Kidney Stones Medical Management

Question 1

Initial work up for patient with newly diagnosed stones

Answer 1

-Medical history (Obesity, hyperthyroidism, gout, RTA type 1, DM2, hyperparathyroidism, malabsorptive GI states)
-Dietary history (calcium intake, fluid intake, meat intake, oxalate foods)
-Medications (probenecid, protease inhibitors, triamterene, chemo, topamax, zonisamide)
-Serum chemistries (CMP, calcium
-UA with micro
-Quantify stone burden
-Further metabolic workup for recurrent stone formers or high risk/interested first time stone formers

Question 2

When should PTH be checked?

Answer 2

High or high-normal Ca
CaPhos stone
High urinary calcium
Also check Vitamin D

Question 3

Metabolic testing components

Answer 3

24hr urine (1-2x)

Question 4

When should testing be done for primary hyperoxaluria?

Answer 4

> 75mg/day in adults without bowel dysfunction

Question 5

Recommend urine volume for stone formers

Answer 5

2.5L/day

Question 6

Counseling re: calcium intake and calcium stones

Answer 6

1000-1200mg a day

Question 7

Recommendations for calcium oxalate stones

Answer 7

2.5L urine per day
Limit calcium to 1000-1200mg
Limite oxalate rich foods (potatoes, spinach, nuts, soy, pumpkin, chocolate, processed meats, beans)
DASH diet
Increase fruits/vegetables and citrate intake
Decrease protein intake if uric acid high
thiazide if urine calcium high (add K too)or empirically
Kcit if low urinary citrate or empirically
Allopurinol if recurrent CaOx and high urinary uric acid and normal urinary calcium

Question 8

Recommendations for cystine stones

Answer 8

4L intake per day
Limit sodium to 2300mg or less daily
Limit animal protein intake
Alkalinize urine with kcit
Tiopronin (2nd line)

Question 9

Treatment for stone former with low pH and uric acid or cystine stones

Answer 9

Kcit

Question 10

Should allopurinol be used for uric acid stone formers?

Answer 10

not routinely

Question 11

Recommendations for struvite stones

Answer 11

Clear stone burden
Treat infection
Consider AHA - watch for phlebitis and hypercoag

Question 12

When should 24hr urine be repeated after starting a drug for stones?

Answer 12

within 6 months and annually thereafter

Question 13

What type of stones form with urease splitters?

Answer 13

struvite

Question 14

what bacteria produce urease

Answer 14

proteus, providencia, klebsiella, pseudomonas

Question 15

Side effects of SWL

Answer 15

Hematoma
Hemorrhage
Residual stones
HTN
Sepsis
Obstruction

Question 16

ESWL procedure

Answer 16

Localize stone
Go slow (60hz)
Pause

Question 17

Management of ureteral avulsion

Answer 17

Stent (if possible)
NT and staged repair
U-U (if high)
Reimplant (if distal) +/- Psoas hitch/Boari
Ileal ureter
Autotransplant
Nephrectomy
do NOT do transUU if unilateral stone former

Question 18

Indications for intervention for a patient on MET

Answer 18

Persistent poorly controlled pain
Intractible N/v
Fever, leukocytosis
Worsening AKI
Failure to progress
Patient preference

Question 19

hypercalciuria definition

Answer 19

> 200mg in 24hr urine specimen

Question 20

Causes of hypercalcemia

Answer 20

HyperPTH
Sarcoid
Hyperthyroid
MM
Paget’s
Milk Alkali
VitD intoxication

Question 21

Types of hyperoxaliuria

Answer 21

Primary - congenital - can cause renal failure - treatment is liver transplant
Acquired - usually enteric deficit (IBD, GI bypass, short gut)

Question 22

Lasix scan interpretation

Answer 22

<12 min non-obstructed
12-20 mins equivocal
>20 min obstructed