Urinary levels of interleukin-6 and disease activity in patients with IgA nephropathy.

We studied, using ELISA, 27 patients with IgA nephropathy to determine if levels of urinary interleukin-6 (IL-6) might reflect the disease activity. The levels of urinary IL-6 in patients with the advanced stage were significantly higher than those in patients with the mild stage of the disease or in healthy adults. The results showed a significant correlation between the levels of urinary IL-6 and the disease activity, i.e., levels of urinary cast and urinary protein. It was thus suggested that the measurement of urinary IL-6 is useful in evaluating the degree of glomerular injuries and/or prognosis in patients with IgA nephropathy.