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Flashcards in Chronic Kidney Disease - Huch Deck (31)

What is the definition of chronic kidney disease?

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


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

in the glomerulus - has more protein

in the tubule - no heavy protein count, maybe pyuria


What are some factors that suggest chronic kidney disease>

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


What are factors suggesting a tubular etiology of chronic kidney injury

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


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

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


what is the most common cause of eosinophils in the urine

allergic interstitial nephritis


what are features of allergic interstitial nephritis?

eosinophils in urine


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

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


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

early morning nausea
increased edema


Uremia is 100% fatal unless?

reversible factors are identified which can improve GFR

renal replacement therapy is instituted


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

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


what are disease dependent mechanisms of nephron injury

vascular, glomerular, tubular


what are disease independent mechanisms of nephron injury

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


how does the kidney and nephrons respond to nephron loss?

compensatory glomerular hypertoprhy
compensatory glomerular hyperfiltration


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



What are effects of disease indpt processes like hypertrophy?

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


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

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


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

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


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

acei and arbs


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

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


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

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


what are early changes in diabetic nephropathy?

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


What are the clinical effects of diabetic nephropathy?

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


what are histologic effects of diabetic nephropathy?

increased, mesagnial matrix, glomerular collapse and glomerulosclerosis


does inhibition of raas reduce plasma creatinine?

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


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

cv events


do damaged nephrons function normally or abnormally?

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


what is the trade off hypothesis?

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


why do you estimate gfr instead of using Scr?

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


what is the equation for GFR estimation?

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


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

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