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Renal II Exam 2 > Vascular Diseases of the Kidney > Flashcards

Flashcards in Vascular Diseases of the Kidney Deck (22):
1

Vascular Diseases of the Kidney

Hypertension
- Nephrosclerosis

Thrombotic Microangiopathies

Atherosclerosis
- Renal Artery Stenosis

2

Systemic vascular diseases

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

Large blood vessels
Small blood vessels
Capillaries

3

Nephrosclerosis

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

4

Nephrosclerosis

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

5

Nephrosclerosis- accelerated (malignant hypertension)- clinical presentation

Papilledema, retinal hemorrhages, encephalopathy and renal failure

Fundamental lesion is vascular injury - Hyperplastic arteriolitis

flea-bitten appearance

6

Nephrosclerosis key concepts

commonly w/ hypertension
luminal reduction of renal vasculature --> glomerulosclerosis--> interstitial fibrosis and tubular atrophy

7

Thrombotic microangiopathies

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

8

Microangiopathic hemolytic anemia descriptive term for

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.

9

Microangiopathic hemoltic anemia Peripheral Blood Films

- schistocytes, fragmented RBCs, decreased platelets

10

Thrombotic microangiopathy lab studies and related organs

Microangiopathic hemolytic anemia smear
Thrombocytopenia

Multi-organ disease

Rhabdomyolysis
Acute respiratory distress
Pancreatitis
Hepatitis
Encephalopathy

11

Thrombotic Microangiopathy Syndromes (TMA)

Arteriole occlusion with endotheliosis and lumen and vessel-wall fibrin

- Thrombocytopenic purpura (hereditary and acquired)

- Hemolytic uremic syndrome

can be shiga toxin-mediated TMA

12

Thrombotic Thrombocytopenia Purpura

Multisystem disease

Classic symptoms
Thrombocytopenia
Hemolytic anemia
Neurologic dysfunction
Fever
Renal failure 

13

Thrombotic Thrombocytopenia Purpura
Acquired and Inherited

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

14

Hemolytic Uremic Syndrome- typical

(Shiga-like toxins)

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

The Shiga-toxin-activated endothelial cells become thrombogenic

coagulation factors not consumed.

Compared to TTP, kidneys more severely affected

15

Hemolytic Uremic Syndrome- Atypical

(excessive activation of complement)

Characterized by hemolytic anemia, acute renal failure and thrombocytopenia

defective complement activation regulatory proteins

hereditary or acquired

generally poor outcomes

16

Drugs are also suspected of inciting thrombotic microangiopathy:

drug-dependent antibodies or direct tissue toxicity

quinine, cyclosporine, tacrolimus. 

17

Unilateral Renal Artery Stenosis

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

Atherosclerosis is most common cause of renal artery stenosis

18

Bilateral Renal Artery Stenosis

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

19

Fibromuscular Dysplasia

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

20

Renal Infarction

Kidneys are common sites for cortical infarcts

Large blood flow with limited collateral circulation

21

Sickle cell nephropathy

commonly associated with hematuria and hyposthenuria (diminished concentrating ability)

Patchy papillary necrosis

22

Diffuse Renal Cortical Necrosis

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