[Fibrillary immunotactoid glomerulonephritis--an unusual cause of irreversible kidney failure].

Fibrillary-immunotactoid glomerulopathy (FITGP) is a rare cause of nephrotic syndrome. In this patient, male 65-years-old, respectively, fibrillary glomerulonefritis (FGN) was diagnosed by percutaneous renal biopsy. Clinically, the disease manifested with long term proteinuria and nephrotic syndrome without any associated systemic disorder. Histologically, glomeruli showed deposition of PAS+, fuchsinophilic and Orange G+ material in the mesangium and basal membranes. Strong granular immunofluorescent IgG, C3, kappa and lambda light chains deposition was present in the mesangium. Electronmicroscopically, depositions of fibrillary material in the expanded mesangium and in the peripheral basal membranes were found. Randomly distributed nonbranching fibrils measured 18-28 nm. After 18 months of follow-up, the therapy with corticosteroids and Cylosporin A was without effect, and the disease progressed into chronic renal failure, and after 24 months of biopsy the patient is undergoing hemodialysis now.