Chronic Kidney Disease - Huch

Question 1

What is the definition of chronic kidney disease?

Answer 1

best index of overall kidney function is glomerular filtration rate, typically estimated by measurement of creatinine clearance and by changes in serum creatinine concentration

Question 2

What is the difference in urine analysis in chronic kidney disease when the disease is in the glomerulus vs the tubules?

Answer 2

in the glomerulus - has more protein

in the tubule - no heavy protein count, maybe pyuria

Question 3

What are some factors that suggest chronic kidney disease>

Answer 3

most common asymptomatic until really bad
presence of peripheral neuropathy
bone changes consistent why hyperparthyroidism
small kidneys
waxy casts (cracks, sharp edges)

Question 4

What are factors suggesting a tubular etiology of chronic kidney injury

Answer 4

absence of heavy proteinuria
inability to concentrate or dilute urine so that specific gravity is typically 1.010 isoosmotic to plasma
presence of hyperkalemia and metabolic acidosis out of proportino to the degree of renal insufficiency

Question 5

What are factors that suggest glomerular etiology in chronic kidney disease?

Answer 5

2+ proteinuria
presence of rbc casts
specific gravity great than 1.015

Question 6

what is the most common cause of eosinophils in the urine

Answer 6

allergic interstitial nephritis

Question 7

what are features of allergic interstitial nephritis?

Answer 7

eosinophils in urine

pyuria

Question 8

When initial injuring stimulus is removed in chronic kidney disease, describe the progress of the kidney function

Answer 8

chronic kidney disease will continue to worsen when the injuring stimulus is removed

Question 9

What are common signs of advanced renal failure? commonly called uremia

Answer 9

early morning nausea
increased edema
hiccup
itching

Question 10

Uremia is 100% fatal unless?

Answer 10

reversible factors are identified which can improve GFR

renal replacement therapy is instituted

Question 11

What are teh most common etiologies of advanced kidney disease in the US?

Answer 11

diabetes mellitus
htn nephrosclerosis
acute and chronic glomerular disease
polycystic kidney disease
tubulointerstitial disease

Question 12

what are disease dependent mechanisms of nephron injury

Answer 12

vascular, glomerular, tubular

Question 13

what are disease independent mechanisms of nephron injury

Answer 13

systemic htn
glomerular htn
glomerular hypertrophy (increase sngfr per nephron) - compensating for dying nephron

Question 14

how does the kidney and nephrons respond to nephron loss?

Answer 14

compensatory glomerular hypertoprhy

compensatory glomerular hyperfiltration

Question 15

a 50% decrease in renal mass results in only 20-30% reduction in GFr. Therefore, residual nephrons increased sngfr about 50%. t of f

Answer 15

ture

Question 16

What are effects of disease indpt processes like hypertrophy?

Answer 16

epithelial cell injury promoting proteinuria
hyaline accumulation in mesangial expansion leading to reduced capillary surface area for gfr
vascular capillary microaneurysms
endothelial cell injury
tubulointerstitial fibrosis

Question 17

Greater than 50% loss of nephron mass results in increased risk of what?

Answer 17

htn
proteinuria (focal segmental glomerulosclerosis)
particularly when present for more than 10 yrs

Question 18

in cases of progressive nephron loss, why is protein restriction dangerous?

Answer 18

while it is tremendously helpful in reducing azotemia and reducing the workload of the glomeruli, it also leads to malnutrition

Question 19

in proteinuria disease, what drugs have been shown to give extra advantage for bp regulation

Answer 19

acei and arbs

Question 20

why would acei and arbs be particularly helpful in proteinuric diseases?

Answer 20

they stop the raas, which leads to efferent vasoconstriction, contributing to systemic htn, they lead to na retention, glomerular htn, and increased release of tgf-beta, promoting fibrosis

Question 21

what are limitatinos of serum creatinine as a marker for gfr?

Answer 21

increased secretion occurs with decreased gfr, therefore, the serum creatinine will over-estimate true gfr

Question 22

what are early changes in diabetic nephropathy?

Answer 22

hyperfiltration resulting in glomerular capillary hypertension and glom hypertrophy. have a gfr increase from 100 to 130

Question 23

What are the clinical effects of diabetic nephropathy?

Answer 23

first abnormality is microalbuminuria that leads to overt proteinuria, reduced gfr and htn

Question 24

what are histologic effects of diabetic nephropathy?

Answer 24

increased, mesagnial matrix, glomerular collapse and glomerulosclerosis

Question 25

does inhibition of raas reduce plasma creatinine?

Answer 25

yes, because it tries to make sure the gfr is staying normal

Question 26

What do most people die of before they ever get to dialysis?

Answer 26

cv events

Question 27

do damaged nephrons function normally or abnormally?

Answer 27

normally, so loss of renal homeostasis is due to decreased number of nephrons.

Question 28

what is the trade off hypothesis?

Answer 28

in order to maintain homeostasis despite reduced GFR, things happen to make sure homestasis occurs.

ca.po4 hyperparathyroidism
na balance htn
k hyperaldosteronism and htn
increased filtration by residual nephrons

Question 29

why do you estimate gfr instead of using Scr?

Answer 29

because muscle mass determines cr, so there is no normal value for creatinine, only normal for the context

Question 30

what is the equation for GFR estimation?

Answer 30

140-age/Scr X .85 (if fem)

Question 31

until what gfr is the kidney able to maintain K intake?

Answer 31

gfr less than 15 ml per min. the is important since severe hyperkalemia is most life-threatening electrolye abnormality