Renal Biopsy Findings in 500 Patients with Hepatitis C Virus
Christie L Boils, Patrick D Walker, Christopher P Larsen. Nephropath, Little Rock, AR
Background: Hepatitis C virus (HCV) infection has been associated with several glomerular diseases including membranoproliferative-pattern glomerulonephritis (MPGN), membranous glomerulopathy, and fibrillary glomerulopathy. The relative frequency of these diseases in the setting of HCV has not been previously studied in a large case series, to our knowledge. Our aim was to determine the spectrum of renal biopsy findings in patients who are HCV-positive.
Design: By retrospective review, 500 patients with HCV infection who underwent native renal biopsy were identified. All cases were processed by light, immunofluorescence (IF) and electron microscopy. Only cases with adequate diagnostic material were included.
Results: The study group included 343 men and 157 women with a mean age of 53 years (range 14 to 81). Eighteen HCV+ patients had concomitant hepatitis B virus infection and 31 patients were positive for HIV. The most common diagnosis was diffuse and nodular diabetic glomerulosclerosis (DNDGS) (30%), followed by HCV-associated MPGN (20%), arterionephrosclerosis (9.4%), IgA nephropathy (6.2%), membranous nephropathy (5%), acute tubular injury (4.6%), primary focal segmental glomerulosclerosis (4.2%), and fibrillary glomerulopathy (2.6%). Almost twenty other primary findings were represented in the remaining 18% of cases. In patients with a clinical history of both HCV and DM, only 7% were found to have an HCV-associated GN. The primary indication for biopsy in the 100 patients with HCV-associated MPGN was proteinuria in 59% (mean 6.4 g/day), acute renal failure (38%), and hematuria (26%). Indications for biopsy in patients who proved to have DNDGS without an HCV-associated GN on biopsy were proteinuria (65%, mean 7.2 g/day), chronic kidney disease (20%), acute renal failure (9%) and hematuria (7%). In patients with MPGN, all 21 patients tested showed hypocomplementemia. IF most commonly had positive staining for C3 (92%) and IgM (89%) with mean intensities of 2.1 each (scale 0-3+), followed by IgG in 57% and IgA in 18% (mean intensity 1.6 and 1.8, respectively). Monoclonal light chain restriction was noted in 3 patients with MPGN (2 kappa, 1 lambda).
Conclusions: Renal biopsy revealed a spectrum of findings in patients with hepatitis C virus infection. The fact that DNDGS was the most common finding indicates that nephrologists struggle to differentiate these diseases clinically. Hypocomplementemia is typically present in HCV-associated MPGN, however it is not typically present in the other HCV-associated glomerulonephritides of membranous and fibrillary glomerulopathy.
Category: Kidney (does not include tumors)
Monday, March 19, 2012 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 251, Monday Morning