Fibrillary glomerulonephritis: A retrospective analysis of a case series from a tertiary center

Fibrillary glomerulonephritis is a rare diagnosis, and guidance on diagnosis and management is scant. We present a case series of patients with fibrillary glomerulonephritis from University Medical Center Ljubljana.

We conducted a retrospective analysis of patients with the diagnosis of fibrillary glomerulonephritis since 2006. We analyzed data on clinical presentation, treatment modalities, and kidney survival. For a subset of patients, data on DNAJB9 staining and markers of complement activation were also available.

We included 17 patients with fibrillary glomerulonephritis, 59% female, with a median age of 61 years (range 33 - 71). The most common clinical presentation was asymptomatic proteinuria with preserved kidney function (41%). Eight patients had complement activity testing performed, which revealed elevated serum C5b-9 at least at 1 time point in 5 patients (63%). One patient had positive anti-factor H antibodies, and 2 patients had positive anti-C1q antibodies. Nine patients had available staining results for DNAJB9, which was positive in all 9 cases. The median time of follow-up was 12 months. The most common form of treatment was with corticosteroids in 8 patients, followed by rituximab in 5 patients. Seven patients (41%) had at least partial remission with stabilization of kidney function, 8 patients (47%) reached end-stage kidney disease during follow-up. Due to the small number of patients, analysis of impact of treatment on kidney survival was not performed.

Fibrillary glomerulonephritis is a heterogenous disease, and a significant number of patients present with a slowly progressive disease, warranting long-term treatment. New treatment strategies are necessary.