Upper Urinary Tract Obstruction Facts

Question 1

severity of a urinary tract obstruction is determined by

Answer 1

the location of the obstructive lesion
the involvement of ureters and kidneys
the severity (completeness) of the blockage
the duration of the blockage
the nature ofthe obstructive lesion

Question 2

common causes of upper urinary tract obstructions are

Answer 2

kidney stones (calculi)

Question 3

upper urinary tract obstructions result in

Answer 3

dilation of ureter (hydroureter)
dilation fo the renal pevis and clyces proximal to the blockage (hydronephrosis or ureterhydronephrosis which is both)
decreases glomerular filtration rate (GFR) (hydrostatic pressure from backup opposes hydrostatic pressure of glomerular filteration)
acute kidney injury from delayed fixing of blockage (7 to 28 days)

Question 4

the prevalence of kidney stones in the US is approximately ______ individuals over a lifetime

Answer 4

1 in 11

Question 5

the recurrence rate of kidney stones is approximately

Answer 5

30% to 50% within 5 years

Question 6

most people develop their first kidney stone by age _____

Answer 6

50 (highest rate is in caucasians)

Question 7

what percentage of men and women get kidney stones

Answer 7

7% of women 10% of men

Question 8

risk of kidney stone increased with

Answer 8

sedentary occupation
genetics
geographic location

Question 9

types of kidney stones and how common they are

Answer 9

calcium oxalate or phosphate (70-80%)
struvite (magnesium-ammonium-phosphate) (15%) “infection stones”
uric acid (7%)
cystine or xanthine (<1%)

Question 10

reasons for kidney stone formation

Answer 10

supersaturation of one or more salts in the urine
precipitation of the salts from a liquid to a solid state
growth through crystallization or agglomeration
presence or absence of stone inhibitors (uromodulin, also called Tamm-Horsfall protein)
based on urine pH (alkaline - calcium phosphate and struvite, acidic - uric acid and cystine and xanthine)

Question 11

size of kidney stones and how likely you are to pass them naturally (through urinary tract)

Answer 11

5mm, 50% chance
1cm, almost no chance

Question 12

risk factors for kidney stones

Answer 12

immobilization increases risk
diet
* low sodium reduce Ca stones
* high sodium increase Ca stones
* limiting Ca in diet usually not helpful
* dietary Ca supplements may increase risk
* lack of water intake
* oxalate stones diet risks
1. peanuts, tea, instant coffee (>8oz/day), rhubarb, beets, beans, berries, chocolate, concord grapes, dark leafy greens, oranges, tofu, sweet potato, draft beer

Question 13

symptoms of kidney stone

Answer 13

renal colic
* flank pain
* costovertebral angle
* radiates to groin
* can be severe pain
hematuria (blood in urine) (gross or microscopic)
oliguria (low urine output)

Question 14

treatment for kidney stone

Answer 14

pain management
lithotripsy (fragment stone for excretion in urine)
nephrolithotomy
reduce concentration of stone forming substances by increasing fluid intake
adjusting pH of urine or dietary intake