Background: The normal glomerular basement membrane, composed of type IV collagen, plays an important function in the process of filtration. Rarely, type III, type I, or type V collagen is seen in the glomerulus, resulting in three different types of non-immune mediated glomerulopathies recognized thus far. These are characterized by deposition of banded collagen fibers in the glomerulus.
Methods: The authors reviewed 4934 kidney biopsies submitted over the past 5 years. Five of these revealed the presence of banded collagen in the glomeruli.
Conclusion: Combined clinical and ultrastructural examination has led to a definitive diagnosis. These diseases exhibit indolent progression and as yet do not have specific treatment.