what are mesangial cell and what is their function
smooth muscle–like cells that contain actin and myosin -> they connect to each other via gap junctions and to the Glomerular Basement Membrane via cell processes;
Contraction of mesangial cells regulates the size of the capillary lumen and thus the amount of glomerular blood flow
what is a focal glomerulonephritis
affecting only some glomeruli
what is a diffuse glomerulonephritis
affecting all glomeruli
what is a segmental glomerulonephritis
affecting only one part of the glomerulus
what is a global glomerulonephritis
affecting the whole glomerulus
what is proliferation
increase in number of cells
what is cell expansion
increase in intracellular matrix
what is crescent proliferation
proliferation of cells within the bowman’s space
2 mechanisms underlying glomerulonephritides
types of immunological glomerulonephritides + examples !!! (4)
brief pathophys of goodpasture’s disease
antibodies against T4 collagen -> T4 collagen is used to form the basement membrane => destruction of glomerular basement membrane
what is “pauci-immune” crescentic glomerulonephritis
an idiopathic form of crescentic glomerulonephritis that typically lacks significant deposits within glomeruli and most often is associated with ANCA -> systemic vasculitis
indications for renal biopsy (6)
might not biopsy in last 2
complications of renal biospy (2)
contraindications to renal biopsy
what imaging guidance is used in renal biopsies
ultrasound
what does the EM of minimal change disease biopsy show
fusion of podocyte foot processes -> biopsy looks normal on light microscopy so EM must be done
what drug class is often implicated in minimal change disease
NSAIDs
what malignancy is often implicated in minimal change disease
lymphoma; leukemia
how does focal segmental glomerulosclerosis present
with nephrotic syndrome and renal impairment
what is seen on biopsy of focal segmental glomerulosclerosis (if correct area taken)
segmental sclerotic lesions with C3 and IgM deposition
if nephrotic syndrome doesn’t improve with steroids, what underlying cause should be suspected
what can FSGS and membranous nephrapthy progress to
CKD
secondary causes of focal segmental glomerulosclerosis (4)