Fibrillary glomerulonephritis.

The occurrence of fibrillary glomerulonephritis is unusual in Taiwan, whereas it occurs in approximately 1% of renal biopsy specimens taken in the United States of American. This disease is characterized by extracellular randomly arranged non-branching Congo red-negative microfibrils within glomeruli. The microfibrils are less than 30 nm in diameter, and electron microscopy is essential for diagnosis. Differential diagnosis of the deposition of extracellular non-branching microfibrils within glomeruli is important because discrete diseases have different therapeutic and prognostic implications. The report will discuss two cases of biopsy-proved fibrillary glomerulonephritis who presented with proteinuria, hematuria, renal insufficiency, and hypertension. It is noteworthy that the renal function persistently went downhill, even though the physician treated the patients with corticosteroids, pulse treatment and immunosuppressive agents.