Perihilar FSGS

Perihilar variant of focal segmental glomerulosclerosis (FSGS). Hyaline deposition and sclerosis occur at the vascular pole of the glomerulus. This variant is believed to be a secondary form of FSGS, occurring as an adaptive response to other injuries resulting in loss of functioning nephrons, such as in obesity-related kidney disease. Images courtesy of Patrick Walker, MD.

Glomerulomegaly

A normal glomerulus (left) and hypertrophied glomerulus (glomerulomegaly, right). Glomerulomegaly is an adaptive response to decreased nephron number (e.g. prematurity) and/or increased demand (e.g. obesity). Patients with glomerulomegaly may have sub-nephrotic or nephrotic-range proteinuria, but other features of nephrotic syndrome are rare. Images courtesy of Patrick Walker, MD.

Endocapillary hypercellularity

A normal appearing glomerulus (left) compared to a glomerulus with endocapillary hypercellularity (right). Note the hypercellular capillary loop (red arrow) compared to the normal capillary lumens (black arrows). This histologic feature can be seen in several glomerular disorders, including IgA nephropathy, post-infectious glomerulonephritis, lupus nephritis, and C3 glomerulopathy. Images courtesy of Patrick Walker, MD.