10 Kidney stones

Question 0

Nephrocalcinosis

Answer 0

Depositis in tubules and interstitial space, not pelvis or calyx

Question 1

Medullary Sponge Kidney

Answer 1

Dilated and calcified medullary pyramids

Question 2

Stone forming process

Answer 2

• Crystals usually form in tubule
• crystals aggregate
• are encased in protein
• Subepithelial calciumphosphate depostis (assocaited with stone disease) (perhaps erode through and release crystals?) (cause ddamage to make walls sticky for crystals?)

Question 3

Kidney stone composition

Answer 3

• Calcium oxalate 75%
• calcium phosphate 30%
• Uratess
• Struvite - infectous
• Cysteine

Question 4

SEM of stones

Answer 4

Aggregates of small crystals- formed in layers

Question 5

Epidemiology

Answer 5

5-15% usa
Men>women (2/5-1
White more commonly affected
50% recurrence in 5 yrs
Common in "dixie states"

Question 6

Drugs that promote stone formation

Answer 6

Indinavir
Acyclovir
Triamterene
Sulfamethoxazole

Ethelenee glycol

Question 7

Genetic causes

Answer 7

Cysteinura
Hyperoxalosis- Calcium oxalate crystals
Dent Disease- Calcium oxalate or calcium phosphate
Familial hypomagnesemia with hypercalcemia with neohrocalcinosis- Calcium (Phosphate?)
APRT deficiency- 2,8, dihydroxy adenine
Distal renal tubular acidosis- CaPO4

Question 8

L cysteine stone Disease

Answer 8

Non- reabsorbed Cysttein precipitates at urine pH

• Type A38%- Recessive SLC3A1 targeting for receptor defective
• Type B 47%- incomplete dominance Cysteine transporter defective

Question 9

Primary Hyperoxalosis

Answer 9

Very rare

• PH1 80% Alanine-glyoxylate aminotransferrase deficiency
  
  • OXALATE and GLYCOLATE
• PH2 10% Glycolate/hydroxylpyruvate reductase (GRHPR) defecit
  
  • GLYCERATE and OxALATE
• PH3 10% 4-OH2oxaloglutarate aldolase (HOGA1) deficiency
  
  • OXALATE only

Question 10

Calcium oxalate shapes

Answer 10

monohydrate- circular crrystals

Dihydrate- dipyramidal

Question 11

Oxalate stone disease

Answer 11

• Hyperalkylosis - stones throughout body
• Enteric and Ileojejunal bypass patients- malabsorption causes high oxalate extraction from foods
• Hereditary

Question 12

Stone risk factors

Answer 12

Main
*History, polycystic kidney disease, renal tubular acidosis, medullary sponge disease, transplant and ESRD
Others
*ibd, short gut, hyperparathyroidism, hypercalcemia, gout, HIV
Diet
* Low fluid intake, high salt, high protien/meat, low calcium intake, high oxalate- spinache beets rhubarb, nuts, beans, chocolate, soy beans, tea

Question 13

Stone analysis

Answer 13

Serum labs:
* Chem panel, calcium, Albumin, Phosphorus, MG, uric acid, PTH, VitD
UA:
*Creatnine, crystals (Ca,Ox, phosphates, uric acid, cysteine), Volume, pH, Na, Cittrate, Mg, K

Question 14

Crystal shapes

Answer 14

CaOx mono- ovoid di-bipyramidal
Struvite-Coffin lid(triangular prism)
Cysteine(hexagonal)
Uric acid (football)

Used only to diagnose type- persance of small crystals in urine doesnt suggest crystal disease.

Question 15

Kidney stone treatment

Answer 15

*Medical
Symptom managemennt, alpha blockers, steroids, Ca blockers- relax ureters, Uric acid dissolution of urate stones
*Extracorporeal shock wave lithotrypsy
*uretoscopy- stone basketing/ laser or electrohydraulic lithotrypsy
*Percutaneous surgery

Question 16

Cysteine stone disease treatment

Answer 16

Dilution- drink more
Alkalinize urine
Cysteine binding drugs
   -Penicillamine Lots of SE
   -Tiopronin Lots of SE
   -Catopril- ACEi (causes hypotension at effective doses)

Question 17

UA crystal treatment

Answer 17

Dilution
Low protein diet
Alkilinization of urine
XO inhibitors
  -allopurinol
  -febuxstat

Question 18

Struvite treatment

Answer 18

• Dilution
• antibiotics
• surgical residual stone removal
• Ureasee inhibitors and chemolysis

Question 19

Ca stone tratment

Answer 19

Dilution
Normal Ca intake diet
low protein NA diet to prevent Ca excretion
Thiazide diuretic
reduce oxalate in diet
Increase urine citrate
-high fruit low potein
-citrate or bicarb supplements