Glomerular Pathology Flashcards
glomerulus cell types
- endothelial
- smooth muscle & mesangial
- epithelial (parietal + visceral)
mesangial cells
specialized smooth muscle cells that reside around capillaries
- phagocytic
- contract/relax to regulate flow
parietal epithelial cells
creates Bowman’s space for filtration collection
visceral epithelial cells
podocytes; specialized cells within Bowman’s space that form foot processes around the capillaries
clinical signs of glomerulopathy
proteinuria
may also see hypertension and hyper-coagulability
nephrotic syndrome
proteinuria
peripheral edema
hyperlipidemia
what types of stains are used to evaluate renal biopsies
H&E, PAS, JMS, MT, congo-red
glomerular responses to injury
- hypercellularity
- basement membrane thickening
- hyalinosis
- sclerosis
- synechia
hypercellularity
- proliferation of mesangial or epithelial cells
- infiltration of leukocytes
- formation of crescents
crescents
proliferation of podocytes and accumulation of leukocytes
basement membrane thickening
caused by increased synthesis of BM proteins and additional layers of BM matrix
hyalinosis
accumulation of plasma proteins within glomerulus
appears as extracellular, amorphous, eosinophilic material
sclerosis
deposition of extracellular collagenous matrix
can be mesangial only
can take over capillary lumen
synechia
parietal cells (Bowman’s capsule) adhere with visceral cells (podocytes) causing the attachment of the capillary wall to the basement membrane
occurs secondary to damaged podocytes
main cause of glomerulopathy in proteinuric dogs
immune complex glomerulonephritis
categories of glomerular disease
- immune complex glomerulonephritis
- non-immune complex glomerulonephritis
types of immune complex glomerulonephritis
- membranoproliferative glomerulonephritis
- membranous glomerulonephropathy
membranoproliferative glomerulonephritis (MPGN)
sub-endothelial immune complex deposits
causes INCREASED glomerulus size and cellularity
causes increased mesangial matrix leading to DM duplication
membranous glomerulonephropathy (MGN)
sub-epithelial immune complex deposits
NO increased cellularity
causes holes and spikes in basement membrane
non-immune complex glomerulonephritis
- glomerulosclerosis
- amyloidosis
glomerulosclerosis
increase in extracellular matrix with collapse of capillary lumen
can be primary or secondary
can be segmental or global
amyloidosis
protein folding disorder causing protein deposits in glomerulus
often concurrent proteinuria
glomeruli expanded by smudgy, pink material
