean age – 1.65±0.31 years), 8 girls (66.7%). The main group included 67 children with RN (5.64±0.81 years), and depending on the severity of RN was divided into 2 groups: group 2–27 children with mild (I-II) degree of RN (5.89±0.77 years), 19 (70.4%) girls, and group 3–40 children with severe (III-IV) degree of RN (5.41±1.07 years), 31 (77.5 %) girls. Depending on the course of RN, both groups were divided into subgroups: 2A (without progression of RN) – with RN of I-II degrees (n=16, mean age – 5.34±0.23 years), 11 (68.8%) girls; 2B (with progression of RN) – with RN of I-II degrees (n=11, mean age 6.43±0.86 years), 8 (72.7%) girls; 3A (without progression of RN) – with RN of III-IV degrees (n=18, mean age – 6.17±0.55 years),14 (77.8%) girls; 3B (with progression) – with RN of III-IV degrees (n=22, average age – 4.65±0.45 years),17 (72.3%) girls; group 4 (control) 20 apparently healthy children (6.24±0.31 years), 12 (60%) girls. The study groups of patients did not differ significantly in sex and age. All children underwent examination of urinary excretion of AngII, TGF-β1, β2-MG in the morning urine and revaluation results to urinary creatinine level.
Results. The urinary levels of AngII, TGF-β1, β2-MG were significantly higher in the groups of children with RN than in the control group. Increase in Ang II and TGF-β1 levels was significantly higher in the main group than in the comparison group (P<0.05). The most sensitive markers for early detection of RN are AngII and TGF-β1; glomerular filtration rate (GFR) and β2-MG reflect the progression of RN. Reduction in GFR is an unfavorable and more characteristic sign for a severe degree of RN and for its progressive course.
Conclusion. The direct correlation revealed between the level of excretion of the studied pro-fibrogenic factors and the development of RN indicates the advisability and potentials for their inclusion as diagnostic markers of early detection of RN. The urinary β2-MG level is more reflective of the progressive course of RN.

Keywords: markers of sclerosing, reflux nephropathy, vesicoureteral reflux