Vascular Diseases of the Kidney

Question 1

Vascular Diseases of the Kidney

Answer 1

Hypertension
- Nephrosclerosis

Thrombotic Microangiopathies

Atherosclerosis
- Renal Artery Stenosis

Question 2

Systemic vascular diseases

Answer 2

(hypertension, vasculitis, atherosclerosis, thromboembolic) can have major effects on kidney function.

Large blood vessels
Small blood vessels
Capillaries

Question 3

Nephrosclerosis

Answer 3

process not a diagnosis

Sclerosis of renal arterioles and small arteries –>

Narrowing of vascular lumens result in focal ischemia –>

Ischemia leads to glomerular sclerosis and chronic tubulointerstitial injury –>

Renal cortical atrophy and reduced renal function

Question 4

Nephrosclerosis

Answer 4

benign:
Associated with mild to moderate hypertension
Associated with aging
uncommonly leads to renal insufficiency.

Accelerated nephrosclerosis (malignant)
 severe hypertension (>200/120 mm)
elevation of plasma renin
The syndrome ( hypertensive crises) is a medical emergency requiring aggressive prompt antihypertensive therapy

Question 5

Nephrosclerosis- accelerated (malignant hypertension)- clinical presentation

Answer 5

Papilledema, retinal hemorrhages, encephalopathy and renal failure

Fundamental lesion is vascular injury - Hyperplastic arteriolitis

flea-bitten appearance

Question 6

Nephrosclerosis key concepts

Answer 6

commonly w/ hypertension

luminal reduction of renal vasculature –> glomerulosclerosis–> interstitial fibrosis and tubular atrophy

Question 7

Thrombotic microangiopathies

Answer 7

commonly caused by Thrombotic thrombocytopenia purpura (TTP)
Hemolytic uremic syndrome (HUS)

Pathogenesis: endothelial cell injury or platelet activation/ aggreatation. From bacterial toxins, cytokines, viruses, drugs, anti-endothelial antibodies

Question 8

Microangiopathic hemolytic anemia descriptive term for

Answer 8

mostly a hemolytic-anemia resulting from intravascular red blood cell fragmentation that produces schistocytes on the peripheral blood smear; resulting from abnormalities in the micro-vasculature including small arterioles and capillaries.

Question 9

Microangiopathic hemoltic anemia Peripheral Blood Films

Answer 9

• schistocytes, fragmented RBCs, decreased platelets

Question 10

Thrombotic microangiopathy lab studies and related organs

Answer 10

Microangiopathic hemolytic anemia smear
Thrombocytopenia

Multi-organ disease

Rhabdomyolysis
Acute respiratory distress
Pancreatitis
Hepatitis
Encephalopathy

Question 11

Thrombotic Microangiopathy Syndromes (TMA)

Answer 11

Arteriole occlusion with endotheliosis and lumen and vessel-wall fibrin

• Thrombocytopenic purpura (hereditary and acquired)
• Hemolytic uremic syndrome

can be shiga toxin-mediated TMA

Question 12

Thrombotic Thrombocytopenia Purpura

Answer 12

Multisystem disease

Classic symptoms
Thrombocytopenia
Hemolytic anemia 
Neurologic dysfunction
Fever
Renal failure

Question 13

Thrombotic Thrombocytopenia Purpura

Acquired and Inherited

Answer 13

Acquired TTP is an autoimmune disorder caused by autoantibody inhibition of ADAMTS13 activity

Hereditary TTP is caused by von Willebrand factor–cleaving protease mutation
- initial presentation typically in children

Question 14

Hemolytic Uremic Syndrome- typical

Answer 14

(Shiga-like toxins)

Characterized by hemolytic anemia, acute renal failure and thrombocytopenia
More common in children

The Shiga-toxin-activated endothelial cells becomethrombogenic

coagulation factors not consumed.

Compared to TTP, kidneys more severely affected

Question 15

Hemolytic Uremic Syndrome- Atypical

Answer 15

(excessive activation of complement)

Characterized by hemolytic anemia, acute renal failure and thrombocytopenia

defective complement activation regulatory proteins

hereditary or acquired

generally poor outcomes

Question 16

Drugs are also suspected of inciting thrombotic microangiopathy:

Answer 16

drug-dependent antibodies or direct tissue toxicity

quinine, cyclosporine, tacrolimus.

Question 17

Unilateral Renal Artery Stenosis

Answer 17

Goldblatt kidney)
Causes systemic hypertension by increased production of rennin from ischemic kidney

Atherosclerosis is most common cause of renal artery stenosis

Question 18

Bilateral Renal Artery Stenosis

Answer 18

Common cause of chronic ischemia and renal insufficiency in older patients
Not always associated with hypertension

Question 19

Fibromuscular Dysplasia

Answer 19

Causes 25% Renal Artery Stenosis

Most cases affect internal carotid or renal arteries)

Characterized by fibrosis or fibromuscular thickening involving the intima, media or adventitia of the artery

signs/ symptoms:
hypertension
cervical bruit
abdominal bruit
** transient ischemic attack/ stroke

Question 20

Renal Infarction

Answer 20

Kidneys are common sites for cortical infarcts

Large blood flow with limited collateral circulation

Question 21

Sickle cell nephropathy

Answer 21

commonly associated with hematuria and hyposthenuria (diminished concentrating ability)

Patchy papillary necrosis

Question 22

Diffuse Renal Cortical Necrosis

Answer 22

Present with abrupt onset of oliguria/anuria
Gross hematuria
Flank pain
Hypotension

Associated with catastrophic obstetric emergencies
Placental abruption (massive hemorrhage)
Sepsis with disseminated intravascular coagulation