Факторы риска и маркеры развития тубулоинтерстициального нефрита у детей с оксалатно-кальциевой кристаллурией

Research objective: to study the clinical and biochemical risk factors and markers for the formation of tubulointerstitial nephritis  in children with oxalate-calcium crystalluria. Methods: 30 children with tubulointerstitial nephritis were examined on a background  of oxalate-calcium crystalluria. Special clinical and laboratory methods of research were used: stable metabolites of nitric oxide-nitrites and activity of superoxide dismutase, albumin in urine were determined in erythrocytes and urine. To determine the clinical  features of the course and identify risk factors for the development of tubulointerstitial nephritis, we analyzed: perinatal and genealogical anamnesis, the age of debut of oxalate-calcium crystalluria and tubulointerstitial nephritis, and ultrasound data from the organs  of the urinary system. Results: In children with tubulointerstitial nephritis, in 22% of cases the signs of oxalate-calcium crystal-luria preceded the underlying disease. For tubulointerstitial nephritis, which occurred against the background of metabolic disturbances, whose debut occurred at an early age, a latent course is typical, and minimal tubular kidney dysfunction, formed at the age  of 4–11 years. The following clinical and anamnestic factors had the greatest impact on the formation of tubulointerstitial nephritis  from a single-factor analysis: a family history with family history and the presence of 2 degrees of kinship of urolithiasis, a threat of termination of pregnancy and gestosis of the first half of pregnancy, hyperechoic inclusions in the renal parenchyma by ultrasound examination of child. In parallel with the processes of antioxidant protection against the background of oxidative stress, there is an increase in the level of metabolites of nitric oxide in the urine, and in combination with albuminuria, an increase in endothelial dysfunction. Conclusion: the leading factors in the formation of tubulointerstitial nephritis in children with oxalate-calcium crystalluria are an  aggravated genealogical anamnesis due to the presence of urolithiasis in relatives of the first and second degree of kinship. According to the results of special research methods, albuminuria, low activity of superoxide dismutase in the urine, higher levels of nitric  oxide in erythrocytes and urine indicate the progression of tubulointerstitial nephritis and are markers of the inflammatory process.