05.20 - Diabetic Renal Disease (Wall, Nichols) - PP Flashcards
Stage 2 of DN
Clinically evident: Micro-albuminuria, BP rises, glomeruli show damage
Which is specific for diabetic glomerulopathy: Capsular Drops, Fibrin Caps
Capsular Drops
Globally sclerotic glomeruli, dilated tubules resembling thyroid follicles, interstial fibrosis
Microscopic appearance of end stage kidney in DN
Stage 4 of DN
GFR < 75mL/min - HTN ubiquitous
Stage 3 of DN
Macro-Albuminuria, Creatinine and BUN levels rise, BP rises
Development of ___ heralds rapdid decline in GFR in Type2 DM
Macroalbuminuria
Condition that will cause Hyaline Sclerosis in both efferent and afferent arterioles
DM
% of diabetics who develop nephropathy
30-40%
By the time of Macroalbuminuria (over nephropathy), over 90% of patients have
HTN
Features of Nodular Type Diabetic Glomerulopathy
Kimmelstiel Wilson nodules and Hyaline sclerosis of both arterioles
Macroalbuminuria is defined as
random urine albumin/creatinine over 300 mg/g
Patients taking ACEi’s or ARB’s should be monitored for
Hyperkalemia
End Stage kidney from Diabetic Nephropathy looks just like
HTN Nephropathy
Nodular Glomerulosclerosis (Kimmelstiel Wilson Disease) correlates with
Renal failure eventually requiring dialysis
How do you distinguish diabetic nephropathy from most other forms of CKD
Glomeruli and kidneys are typically normal or larger in DN; in others, renal size is usually reduced
How does Glucose lead to Glomerular Pressure increase
Glucose provides osmotic diuretic effect –> Incr renal filtration –> Glomerular hypertophy –> Glomerular pressure incr
Diffuse type Diabetic Glomerulopathy consists of
Capillary BM thickening; Increased MM
Macroalbuminuria is aka
Overt Nephropathy
Micro-Albuminuria is defined as
> 30 mg/g loss
How does glucose lead to Premature Glomerulosclerosis
Osmotic Diuretic Effect –> Incr filtration –> G pressure incr –> Hypertrophy –> G cell failure –> Premature Glomerulosclerosis
Most common type of Diabetic Glomerulopathy
Diffuse
What causes injury to tubular cells in Glomerular HTN
G HTN –> Injury to GBM –> Leaks plasma proteins –> Attempts to reabsorb these proteins injures tubular cells
What causes fibrosis and scarring in Glomerular HTN
Tubular inflammation and renal microvascular injury from protein leakage
Reduction in proteinuria is associated with
Reduced risk for ESRD
Where do fibrosis and scarring occur in Glomerular HTN
Both glomerular and tubular elements of nephron
Kimmelstiel Wilson nodules and Hyaline sclerosis of both arterioles
Features of Nodular Type Diabetic Glomerulopathy
Which drug has been shown to slow rate of diabetic nephropathy more than others
ACEi
Fibrin caps
Crescentic deposits of condensed leaked plasma proteins
Avg time to progression from stage 1 to stage 4 in DM1
17 years
Higher baseline Albuminuria =
Faster rate of progression
Microscopic appearance of end stage kidney in DN
Globally sclerotic glomeruli, dilated tubules resembling thyroid follicles, interstial fibrosis
At what stage of DN is the condition essentially irreversible?
Stage 4
Stage 5 of DN
GFR less than 10 (ESRD)
___ is marker for increased CV risk in DN
Microalbuminuria
Fasting blood glucose criteria for DM
126 mg/dL
Anti-hypertensives to use in diabetics
ACEi’s and ARB’s
TGF-beta has been implicated in many ___ diseases
Chronic, Scarring
T/F: Patients with macroalbuminuria are more likely to die than develop ESRD
TRUE
Diffuse type Diabetic Glomerulopathy is identical to that which occurs in
HTN and aging
What condition has Kimmelstiel Wilson nodules
Nodular Type Diabetic Glomerulopathy
Hyaline Sclerosis of Afferent and Efferent Arterioles in DM vs HTN
HTN causes hyaline sclerosis of afferent, whereas DM will affect both
Microalbuminuria in DN over time leads to
Overt Proteinuria, Reduced GFR, HTN
What starts the clinical phase of DN
Overt Proteinuria
Tubular inflammation and injury from Glomerular HTN activates pathways that lead to
Fibrosis and Scarring
At what stage of DN do patients require dialysis or transplantation
Stage 5
Where in glomerulus do Kimmelstiel Wilson nodules occur
Periphery of Glomerular Tuft
For almost all kidney disease, including DN, likelihood of dying from what is higher than reaching ESRD
CV disease
Top 2 causes of ESRD
Diabetes (43%), HTN (23%)
Which type of Diabetic Glomerulopathy is characteristic (specific) for DM
Nodular Type
Where in glomerulus do Fibrin Caps occur?
Overlying peripheral capillaries
Classic symptoms of hyperglycemia
Thirst, Polyuria, Poldipsia, Visual Blurring
What occurs earlier than microalbuminuria in DN
Changes to GBM structure (collagen IV deposition)
Why does RAAS play a role in diabetic nephropathy
Inefficient at shutting down RAAS production
How is Albuminuria calculated
Albumin / Creatinine to correct for diffs in urine concentration
At what stage of DN does kidney demonstrate an inability to adequately filter wastes
Stage 3 - Creatinine and BUN rise
Stage 1 of DN
Hyperfiltration - Kidney incr in size
___ lower both arterial BP and glomerular capillary pressures
ACEi’s and ARBs
What causes inflammation in tubular cells in Glomerular HTN
G HTN –> Injury to GBM –> Leaks plasma proteins –> Attempts to reabsorb these proteins injures tubular cells –> Inflammation
Nodular Type Diabetic Glomerulopathy occurs after how many years
10
Kimmelstiel Wilson nodules eventually
squeeze capillaries shut
Where in glomerulus do Capsular drops occur
Parietal layer of Bowman’s Capsule protruding into urinoferous space
Once in ____, patient is unlikely to regress
Overt Proteinuria (macroalbuminuria)
2 types of Exudative lesions
Fibrin Caps, Capsular Drops
Most common cause of kidney failure
DM
ACEi’s have been show to lower BP and also reduce ___
Microalbuminuria (lower glomerular capillary pressure)
Avg time to progression from stage 1 to stage 5 in DM1
23 years
Capsular Drops
Deposits of partly plasma proteins, and partly basment membrane
On which arteriole does Ang2 selectively act?
Efferent –> Incr intraglomerular pressure
Deposits of partly plasma proteins, and partly basment membrane
Capsular Drops
Diabetics Microvascular Complications are eliminated if patient obtains optimal management of glucose, BP, and lipid levels
FALSE
Effects of Glomerular HTN
Injury of GMB –> Leak proteins –> Injury to tubular cells and inflammation
First clinically detectable abnormality of DN
Microalbuminuria
Outcome of increased glomerular pressure and subsequent hypertrophy
Premature Glomerulosclerosis
How does TGF-beta get activated? What is consequence?
Ang2 –> TGF-beta –> Proliferation of fibroblasts and tubuloepithelial cells –> Hypertrophy, BM thickening, MM expansion
Gross appearance of End stage kidney in Diabetic Neprhopathy
Diffuse fine granularity of cortical surface = Nephrosclerosis
Crescentic deposits of condensed leaked plasma proteins
Fibrin caps
3 histological features of DN
Incr MM, Glomerular Collapse, Glomerulosclerosis
___ reduction determines CV outcome
Proteinuria
Effect of Ang2 in DN
Selective constriction of efferent>afferent –> Incr SNGFR –> Incr intraglomerular pressure –> Glomerular HTN