Fibrillary glomerulonephritis (FGN) remains one of the least-studied glomerular diseases in nephrology, accounting for less than 1% of kidney biopsies and offering clinicians few evidence-based treatment options.

Andrew Bomback, MD, MPH, opens the segment by asking Gerald Appel, MD, how he defines a non-responder in fibrillary glomerulonephritis (FGN) in practice, how long patients should remain on therapy, and what numbers signal that treatment is not working.