1. DEPARTMENT OF UROLOGY IAŞI – 2013
URINARY STONE DISEASE
DEPARTMENT OF UROLOGY IAŞI – 2013

2. INTRODUCTION
3rd most common condition of the urinary tract (1 – UTIs, 2 – prostate diseases)
stone recurrence rates – 50% within 5 years !

3. RENAL & URETERAL ETIOLOGY
composition = crystals + organic matrix (2-10%)
supersaturated urine  stone formation
urinary pH
ionic strength (concentration of monovalent ions)
solute concentration (concentration of 2 ions, solubility product, formation product)
complexation (Na – oxalate, sulfate – Ca)
inhibitors (magnesium, citrate, pyrophosphate, trace metals)
nucleation theory – crystals or foreign bodies immersed in supersaturated urine
crystal inhibitor theory – absence or low concentration of natural stone inhibitors

4. RENAL & URETERAL
nucleation (heterogeneous – epitaxy !), growth & aggregation  stone formation
retention in the upper urinary tract (nephrocalcinosis !)
mass precipitation theory (intranephronic calculosis)
fixed particle theory – Randall plaques, Carr corpuscles
matrix calculi – previous kidney surgery & chronic UTIs
STONE VARIETIES
Calcium Calculi (80-85%)
absorptive hypercalciuria –  Ca absorption   Ca filtered (glomerulus)   PTH   tubular reabsorption of Ca   Ca ur
resorptive hypercalciuria – primary hyperparathyroidism (parathyroid adenoma)   P ur,  P sr   Ca sr,  Ca ur  renal damage   Ca ur

5. RENAL & URETERAL
renal hypercalciuria – intrinsic renal tubular defect in calcium excretion   Ca ur   Ca sr   PTH (secondary)   Ca resorbtion (bone) & absorption (gut)   Ca ur
hyperuricosuria
hyperoxaluria – primary or enteric (inflammatory bowel disease)
hypocitraturia – metabolic acidosis, hypokalemia (thiazide therapy), fasting, hypomagnesemia, androgens, UTI
Noncalcium Calculi
struvite – magnesium, ammonium and phosphate
uric acid
cystine – autosomal recessive
xanthine, indinavir, silicate, triamterene

6. RENAL & URETERAL SYMPTOMS & SIGNS AT PRESENTATION Pain renal colic
noncolicky renal pain
Hematuria
Infection – pyonephrosis, xanthogranulomatous pyelonephritis
Fever, Anuria !, Nausea and Vomiting
EVALUATION
Risk Factors – crystalluria, socioeconomic factors, diet, occupation, climate, family history, medications
Physical Examination
Imaging Investigations – US, KUB film, IVU, CT (noncontrast spiral), retrograde pyelography, nuclear scintigraphy

7. RENAL & URETERAL
Differential Diagnosis – acute appendicitis, ectopic pregnancies, twisted ovarian cysts, diverticular disease, bowel obstruction, biliary stones, peptic ulcer disease, acute renal artery embolism, abdominal aortic aneurysm etc.
INTERVENTION
Conservative Observation – spontaneous passage!
Dissolution Agents – oral alkalinizing agents (sodium or potassium bicarbonate and potassium citrate), i.v. alkalinization (sodium lactate), intrarenal alkalinization (sodium bicarbonate) – acidification – hemiacidrin (Renacidin)
Relief of Obstruction – JJ ureteral stent, PNS

8. RENAL & URETERAL ESWL (Extracorporeal Shock Wave Lithotripsy)
electrohydraulic, piezoceramic, electromagnetic
approximately 75% of patients with renal calculi (< cm) treated with ESWL become stone-free in 3 months

9. RENAL & URETERAL Ureteroscopic Stone Extraction
highly efficacious for lower ureteral calculi
stone-free rates range from %
lithotrites – electrohydraulic, ultrasonic, laser, pneumatic

10. RENAL & URETERAL Percutaneous Nephrolithotomy
choice for large (> 2 cm) calculi, those resistant to ESWL, select lower pole calyceal stones and instances with evidence of obstruction
Remaining calculi can be retrieved with flexible endoscopes, additional percutaneous puncture access, follow-up irrigations, ESWL, or additional percutaneous sessions

11. RENAL & URETERAL Open Stone Surgery pyelolithotomy
anatrophic nephrolithotomy
radial nephrotomy
nephrectomy
ureterolithotomy

12. BLADDER
manifestation of an underlying pathologic condition, including voiding dysfunction (urethral stricture, BPH, bladder neck contracture, neurogenic bladder) or a foreign body
irritative voiding symptoms, intermittent urinary stream, urinary tract infections, hematuria, or pelvic pain US
electrohydraulic, ultrasonic, laser, pneumatic and mechanical lithotrites
cystolithotomy