The Kidney and Hypertension

Question 1

Renal causes of HTN

Answer 1

Abnormalities in primary
Parenchymal dz
Vascular dz

Question 2

Renal damage from HTN

Answer 2

Progression of chronic
Benign HTN nephrosclersis
Malignant nephroscleoriss

Question 3

Salt sensitivie kidney

Answer 3

No matter how high the CO or TPR is, renal excretion has the capacity to return BP to normal

Therefore maintenance of crhonic HTN requires renal participation

Maybe result of decreased ability to excrete Na load…a higher AP required to maintan Na balance

Question 4

Salt wasting disorders

Answer 4

Associated with low BP disorders

Question 5

Salt sensitivity

Answer 5

High salt intake correlate with increase prevalene of ess HT

INceease sensitivity due to genetics…more in AA

Question 6

OTher causes of salt-sensitive HTN

Answer 6

Low brith weight (nephron underdosing)

Primary glomerular dz

Aging, diabetes, obesity

Question 7

Secondary HTN causes

Answer 7

Monogenetic tubular defects (Liddle syndrome)

Renal parenchymal
renal vascular dz

Question 8

Renal parenchymal dz

Answer 8

Leading cause of HTN

RPomotes HTN and HTN promotes progression of kidney dz

Question 9

Circle of HTN and kidney

Answer 9

Primary dz…dec neprhon number…hypertrophy and vasodilation of sruving neprhon and increased pressure…increase GFR and pressure…increase glomerular scelorisis…decrease neprhon number

COnstriction of the efferent arteriole and dilatio nof afferent to increase the pressure

Question 10

Vascular causes of renal HTN

Answer 10

Ateromatous renal artery stenosis and fibromuscular renal artery hyperplasia

Question 11

Renovascular HTN

Answer 11

Most commonly atherscelorsis

Less common fibromuscular dysplasia

Question 12

Renovascular HTN clinical

Answer 12

Onset under 30 or over 55

SUdden onset uncontrolled in previously well controlled

Accelerated/malignant HTN

Intermittnet pulm edema

Epigastric bruit, particularly systolic/diastolic

Azotemia induced by ACEI

Unilateral small kdiney

Unexplained hypokalemia

Question 13

Stensosi effects

Answer 13

INcreased renin…goes to AT2…Vasoconstriction, renal sodium retention, aldosterone secretion

Constricts efferent arteriole to help increase the GFR

Question 14

Unilateral renal artery stenosis

Answer 14

Reduced perfusion…increased in RAAS system in that side…leads to increased renal perfusion in the ther kidney (increased Na excretion and suppressed RAS)

Question 15

Effect of RAS blockade

Dx tests

Unilateral renal artery stenosis

Answer 15

Reduced AP, enhanced lateralization of diagnostic tests, GFR in stenotic kidney may fall

Plasma renin activity elevated
Lateralized features

Question 16

ACEI effect in affected unilaterla renal steoniss dz

Answer 16

Will drop the GFR by dilating the effernt artieole

Question 17

Bilateral renal stenosis path

Answer 17

Bilateral…reduced perfusion…activated RAS and impaired Na and water excretion…volume expansion so RAS is then turned off…then increased arterial pressure

Question 18

Effect of blockade and dx tests of bilateral

Answer 18

Reduced arteril pressure only after volume depletion..may lower the GFR

Dx - plasma renin activity normal or low and no lateralized features

Question 19

Renovascular HTN dx

Answer 19

Duplex doller US, CTA, MRA

Question 20

Fibromuscular dysplasia

Answer 20

Young female 15-40

Medial in 90% and often in distal RA

Tx (PTRA) - successful in most…restenosis in 5-11, cured in 60

Total occlusion rare

Question 21

Atheroscleotic RAS

Answer 21

Usually men over 55

ESRD in 11%

Progressesi n more than half

Tx is emphasis on medical managmenet…stent success is very high but cure is low

Question 22

Medical rx of renovascular HTN

Answer 22

Aggressive risk fx mods

ACEI/ARB safe in unilateral if careful…but contraindiciated in bilateral RAS or solitary kidnye RAS

Question 23

HTN nephrosclerosis

Answer 23

Due to HTN damage ot renal vasculature

Abnormalities in walls of small pre-glomeraular arterioles

Patchy ischemic atrophy gloemruli and less extent in the tubules

Slowly progressive renal failure

Question 24

HTN neprhosclerosis demographics

Answer 24

Not everyone

Tx early on may help and less common than other HTN complications

Question 25

Factors of developemnt of NTH neph

Answer 25

Degree of HTN Transmission of pressure to glom Tissue susceptibiltiy to barotrauama..pro-inflam or diabetes Decreased neprhon mass

Question 26

Pathh of HTN neprho

Answer 26

INcreased systemic pressure Affarent constriction to dec intragolmerular pressure...efferent arteriole dilates

Question 27

Hyaline arterioloscelrosis

Answer 27

Medial and intimal thickening Mostly of the affarnet Haline deposition caused by extravasation of proteins throgu hendothelium and partly by increase BM deposition

Question 28

HYlainization of glmeruli

Answer 28

Narrowing of lumen of AA leads to dec blood flow and results in ischemia and glomerular damge Hyalinization of glomerulus and loss of glomerular function

Question 29

Tubular hyalizniation

Answer 29

Dec blood flow to the tubules and interstitium leads to cell death and loss of nephron function Progressive loss of neprhons

Question 30

Bad synergy with DM

Answer 30

Diabetic nephropathy increase in the RAA via AT2 leads to efferent arterial constriction further increased the glomerular HTN and accelerating the damage

Question 31

Hx of patients with HTN nephro

Answer 31

HTN for a long time with evidence of uncontrolled BP More comps than you think they should have

Question 32

Features usggesting HTN neprho

Answer 32

Proteinuria is a big one Black HTN dx prior to proteinuria LEft ventricular hypertrophy

Question 33

HTN neprho tx

Answer 33

ACE inhibitors but diuretic needs ot be co-admin

Question 34

HTN emergency

Answer 34

Severe HTN (diastolic above 120) with rapid decomp of organ system OR life-therating conditions aggravated by presence of elevated BP Lower over minutes ot horus

Question 35

HTN emergency clinical cues

Answer 35

Moderate to severe HTN retinopathy (malignant HTN)

Question 36

Severe asx HTN

Answer 36

Relatively asx or completely asx patient iwth a BP in the severe range...maybe a mild headache Does NOT require rapid reduciton of BP Rapid reduciton of BP may be harmful BP reduced over a period of days

Question 37

HTN emergencies clinical

Answer 37

Reflects consequens of BP on tagret organs Depends on level and rate of BP Affected by pre-existing HTN

Question 38

CLinical pres of malignant HTN

Answer 38

``` HA - worse in morning Visual Ischemic CP Renal N//V Neurologic ``` Depends on involved organ system

Question 39

Etiology of malignant

Answer 39

Essential HTN most common with renal parenchymal as seocndary

Question 40

Pathophys of malignant

Answer 40

Crticial evaluiatioj of BP Loss of autoregulation Vascular endothelai damage - loss of permeability with deposition of fibrinogen and plasma proteins in walls...activation of mediators of coagulatio nand cell proliferation Localized intravasc activation of clotting cascade - microangiopathic hemolytic anemia Act of RAAS Natriuresis from pressure POsitive ffedback to increase more

Question 41

Patho of Malig HTN

Answer 41

Proliferative endarteritis (onion skin) Fibrinoid necrosis Kidney - fibrinoid neprho of glomeruli, heorrhage and fibrosis of intersittium, tublar artophy or ATN

Question 42

Microangiopathic hemolytic anemia

Answer 42

RBCs traverse an injured vascular endothelilum with associated fibrin depositon and platelet aggrgeation Fragmentation hemolysis Mech disruption of RBC membrane IV hemolysis and appearance of schistocytes

Question 43

Malignant HTN therpay

Answer 43

ICU Arterial line Rapid reduciton of MAP by 20% 160-170/100-110 SHort acting IV agents

Question 44

Malig HTN prognosis

Answer 44

75% survive 5 years and 50% survive with restoration of pre-crisis renal function