SU2M - Renal Vascular Disease

Question 0

2 Causes of renal artery stenosis?

Answer 0

1. Atherosclerosis:
   - cause of 2/3rds of the cases
   - usually seen in elderly men
   - bilateral in 1/3 of pts
   - predisposing factors = smoking & high cholesterol levels
2. Fibromuscular dysplasia
   - usually seen in younger females
   - bilateral in 1/2 pts

Question 1

What is the most common cause of secondary HTN?

Answer 1

-renal artery stenosis

Question 2

3 Clinical features in pts with renal artery stenosis?

Answer 2

1. HTN –> sudden onset in a pt w/out family Hx, can be severe, usually refractive to HTN meds
2. Decreased renal function
3. Abdominal bruit –> present in 50-80% of pts, esp w/ fibromuscular hyperplasia

Question 3

4 Options for dx of renal artery stenosis?

Answer 3

1. Renal arteriogram = gold standard
   - contrast dye can be nephrotoxic in pts with renal failure
2. MRA
   - magnetic dye used that is NOT nephrotoxic (can be used in renal failure pts)
3. Duplex Doppler ultrasonography of renal arteries
4. Contrast enhanced CT scan

Question 4

Renal artery stenosis: tx?

Answer 4

1. Revascularization with percutaneous transluminal renal angioplasty (PRTA)
   - initial tx
   - high success rate (esp with fibromuscular type)
2. Bypass surgery
   - if PRTA fails
3. Conservative tx = ACEi, CCBs
   - can be used alone, or with revascularization procedures

Question 5

When can renal vein thrombosis be seen (6)?

Answer 5

1. Nephrotic syndrome
2. Invasion of renal vein by renal cell carcinoma
3. Trauma
4. Pregnancy/oral contraceptives
5. Extrinsic compression
6. Severe dehydration

Question 6

Clinical features of renal vein thrombosis (5)?

Answer 6

1. decreased renal perfusion
2. flank pain
3. HTN
4. Hematuria
5. Proteinuria
   * *depends on acuity and severity

Question 7

What is the second most common cause of ESRD?

Answer 7

-Nephrosclerosis due to HTN

Question 8

Hypertensive nephrosclerosis: definition

Answer 8

• systemic HTN increases capillary hydrostatic pressure in the glomeruli
• leads to benign or malignant sclerosis

Question 9

Benign nephrosclerosis: cause? Characteristics? What can it lead to?

Answer 9

• long-standing HTN can cause thickening of the glomerular afferent arterioles
• characteristics:
  1. mild-moderate increase in Cr levels
  2. microscopic hematuria
  3. mild proteinuria
• can eventually lead to ESRD if severe enough

Question 10

Malignant nephrosclerosis: cause? Characteristics? Who is it more common in?

Answer 10

• can be caused by long-standing benign HTN, or in a previously undiagnosed pt
• who: seen more often in African-american men
• characteristics:
  1. rapid decrease in renal function
  2. accelerated HTN

Question 11

Malignant nephrosclerosis: clinical manifestations?

Answer 11

1. Very high bp - w/ papilledema, cardiac decompensation, CNS findings
2. renal manifestations - ex: rapid increase in Cr, proteinuria, hematuria, RBC & WBC casts in urine sediment & nephrotic syndrome
3. microangiopathic hemolytic anemia - can also be present

Question 12

Hypertensive nephrosclerosis: tx?

Answer 12

1. control BP

2. in advanced disease, tx CKD

Question 13

Scleroderma and renal disease?

Answer 13

-in rare cases, can cause malignant HTN –> can lead to HTN nephrosclerosis

Question 14

Sickle cell nephropathy: what is it? tx?

Answer 14

• sickled RBCs can cause infarction, esp in microvasculature
• occurs most often in the renal papille
• recurrent infarction –> papillary necrosis –> renal failure &/or high frequency of UTIs
• nephrotic syndrome can develop –> can lead to renal failure
• *ACEi may be helpful