Risk factors for progression IgA-nephropathy in children

BACKGROUND. The course and outcomes of primary IgA nephropathy in children are variable. Early therapy for high-risk individuals can help to delay the development of end-stage renal disease.

THE AIM: to analysis of risk factors for progression and outcomes in children with IgA nephropathy, taking into account clinical and morphological data at the onset and during follow-up.

PATIENTS AND METHODS. A retrospective study of 75 children was carried out; the median follow-up was 28 months. The median age of onset was 9.1 years. Patients were divided into 2 groups: 1st – patients with idiopathic IgA nephropathy (n= 53), 2nd – patients with Shenlein-Henoch purpura (n = 22). The diagnosis of primary IgA nephropathy was morphologically confirmed in all patients. Nephrobiopsy data were classified according to the Oxford scale (MEST-C score). The age of onset and first-time admission, the level of proteinuria and glomerular filtration rate (GFR) at the onset, at 12 months, at the end of follow-up, mean arterial blood pressure, MEST-C score, medication before nephrobiopsy were investigated. Progression was determined as a decrease in GFR less than 60 ml/min/1.73 m². Outcomes were assessed by absence/presence of remission. We provided a search for factors influencing GFR at the end of the follow-up. Data analysis was performed using Student's t-test, Mann-Whitney, χ^2, Fisher, linear regression model, binary logistic regression.

RESULTS. Unlike adults, the predictive value of the MEST-C score in children has not been proven and is not associated with a decrease in GFR <60 ml/min/1.73 m². GFR at the end of follow-up was lower in the idiopathic IgA nephropathy group than in group 2. The use of multiple linear regression predicts GFR on average after 28 months of observation.

RESULTS. Unlike adults, the predictive value of the MEST-C scale in children has not been proven and is not associated with a decrease in GFR <60 ml/min/1.73 m². GFR at the end of follow-up was lower in the idiopathic IgA nephropathy group. The use of multiple linear regression predicts GFR on average after 28 months of observation.

CONCLUSIONS. The influence of morphological factors on the outcome and course of IgA nephropathy has not been proven. The level of GFR at the onset, mean blood pressure, and the age of the first-time admission turned out to be independent variables, which made it possible to identify children with an expected decrease in GFR less than 90 ml/min /1.73 m² to the group of specific outpatient follow-up.

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