Kidney Stones Flashcards
dietary interventions to prevent calcium stone reoccurrence
reduce Na, reduce animal protein, increase Ca intake, increase daily fluid intake, increase citrate, increase fruits and vegetables.
How does increased Ca intake help decrease Ca oxalate stones?
decreases oxalate absorption in GI tract if there’s more Ca ingested and it prevents urinary excretion of oxalic acid.
How does fluid decrease Ca oxalate stones?
increased urinary flow and decreased solute conc
How does increasing citrate decrease Ca oxalate stone?
decreases urinary Ca (binds to urinary Ca to inhibit stone formation)
How does increased fruits and veggies decrease Ca oxalate stone?
Increased citrate excretion in kidney
Is supplementary Ca increase or decrease risk for Ca oxalate stone?
increases.
Ok to increase dietary Ca to help reduce but supplementary can increase risk for stones.
What does high sodium intake do to risk for Ca oxalate stones?
high Na intake decreases Proximal tubule Na reabsorption so increases urinary Ca levels and increased risk for stone development.
What does coffee, alcohol and tea do for your risk of Ca oxalate stones?
helps decrease risk due to diuretic effect.
when a kidney stone need to first rule out what?
urosepsis, acute renal failure, complete obstruction
if stone is >10 mm
urology consult
If stone is <10 mm
hydration, pain control alpha blockers (tamsulosin) and strain urine to categorize
If stone is <10 mm at what point do you consult urology?
uncontrolled pain, no stone passage in 4-6 weeks.
treatment of stones >10 mm
shock wave lithotripsy or ureteroscopy but with big stones >15 mm need endoscopic stone fragmentation.
When do we put in percutaneous nephrostomy tube?
if hydronephrosis or signs of rapidly progressive renal failure
what causes cysteine kidney stones?
rare and seen with cysteinuria a genetic defect classified by urinary cysteine (often >400 mg/day)
Have hexagonal cysteine cyrstals
are cystine stones seen on CT scan?
can see on CT scan but less radiopaque compared to calcium nephroliths.
what shape of kidney stone do cysteine kidney stones have?
hexagonal
how to treat cysteine stones?
increase fluid intake to 2L and restrict intake of protein and sodium and alkalizing urine to increase cysteine solubility with potassium bicarbonate or potassium citrate will help keep ph>7.
how to treat uric acid nephrolithiasis?
xanthine oxidase inhibitors like allopurinol.
how does citrate help decrease formation of calcium stone?
it binds to calcium and decreases calcium stone formation. Dietary sources of citrate are 4 oz of lemon juice and increase urinary citrate excretion.
how does increasing fruit and vegetable intake and decreasing animal protein help decrease calcium stone formation
fruits and veggies increase citrate excretion in kidney
decreasing animal protein helps to decrease acid load and urinary calcium excretion