stone disease ( brief overview ) dr. sunil shroff, ms, frcs (uk), d.urol (lond.), professor &...
TRANSCRIPT
STONE DISEASE
( Brief Overview )
Dr. Sunil Shroff, MS, FRCS (UK), D.Urol (Lond.),
Professor & HOD, Dept. of Urology,
Sri Ramachandra Medical College & Research Institution
Consultant Urologist & Renal Transplant Surgeon,
Sri Ramachandra Hospital, Porur, Madras.
COMPARATIVE INCIDENCES OF FORMS OF URINARY LITHIASIS
Stone analysis in Percentage
Form of Lithiasis India USA Japan UK
Pure Calcium Oxalate 86.1 33 17.4 39.4
Mixed Calcium Oxalate and 4.9 34 50.8 20.2
Phosphate
Magnesium Ammonium 2.7 15 17.4 15.4
Phosphate (Struvite )
Uric Acid 1.2 8.0 4.4 8.0
Cystine 0.4 3.0 1.0 2.8
Cause of Stone Disease
• Supersaturation of urine is the key to stone formation
• Intermittent supersaturation - Dehydration
• Crystal aggregation
• Anatomic Abnormailities – PUJ , MSK
• Bacterial Infection
• Defects in transport of Calcium and Oxalate by Renal
epithelia
E.Coli infection increases matrix content in urine . Proteus makes urine alkaline
Inhibitors & Promoters of Stone Formation in Urine
INHIBITORSInhibits crystal Growth -
• Citrate – complexes with Ca
• Magnesium – complexes with oxalates
• Pyrphosphate - complexes with Ca
• Zinc
Inhibits crystal Aggregation
• Glycosaminoglycans
• Nephrocalcin
• Tamm- Horsfall Protein
PROMOTERS• Bacterial Infection• Matrix • Anatomic Abnormalities – PUJ
obst., MSK • Altered Ca and oxalate transport
in renal epithelia • Prolonged immobilisation• Increased uric acid levels I.e
taking increased purine subs– promotes crystalisation of Ca and oxalate
• ?? Nanobacteria – seen in 97% of renal stones
SOME DISEASES ASSOCIATED WITH HYPERCALCAEMIA & HYPERCALCIURIA
Hyperparathyroidism Leukemia
Sarcoidosis Lymphoma
Multiple myeloma Myxedema
Hyperthyroidism Adrenal Insufficiency
Metastatic Malig. Neoplasm's Vit. D Intoxication
TYPES OF KIDNEY / URETER STONES
• OXALATE (CALCIUM OXALATE)
• PHOSPHATE
• URIC ACID & URATE
• CYSTINE
Uncommon Stones
XANTHINE STONES
– (Autosomal Recessive . Def of Xanthine Oxidase leading to Xanthinuria)
DIHYDROXYADENINE STONE
– ( Def. of enzyme adenine phospo ribosyl transferase )
SlLICATE STONES
– Rare in humans ( excess intake of Antacid with Mg Trisilicate. Mostly in cattle due to ingestion of Sand )
MATRIX
- Infection by Proteus - Radiolucent (all calculi have some amt ( 3%) of matrix but matrix calculus has 65% Matrix content in calculi)
Uncommon Stones
TRIAMTERENE
– Anti-hypertensive used with hydroclorothiazide – spare Potassium.
Mostly found as a nucleus in Ca oxalate or uric acid calculus
Indinavir Stones
- Drug to treat AIDS (4 to13%)
Ephedrine or Guifenesin
– Cough medicine - Radiolucent
Stones – Chemical Constituents
• Whewelite – Calcium Oxalate Monohydrate – CaC2O4-H2O
• Weddelite - Calcium Oxalate dihydrate – CaC2O4-2H2O
• Brushite – Calcium Hydrogen phosphate dihydrate – CaHPO4 2H2O
• Whitlockite - TriCalcium Phosphate – Ca2(PO4)2
• Struvite – Magnesium Ammonium hexahydrate – MgNH4PO4-6H2O
DD of Radiolucent filling defect on IVU in Ureter or Kidney
Must Know
• Uric Acid Calculus• Matrix Calculus• Sloughed Papilla• Blood Clots• TCC • Renal Cysts• Vascular Lesions
Know For Brownie Points
• Xanthine Calculus• Hydroxyadenine Calculus• Ephederine Calculus• Infection due to gas forming
Org.• Fungal Ball• Tuberculoma• Malacoplakia• Hypertrophied Papilla• Renal pseudo-tumour
OXALATE (CALCIUM OXALATE)
• ALSO CALLED MULBERRY STONE
• COVERED WITH SHARP PROJECTIONS
• SHARP MAKES KIDNEY BLEED (HAEMATURIA)
• VERY HARD
• RADIO - OPAQUE
Under microscope looks like Hourglass or Dumbbell shape if monohydrate and Like an Envelope if Dihydrate
PHOSPHATE STONE
• USUALLY CALCIUM PHOSPHATE
• SOMETIMES CALCIUM MAGNESIUM AMMONIUM
PHOSPHATE OR TRIPLE PHOSPHATE
• SMOOTH MINIMUM SYMPTOMS
• DIRTY WHITE
• RADIO - OPAQUE
Calcium Phosphate also called ‘Brushite’ appears like Needle shape under microscope
PHOSPHATE STONES
IN ALKALINE URINE
ENLARGES RAPIDLY
TAKE SHAPE OF CALYCES
STAGHORN
Struvite can form Stag-horn and appear like coffin lid under microscope
CALCIUM PHOSPHATE STONES
• Hyperparathyroidism Ca P
• Renal Tubular Acidosis K CO2
• Medullary Sponge Kidney -
PTH Hormone Promotes renal production of 1-25-dihyroxycholecalciferol – active Vit.D and also
increases absorption of Calcium and decreases Phosphorus absorption from Kidneys
URIC ACID & URATE STONE
• HARD & SMOOTH
• MULTIPLE
• YELLOW OR RED-BROWN
• RADIO - LUCENT (USE ULTRASOUND)
Under microscope appear like irregular plates or rosettes
pKa of uric acid 5.75 – at this pH 50% of uric acid insoluble.If pH falls further - uric acid more insoluble
CYSTINE STONE• AUTOSOMAL RECESIVE DISORDER
• USUALLY IN YOUNG GIRLS
• DUE TO CYSTINURIA -
• CYSTINE NOT ABSORBED BY TUBULES
• MULTIPLE
• SOFT OR HARD – can form stag-horns
• PINK OR YELLOW
• RADIO-OPAQUE
Under microscope appears like hexagonal or benezene ring – ask for first morning sample
CYSTINE STONE - Management
• High Fluid Intake and Alkalanise Urine – dissolve most of
the smaller cystine stones
• D-Pencillamine or MPG (Mercaptopropionylglycine) binds
to cystine that is soluble in urine
• Side effects of Pencillamine restricts it use – Allergic
rashes, GI problems- Nausea, Vomiting, Diarrhoea
• MPG better tolerated
• Large obstructive stones – Surgery required first
Cyanide Nitroprusside Calorimeteric Test for detecting Cystinuria. If positive do amino acid chromatography
pKa of cystine is 8.3, hence alkalinisisation above pH7.5 helps to dissolve the stones
Surgical Conditions and Stone Disease
• Regional ileitis and Ileal Bypass Surgery for eg Obesity can lead to increase oxalate absorption and stone ds
• ileostomies - In Chr. Diarrhoea with– Bicabonate loss – systemic acidosis and acidic urine – increases risk of Uric Acid stones
HISTORY
A. IS PATIENT DRINKING ENOUGH ?
B. PROFESSION
C. ENQUIRE ABOUT UTI STONES
D. FAMILY HISTORY
E. LONG ILLNESS BEDRIDDEN STONES
MANAGEMENT OF STONES
HISTORY :
A. FIND OUT IF DRINKING ENOUGH LIQUIDS
(NOT DRINKING ENOUGH IMPORTANT CAUSE
OF STONE FORMATION & GROWTH)
Urinary supersaturation of salts in concentrated urineAtleast drink 3 lits to avoid stone formation
HISTORY (Cont...)
B. ASK ABOUT THEIR PROFESSION
DEHYDRATION STONES CAN FORM e.g.
• MARATHON NEAR A FURNACE,
• BRICK - LAYER, LABOURERS & WEAVERS
• TRUCK & BUS DRIVERS
C. ENQUIRE ABOUT UTI STONES
D. FAMILY HISTORY
E. LONG ILLNESS BEDRIDDEN STONES
HISTORY (Cont...)
Zero Gravity state – astronauts on long space flights more prone to stones
CLINICAL FEATURES
1. PAIN IN 75 % OF THE CASES
“RENAL COLIC” IF SEVERE AND ACUTE
A) KIDNEY STONE
FIXED PAIN IN THE LOIN
B) URETERIC STONE
PAIN RADIATES LOIN TO GROIN
Both Stomach & Kidney supplied by celiac ganglion hence Nausea & vomiting common in renal colic
CLINICAL FEATURES (Contd....)
2) HAEMATURIA
• CAN BE FRANK
• OR ONLY FOUND ON DIP - STICK OR LAB.
3) PYURIA - IF INFECTION CAN HAVE PUS IN URINE
ON EXAMINATION
1. ACUTE PRESENTATION
• ABDOMEN TENSE AND RIGID
• TENDERNESS PRESENT IN THE LOIN
2. IN ROUTINE PRESENTATION
• NO FINDINGS IN ABDOMEN
INVESTIGATIONS
1. FULL BLOOD COUNT TO CHECK FOR
ANAEMIA IF GOING FOR SURGERY
2. SERUM ELECTROLYTES PLUS UREA /
CREATININE / CALCIUM / URIC ACID /
PHOSPHATE
INVESTIGATIONS (Cont...)
3. 24-HOURS URINE FOR ELECTROLYTES
(Only if recurrent stone former)
CALCIUM / OXALATE / URIC ACID /
CYSTINE / CITRATE
INVESTIGATIONS (Cont...)
4. PLAIN KUB X-RAY OF ABDOMEN (Mandatory)
5. IVU OR IVP (INTRA VENOUS UROGRAM)
6. ULTRASOUND (Mandatory)
INVESTIGATIONS
IVU OR IVP (INTRA VENOUS UROGRAM)• Not Mandatory• 1in 40,000 patients die due to anaphylactic reaction to
contrast• Useful for radio-lucent stones & to detect
Congenital Anomalies in Urinary tracts
INVESTIGATIONS (Cont...)
7. CT –
TO LOOK AT UNUSUAL ANATOMY OF THE KIDNEY
To differentiate cause of acute colic – stone or anuria
Suspected due to stone disease
8. DMSA OR DTPA OR MAG3 RENOGRAM - TO STUDY FUNCTION OF
EACH KIDNEY.
Bilateral Ureteric Calculus in a patient presenting with Anuria Bilateral Ureteric Calculus in a patient presenting with Anuria
Helical or Spiral CT provides 3D reconstruction. Helical refers to path the X ray follows on Gantry. These are rapidly performed and do not require contrast agents for reconstruction.
MANAGEMENT OF UROLITHIASIS
• Non-invasive approach to urinary calculas-HALLMARK of last 20 yrs.
• Lithotripters –
1.Extra Corporeal Shock wave
2.Intra Corporeal
• Better fiber optics – Miniturisation of Telescopes • Accessories - Innovative variety
Modern Management of Urolithiasis
• ESWL• Ureterorenoscopy• Percutaneous Nephrolithotomy• Laparoscopic Approach to stones
Open Ureterolithotomy, Pyelolithotomy or Nephropyelolithotomy is required in less than 1 to 2% of modern stone management
TREATMENT (IDEALLY)
MAJORITY : 80 TO 85 % of all stones can be treated by -
EXTRA - CORPOREAL SHOCK WAVE LITHOTRIPSY (ESWL)
MINORITY : 15 TO 20 % SHOULD NEED MINIMALLY
INVASIVE SURGERY (PCNL / URETEROSCOPY)
(LESS THAN 1 % SHOULD NEED OPEN SURGERY)
EXTRA - CORPOREAL SHOCK WAVE LITHOTRIPSY(ESWL)
SHOCK WAVES GENERATED UNDER WATER CAN
TRAVEL THROUGH BODY WITHOUT ANY APPRECIABLE
LOSS OF ENERGY. WHEN THEY ENCOUNTER STONES
THE CHANGES IN DENSITY CAUSES ENERGY TO BE
ABSORBED AND REFLECTED BY THE STONE & THIS
RESULTS IN FRAGMENTATION OF THE STONES.
ESWL – For Urinary Tract CalculusESWL – For Urinary Tract Calculus
ESWL- FOUR MAIN ELEMENTS
1. ENERGY SOURCE
2. FOCUSING DEVICE
3. COUPLING DEVICE
4. LOCALIZATION DEVICE
ESWL
Absolute Contra-indication-Pregnancy
Relative Contra-Indications for ESWL –
• Renal Colic• Urinary obstruction • Infection• Declining Renal Function• Significant Hematuria
COUPLING DEVICE
“WATER BATH”
“WATER FILLED CUSHION”
(KEEP PATIENT’S DRY)
ESWL-HISTORY
1963-EXPERIMENTS WITH “ SHORT WAVES” IN W.GERMANY BY PHYSICISTS AT DONIER SYSTEMS LTD
1980-DORNIER HUMAN MODEL ( HM-3)
LITHOTRIPTER ARRIVED ON MARKET
(STILL GOLD STANDARD WHEN COMPARING RESULTS WITH NEW MEASUREMENTS
ESWL & STAGHORNS
• Dornier HM-3 Monotherapy for STAGSHORNS -
30% Stone Free Rate (In Dilated Collecting System )• PCNL has higher overall Success• Combination of PCNL & ESWL can give a
stone free rates of 90% For ALL STONES IN THE KIDNEY
COMPRESSION-TENSILE WAVE CAUSES:
“Implosion” Rather than “Explosion”
ESWL & URETERIC CALCULI
• For fragmentation fluid medium around stone necessary
• If stones impacted fragmentation may not occur
• “PUSH & BANG”-success Marginally HIGHER THAN “in situ ESWL”
• Trial of “in situ ESWL” – first choice • “In situ ESWL” FAILS- “Rescue procedure”
ESWL COMPLICATIONS
• Haematuria – is quite common ( short term antibiotics Recommended )
• Incomplete stone Fragmentation & Obstruction• “Stienstrasse” ( stone street ) usually due to a
large “ Leading fragment”
( Stents Recommended prior to ESWL for Calculi > 1.5 cm )
DESIGN BASIC LITHOTRIPSY
Renal Lithiasis Blood Pressure Study ( Patients treated 1984-1986
Dallus Study)
First Follow Up Second Follow Up
1988 1990
No.Pts Annualized Rate No.Pts Annualized Rate of Hypertension of Hypertension
ESWL 771 2.5% 590 2.1%
non-ESWL 195 3.8% 155 1.6%
Total 966 745
Basic Principles of
“SHOCK WAVE”
Lithotripsy
FRAGMENTATION BY SHOCK WAVES
ON COLLISION OF “ SHOCK WAVES” WITH CALCULI-
• ON FRONT SURFACE – COMPRESIVE FORCES• ON BACK SURFACE OF THE STONE-
REFLECTION OF COMPRESSION PULSE CREATES NEGATIVE OR TENSILE WAVE THAT TRAVEL BACK WARD THROUGH CALCULI
• ONCE TENSILE FORCE EXCEEDS “ COHESIVE STRENGTH” OF CALCULI- FRAGMENTATION OCCURS
ESWL – SPARK GAP/ EHL
• Electro-hydraulic Generator Located at Base of Water Bath
• Produces Shock wave by Electric Spark Gap of 15,000 to 25,000 Volts Lasting 1 Sec
• High Voltage Spark Discharge Rapidly-
evaporates Water & Generators A “Shock Wave” by expanding Sarrounding Liquid
Mechanism of Stone Fragmentation by ESWL
• On Front Surface – Compresive or positive Forces• On Back Surface Of The Stone-
Reflection Of Compression Pulse Creates Negative Or Tensile Wave That Travel Back Ward Through Calculi
• Once Tensile Force Exceeds “ Cohesive Strength” Of Calculi- Fragmentation Occurs
• Cavitation – Small air bubbles
Steinstrasse ( or Stone Street) – Post ESWL
Diet & Fluid Advice
• High Fluid Intake
• Restrict Salt (Na)
• Oxalate Restrict
• Avoid high intake of Purine food
• Increased citrus fruits may help
• If hypercalciuria restrict Ca intake
Role of Potassium Citrate in preventing Cal Oxalate stone ds – KCit lowers
urinary calcium whereas Na Citrate does not lower Calcium due to Sodium load
LIQUIDS
Moderate Amounts : High Amounts :
Apple Juice Cocoa
Beer Fresh Tea
Coffee
Cola
FOODS :
Almonds, Asparagus, Cashew Nuts, Currants, Greens,
Plums, Raspberries, Spinach
HIPPOCRATIC OATH :
“I Will not cut, even for the stone, but leave such
procedures for the practitioners of the craft”