2. 2
Urinary stones have afflicted humankind since
antiquity with the earliest recorded example
being bladder and kidney stones detected in
Egyptian mummies dated to 4800 BC.
The specialty of urologic surgery was
recognized even by Hippocrates, who wrote, in
his famous oath for the physician, “I will not cut,
even for the stone, but leave such procedure to
the practitioner of the craft”
The recurrence rate without treatment for
calcium oxalate renal stones is about 10% at 1
year, 35% at 5 years, and 50% at 10 years.
3. 3
Age & Sex
Incidence
20 – 40 years
Male Female
3 1
Testosterone UTI
↑ Endogenous production
of oxalate by liver
Hyperparathyroidism
Cystinuria
4. 4
PHYSICAL CHEMISTRY
Phenomena
Nucleation will occur
Inhibitors not generally effective
Crystal growth will occur
Crystal aggregation will occur
Inhibitors will impede or prevent crystallization
De novo nucleation is very slow
Hetrogeneous nucleation may occur
Matrix may be involved
Crystals will for form
Existing stones may dissolve
Formation
Product
Solubility
Product
Concentration
Product
State of Saturation
5. 5
RENAL STONES
Second commonest site of stone formation in
the body.
Prevalence 2 to 3 percent.
5 % lifetime risk of developing renal stones.
Accounts for 10 to 15% of CRF patients. (1 t0 2
% in western countries)
8. 8
AETIOLOGY
(Environmental Factors)
Hot Climate
Warm desert region
Mountains & Tropical Areas
Water Intake
Areas having Chronic / Endemic Diarrhea leading to dehydration
?? Hard Water
Zinc in consumed Water
Diet
Excessive Intake of Calcium
Excessive Intake of Oxalates
Excessive Intake of meat/meat products (purines)
9. 9
AETIOLOGY
(Factors in the Urinary Tract)
Obstruction
Horse-shoe Kidney
PUJ Obstruction
Medullary Sponge Kidney
Subtle anatomic Abnormality in the kidney not visible to the
naked eye
Infection
Urease Splitting Organisms
Nidus for Stone Formation
Randal Plaque
12. 12
Inhibiters of Stone Formation
Citrates
Mg
Tamm - Horsefall Proteins
Nephrocalcin
Glycoprotein
Orthophosphates / Cellulose Phosphate
13. 13
Types of Renal Stones
Calcium Oxalate
75 % to 80 % of renal stones
Irregular / Spiky Surface
Can be single or multiple
Hyper Oxaluria & Acidic urine predisposing factors
Exists as monohydrate / dihydrate
Radiopaque on Radiography
Calcium Phosphate & Triple Phosphate
15 % o 20 % of renal stones
Struvite stones
Require alkaline urine, so formed in infection with urease splitting
organisms & RTA
Can attain very large size & account for the majority of staghorn calculi
Usually single but may be multiple
Relatively fragile stone and amenable to lithotripsy
Radiopaque on Radiography
14. 14
Types of Renal Stones
Uric Acid Stones
Account for 5 % to 10 % of renal stones
Typically radiolucent
Usually have smooth surface
Can be single or multiple
Formed in acidic urine
Cysteine Stones
Account for 1 % to 2 % of renal stones
Formed in hypercystineuria which is an autosomal recessive disorder
Faintly radiopaque
Usually single
Amenable to medical treatment
Formed in acidic urine
Rare Stones
Xanthine
Di-hydroxy adenine
Triamterine
25. 25
Investigations
To detect the presence of stone
C.t scan / spiral (Helical) c.t Scan
To detect the cause of the stone formation
Serum calcium
Serum uric acid
Serum oxalate
Serum phosphate
Pth level
24 hrs excretion of calcium, phosphate, urate, oxalate &
citrates
26. 26
Medical Treatment
General measure of prevention
Hydration
Diet
Dietary protein
Dietary calcium
Dietary sodium
Dietary oxalate
Dietary phosphate
Dietary fiber
Special Measures
Thiazides
Orthophosphates
Sodium cellulose phosphate
Allopurinol
Citrates
Magnesium
27. 27
Surgical Treatment
Minimally invasive techniques
ESWL (lithotripsy)
Intracarporeal lithotripsy
PCNL
URS / LC
Open surgical techniques
Pyelolithotomy
Nephrolithotomy
Pyelo-nephrolithotomy
Partial Nephrectomy
Correction of associated anatomic
abnormality e.g. pyeloplasty of PUJ
obstruction