Nephrolithiasis

Question 1

what is nephrolithiasis?

Answer 1

• kidney stones also called renal calculi
• stones develop in kidney can migrate out to anywhere in urinary tract
• stones in urinary tract (renal calculi)

Question 2

who is more likely to get kidney stones?

Answer 2

-more likely in males (2-3X higher incidence in men)

Question 3

where does nephrolithiasis originate?

Answer 3

-originates in the kidney (could have in both kidneys but generally in 1) then migrates then may cause obstruction

Question 4

nephrolithiasis (kidney stones) the most common cause of?

Answer 4

nephrolithiasis (kidney stones) is the most common cause of obstruction in the urinary tract

Question 5

what is the etiology of kidney stones?

Answer 5

• complex interaction:
  - increase in concentration of precipitate components in blood & urine
  - structural changes in urinary tract
  - fluid, dietary & metabolic factors (what you eat is what you absorb is what you metabolize)

Question 6

there are some things that prevent us from forming stones all the time, what are these?

Answer 6

• renal proteins inhibit crystallization

- presence of stone inhibitors eg. magnesium & citrate (prevent stones from forming)

Question 7

what is the nidus or nucleus?

Answer 7

the first particle that begins to form stone

Question 8

what is the patho of kidney stones

Answer 8

• increase in solute concentration & or urine stasis
• precipitation in urine
• nucleus (also called nidus) forms around which other components will accumulate
• crystallization

Question 9

there are _____ types of kidney stones

Answer 9

4

Question 10

what are the 4 types of kidney stones?

Answer 10

• calcium (oxolate & phosphate)
• magnesium ammonium phosphate (strurite)
• uric acid (urate)
• cystine

Question 11

calcium (oxolate & phosphate ) stones

Answer 11

Contributing factors:

• hypercalcemia & hypercalciuria
• immobilization
• hyperparathyroidism
• vitamin D intoxication
• diffuse bone disease
• Milk-alkali syndromes
• renal tubular acidosis
• hyperoxaluria
• intestinal bypass surgery

Treatment:

• treatment of underlying conditions
• increased fluid intake
• thiazide diuretics
• dietary restriction of foods high in oxalate

Question 12

mnfts of nephrolithiasis (kidney stones)

Answer 12

• very severe colicky pain (minutes to days): intermittent because hurts as stone moves, ureter or urethra distention d/t migration of stone
• non colicky pain (distention of renal pelvis & calyces stone not attempting to pass
• N&V from severe pain

Question 13

Magnesium ammonium phosphate (strurite) stones

Answer 13

Contributing factors:
-urea-splitting urinary tract infections

Treatment:

• treatment of urinary tract infection
• acidification of urine
• increased fluid intake

Question 14

uric acid (urate) stones

Answer 14

Contributing factors:

• formed in acid urine with pH of approx 5.5
• gout
• high purine diet

Treatment:

• increased fluid intake
• allopurinol for hyperuricosuria
• alkalinization of urine

Question 15

cystine stones

Answer 15

Contributing factors:
-cystinuria (inherited disorder of amino acid metabolism)

Treatment:

• increased fluid intake
• alkalinzation of urine

Question 16

diagnosing nephrolithiasis (kidney stones)

Answer 16

• the pattern of the pain (dont rely on this)
• CT, ultrasound (to identify stone)
• urinalysis (looking for signs of complications: infection, hematuria, proteinuria)
• IVP (intravenous pyelogram) DONE REGULARLY IN THE PAST SO IT IS V. IMPORTANT THAT I KNOW THIS (administer contrast medium intravenously, goes through blood path visualize path through urethra & glomerulus)

Question 17

treatment of nephrolithiasis (kidney stones)

Answer 17

• supportive treatment
• small stones passed in urine (when passed collected, analyzed, see if can address diet to prevent)
• narcotics & antispasmodics (ex. Buscopan)
• underlying cause? (ex. BPH, obstruction)
• Surgery may be required (also can blast stones with high frequency sound waves)