Contributed by Anna Woodard, MD and Sheldon Bastacky, MD
18 year old male with microscopic hematuria of several weeks known duration. He has no family history of renal disease and is currently not taking any medications. On physical exam, his blood pressure is normal (115/70 mmHg) and he has no edema. A renal ultrasound shows the kidneys are of normal size and shape, bilaterally.
A renal biopsy was performed. A representative H&E is shown below.
Figure 1: Representative H&E. The two glomeruli are normocellular and normal-sized and significant tubular or interstitial abnormalities are noted.
Immunofluorescence microscopy was performed and a representative image of C3 is shown below.
Figure 2: Immunofluorescence staining with C3 shows focal, weak to moderate intensity staining in a coarsely granular pattern in the glomerular basement membrane.
Electron microscopy shows electron dense material focally expanding short stretches of the glomerular basement membrane lamina densa and lamina rara interna (Figures 5-7). Similar electron dense material is also present in mesangial areas, Bowman's capsule and the tubular basement membrane (Figures 8 and 9). Most of the glomerular basement membrane appears normal.