Urinary Lithiasis Flashcards Preview

Nelson: Urologic Disorders > Urinary Lithiasis > Flashcards

Flashcards in Urinary Lithiasis Deck (26):
1

Approx 75% of all stones contain ___ as major constituent and 60% are composed of ___

Calcium; calcium oxalate

2

Stone formation depends on 4 factors

1) Matrix 2) Precipitation-crystallization 3) Epitaxy 4) Absence of inhibitors of stone formation

3

Refers to supersaturation of the urine with specific ions composing the crystal

Precipitation-crystallization

4

Refers to the aggregation of crystals of different composition but similar lattice structure

Epitaxy

5

If the calculus is present in these areas, then severe abdominal or flank pain (renal colic) occurs

Pelvis, calyx, ureter

6

Renal colic typically radiates where

Anteriorly to the scrotum or labia

7

Nephrocalcinosis is seen most commonly in premature neonates receiving ___ and in children with ___

Furosemide, medullary sponge kidney

8

Most accurate study to diagnose urolithiasis

Unenhanced spiral CT of the abbdomen and pelvis

9

T/F Metabolic evaluation should be undertaken in ALL children with urolithiasis

T

10

MC metabolic abbnormality in children with CaOx and CaPhos calculi

Normocalcemic hypercalciuria

11

Increases solubility product of calcium oxalate crystallization 7-10x more than calcium

Oxalate

12

Death from renal failure occurs in untreated patients with hyperoxaluria by age ___

20

13

Extrarenal deposition of CaOx

Oxalosis

14

Renal insufficiency + elevated plasma oxalate

Oxalosis

15

Risk factor for formation of CaOx and CaPhos stones due to low excretion of an important inhibitor of calcium stone formation

Hypocitraturia

16

Rare autosomal recessive disorder of the EC of the renal tubules that prevents absorption of 4 dibasic amino acids resulting in excessive urinary excretion of these products

Cystinuria

17

4 dibasic amino acids unabsorbed in cystinuew

Cysteine, ornithine, arginine, lysine

18

Calculi resulting from UTI caused by urea-splitting organisms

Struvite calculi

19

Urea-splitting organisms, infection of which causes formation of struvite calculi

Most often Proteus, occasionally Kleb, E.coli, Pseudomonas

20

Presence of urea-splitting organisms in the urine causes

Urinary alkalinization and excessive production of ammonia --> precipitation of magnesium ammonium phosphate (struvite) and calcium phosphate

21

Staghorn calculi

Struvite calculi

22

Shown to facilitate stone passage in adults by decreasing ureteral pressure below stone and decreasing frequency of peristaltic contraction of the obstructed ureter

α-adrenergic blockers (tamsulosin, terazosin, doxazosin

23

Alkaline therapy may be effective in dissolution of what type of stones

Uric acid, furosemide-associated calculus, cysteine calculi

24

Effective management strategies for children with hypercalciuria to prevent stone formation

1) Reduction in calcium and sodium intake 2) Thiazide diuretics (reduces renal Ca excretion) 3) K citrate (calcium stone inhibitor)

25

Effective management strategies for children with uric acid stones

1) Allopurinol 2) Urinary alkalinization >6.5 with NaHCO3 or Na citrate

26

Effective management strategies for children with cysteine stones

1) Urinary alkalinization 2) D-penicillamine (increases solubility of cysteine)