Renal Disorders Flashcards
(52 cards)
What are intrinsic renal processes causing AKI that are ischemic in origin?
- GN
- Renovascular Disease
- Rhabdomyolysis
- Hepatorenal syndrome
- CIN
These processes are associated with reduced renal blood flow (RBF) and may have low urinary sodium concentration and fractional excretion of sodium (FE Na) < 1%.
What is a lacunar stroke?
Ischemic stroke involving small arteries penetrating deep brain structures
This type of stroke can lead to significant neurological deficits.
What elements of urine analysis (UA) are consistent with diabetic nephropathy (DN)?
- Proteinuria
- Lack of active sediment (cellular elements)
Active sediment may include red blood cells or casts, which are less common in DN.
What percentage of diabetic nephropathy cases show hematuria?
30%
RBC casts are seen in about 10% of cases.
What is the leading cause of end-stage renal disease (ESRD) in the U.S.?
Diabetic nephropathy (DN) – ‘nephrosclerosis’
25% of renal transplants in the U.S. are performed due to DN.
Which parts of the nephron are primarily affected in diabetic nephropathy?
- Glomerulus
- Tubular Interstitium
Changes include interstitial fibrosis and thickening of the tubular basement membrane.
What is the function of the glomerulus?
To filter plasma
This is a critical function in the renal system, essential for waste removal.
What are the three parts of the glomerulus that make up the filtration barrier?
- Fenestrated glomerular capillary endothelium
- Basement membrane
- Foot processes of the visceral epithelium (podocytes)
These components work together to allow selective filtration.
What is the effect of glycation of the efferent arteriole basement membrane in diabetic nephropathy?
It leads to efferent arteriole hyaline arteriosclerosis and increased GFR due to reactive afferent arteriole vasodilation
This is associated with stage 1 ‘Hyperfiltration’ in DN.
What is the mesangium?
Space outside the capillary lumen contiguous with the smooth muscles of the arterioles
It consists of cells and acellular matrix.
What are the clinical characteristics of diabetic nephropathy (DN) in terms of urine analysis?
- Glycosuria
- Proteinuria
- Early: microalbuminuria (30-300 mg/day)
- Later: macroalbuminuria (> 300 mg/day)
The amount of proteinuria correlates with the incidence of ischemic heart disease (IHD) and stroke.
What is the biphasic change in GFR observed in diabetic nephropathy?
Initially increased GFR (stage 1), then decreased GFR (stages 3 + 4)
This reflects the progression of kidney damage over time.
What treatments are pillars of management for diabetic nephropathy?
- Tight BP control
- Tight glycemic control (A1c < 7.0%)
- Treatment of dyslipidemia
- Treatment with an ACE inhibitor or ARB
These treatments aim to slow the progression of nephropathy.
What do ACE inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) do in diabetic nephropathy?
They slow the progression of DN and proteinuria
They are effective in both type 1 and type 2 diabetes patients.
What is the role of SGLT-2 inhibitors in diabetic nephropathy?
They decrease the incidence of major adverse cardiac events (MACE) in patients with type 2 DM and ischemic heart disease (IHD)
Examples include empagliflozin, canagliflozin, and dapagliflozin.
What is acute interstitial nephritis (AIN)?
AKI characterized by interstitial inflammation and edema that spares the glomeruli
AIN accounts for 5-15% of all causes of AKI.
What is the differential diagnosis (DDx) for acute interstitial nephritis (AIN)?
- Drugs (75%)
- Infections (15%)
- Idiopathic (5%)
- Autoimmune Disorders
- Systemic Disorders
Drug-induced AIN is the most common cause.
What is the usual time interval between drug exposure and presentation of acute interstitial nephritis?
Mean latent period is 10 days
This is shorter compared to NSAIDs, where the latent period can be months.
What is Tubulointerstitial Nephritis with Uveitis (TINU)?
AIN with uveitis
Uveitis is inflammation of the uvea, the pigmented layer below the sclera and cornea.
What is a potential renal complication associated with Hantavirus?
Granulomatous interstitial nephritis
Granulomatous interstitial nephritis is characterized by aggregates of macrophages and is often linked to chronic inflammatory processes.
What does AIN stand for?
Acute Interstitial Nephritis
What is Tubulointerstitial Nephritis with Uveitis (TINU)?
AIN with uveitis
What are the usual presenting complaints of AIN?
- Malaise
- Anorexia
- Nausea/vomiting
- Oliguria
- Acute Kidney Injury (AKI)
What laboratory findings are commonly seen in AIN?
- Pyuria
- Eosinophilia
- Urine eosinophils
