Urinary Cytokines as Biomarkers in Glomerular Diseases

Diagnosis of glomerular diseases is based on renal biopsy, an invasive method that offers information about the type and severity of renal damage and predicts renal function outcome. Types of glomerulonephrities differ in etiology, pathogenesis, type of cell involvement, immune reactions, and subsequently in the disease outcome. During evolvement of the disease cytokines, chemokines, growth factors are produced by native of infiltrating kidney cells and excreted in the urine. These molecules may serve as biomarkers and may provide useful information in diagnosis, prognosis and response to treatment. An ideal biomarker should be easily collected and measured and have high sensitivity and specificity. Particular cytokines may have central roles in glomerular diseases. IL-6, MCP-1, IL-1β and EGF urinary excretion can predict renal function outcome in IgA nephropathy. Metaloproteinases, A1 antitrypsin, Tamm-Horsfall protein, MCP-1 and other molecules have been used in the discrimination between focal segmental sclerosis and minimal change disease, in predicting relapse of FSGS after transplantation and response to treatment. Recent patents have established measurement of urinary cytokines in follow up and treatment of renal diseases.