Sunday, October 28, 2007

Renal Stones (CPC)

Renal Stones


Introduction&Etiology
By
Aisha Masood
Kidney Stones

Kidney stones are Solid accretions(Crystals) of dissolved minerals in urine found inside the kidneys or ureter also known as Nephrolithiasis, Urolithiasis or Renal calculi
Incidence
•12% of the world population will have renal stones at some point in their lives
•By the age of 70 yrs Male-Female ratio is 12:5
•Peak incidence is in the 2nd and 3rd decades of life.
•Bilateral Renal calculi occur in 10-15% of the patients
•Recurrent stone formation in patients with history of renal stones
–50% within 5-10 yrs
–80% in their lifetime
Prevalence
•Increases with age attaining maximum in 40-50 yrs of life

•Much earlier in white and somewhat later in non-whites

•Decreases after the age of 60 yrs

•Approaches ZERO by 9th decade
Disease Burden in Pakistan
•Every 5th person over the age of 40 yrs is affected by chronic kidney diseases including renal stone

•Male – female ratio is 2:1

•Prevalence of silent kidney stones is 3%

What are kidney stones made of…??
•Kidney Stones consist of a center that contains crystal like substances

•Surrounding region is composed of Layers

•Kidney stones are composed of different chemical substances. Each of major types is named for its main chemical ingredient

Pathogenesis
Decreased urinary Volume
Increased excretion of Stone “Ingredients”
Etiology

General Etiology
v Diet:
v Excessive Milk
v Oxalate containing foods
v Vitamin A deficiency
v Deficiency of Inhibitors of crystallization
v Stasis of urine
v UTIs
v Hot Weather and Dehydration
v Randall’s Plaques

v Prolonged immobilization

v Hyper-Parathyroidism & Ectopic paratharmone secretion

v Vitamin-D intoxication

v Milk-Alkali Syndrome
Specific Etiology
This concerns etiology of individual type of stone
Calcium oxalate Stones
•Idiopathic
•Genetic

•Hypercalciuria
Absortive,
Renal
Resorbtive
Certain cancers
Sarcoidosis
drugs


Hyperoxaluria
primary (inherited)
enteric
def. of hormones
dietary oxalates
•Hypercalcemia
Hyperparathyroidism
Immobilization
Renal tubular acidosis

•Hypocitraturia
Renal tubular acidosis
K and Mg def.
UTI
Kidney failure
Chronic diarrhia


•Nano-Bacteria infection
Uric Acid Stones
•Hyperuricosuria
–Genetic factors
–Diet overly rich in animal proteins
–Gout
–Certain medication
–Fasting
–Lead toxicity
–Blood Diseases
–Chronic Diarrohea
Struvite Stones
•UTIs

Risk Factors
•Geographical factors

•Genetics
–Caucasian Men
–Congenital Malformations
–Inherited Factors
–Family History of gout and Renal Stones

•Women During Pregnancy

•LBW babies
•Life Style
–Diet
–Obesity
–Stressful life
–Sleeping posture
–Immobilization

•Drugs

•Inadequate hydration

•Infections
•Systemic Diseases
–HTN
–Hyperparathyroidism
–Kidney Diseases
–Chronic Diarrhoea
–Certain cancers
–Sarcoidosis
–HIV AIDS patients
Types of Renal Calculi&Clinical Features

By
Sosan Andaleeb
Types of Renal Calculi
•Calcium Calculi

•Struvite Calculi

•Uric Acid and Urate Calculi

•Cystine Calculi

•Xanthine Calculi

•Crixivan Calculi

•Dihydroxyadenine Calculi
Calcium Stones
Composition: Calcium Oxalate and Ca3 (PO4)2
Incidence: 40-80%
Shape: Irregular
Size: Variable
Surface: Sharp projections
Colour: Surface discoloured by blood
Consistency: Very Hard
Radiography: Radio-Opaque
Calcium Oxalate Stone
Struvite Stones
•Composition:Mg-NH4-PO4 , Carbonate Apatite [CaCO3 and Ca3 (PO4)2]
•Incidence: 7-31%
•Shape: Variable
•Surface: Smooth
•Size: Small to large Stag Horn Calculi
•Colour: Dirty White
•Consistency: Hard
•Radiography: Radio-Opaque
Staghorn Stone
Conditions with Struvite Stones
•Commonly called Infectious Stones
•Infectious agents are the urease splitting bacteria (Proteus, Klebsiella, Pseudomonas and rarely Staph. Aureus)
•Tend to grow in Alkaline Urine
•Even a large stone may be symptomless for years
•It may signal its presence by Hematuria, Intractable UTI and Renal Failure
Uric Acid Stone
Composition: Uric Acid, Ammonium Sodium Urate and some Calcium
Incidence: 5-10%
Shape: Round
Surface: Multifaceted and smooth
Size: Variable
Colour: Yellow to Reddish brown
Consistency: Hard
Radiography: Radiolucent but sometimes faintly radio-opaque due to some calcium.
Uric Acid Stone
Cystine Calculi

Composition: Cystine
Incidence: 1-4% (Adults), 6-8% (Children)
Shape: Irregular
Size: Small to large
Surface: Rough
Colour: Pink/yellow but Green in air
Consistency: Very Hard
Radiography: Radio-opaque
Cystine Stone
Xanthine Calculi
Composition: Xanthine and Hypoxanthine
Incidence: Extremely rare
Shape: Irregular
Size: Variable
Surface: Porous
Colour: Yellowish brown
Consistency: Hard
Radiography: Radiolucent but sometimes radio-opaque
Xanthine Stone
Crixivan Calculi
•Resuls with the use of Indinavir Sulphate (Crixivan) a protease Inhibitor in HIV patients
•Act as a nidus for heterogenous nucleation leading to development of mixed stones
•Indinavir therapy averaged 5-6 months prior to development of renal colic
•Typically radiolucent
•Radiolucency and gelatinous nature make lithotripsy difficult and poor choice of treatment
Crixivan Stone
DHA Stones
•Associated with Dehydroxy-Adeninuria
•Metabolic Disorder due to deficiency of Phosphoribosyl Transferase
•Primarily identified in children
•Similar to uric acid stones in that they are radiolucent but they are much more soluable in acidic pH.
Symptoms
•Variable Symptoms
•Silent calculi
•Pain
–Dull Fixed Flank Pain
–Ureteric Colic
•Dysuria
•Hematuria
•Pyuria
•Urinary Retention
•Rigors and Fever
•Nausea and Vomiting

Renal Colic & Referred Pain
Hematuria
Signs
•Swelling
•Tenderness
•Rigidity
•Sweating.
•Tachycardia
•Tachypnoea
•Blood pressure is elevated due to the severe discomfort.
Investigations ofRenal Calculi
By
Alaman Shaukat
STEP 1
•HISTORY AND GPE

•ROUTINE BASELINE LAB. INVESTIGATIONS

•PLAIN ABD. X-RAY (KUB)
HISTORY

•FRQUENCY OF STONE FORMATION
•ANALYSIS OF PREVIOUS STONE (IF ANY)
•PRESENCE OF RECURRENT UTI
•FAMILY HISTORY OF
lSTONE DISEASE
lPARATHYROID DISEASE
lGOUT
•OCCUPATIONAL HISTORY PARTICULARLY WHERE EXCESSIVE SWEATING OCCURS
•DIETARY HISTORY
•MEDICAL AND SURGICAL RISK FACTORS
•IMMOBILIZATION
•CONDITIONS PREDISPOSING TO HYPERCALCEMIA AND HYPERCALCIURIA
•MEDICATIONS
PHYSICAL EXAMINATION
•CHECK FOR HYPERTENSION RESULTING FROM THE DISCOMFORT

•PALPATE THE PATIENTS ABDOMEN ESPECIALLY THE FLANK AREA WHERE AN EARLY HYDRONEPHROTIC KIDNEY MAY BE PALPABLE

•TENDERNESS AT THE COSTOVERTEBRAL JUNCTION AT THE BACK

•BLADDER SHOULD BE PERCUSSED AS URINARY RETENTION IS NOT INFREQUENT ESP. WITH ACUTE URETERAL COLIC DUE TO INTRAMURAL URETER OBSTRUCTION

•BOWEL SOUNDS CAN BE HYPOACTIVE AND AN ILEUS CAN BE PRESENT CLINICALLY AND RADIOGRAPHICALLY
ROUTINE BASELINE LAB INVESTIGATIONS
BLOOD:
HB%
FBC
GLUCOSE
UREA
URIC ACID

URINE R/E:
COLOR/TURBIDITY/ SP. GRAVITY
pH
MICROSCOPY AND CULTURE
RBCs
CALCIUM
OXALATES
URIC ACID
DIAGNOSTIC PROCEDURES
PLAIN ABDOMINAL X-RAY(KUB)
A KUB IS A PLAIN ABDOMINAL FILM WHERE THE INITIALS K-U-B STANDS FOR KIDNEY-URETER-BLADDER.ITS A ROUTINELY CARRIED OUT PROCEDURE THAT IS CHEAP AND ABLE TO PICK UP 90% OF THE STONES

ADVANTAGES:
•FIRST LINE INVESTIGATION PROCESS. EASY TO CARRY OUT AND QUICKLY PERFORMED

•NO CONTRAST IS GIVEN.

•MAJORITY OF STONES BEING RADIOOPAQUE(90%) ARE PICKED UP

•CHEAP

DISADVANTAGES:
•CANNOT VISUALIZE RADIOLUCENT STONES

•CANNOT DETECT STRUCTURAL AND PHYSIOLOGICAL CHANGES IN THE COLLECTING SYSTEM OF THE KIDNEY i.e. PELVIS, URETER.

•RADIATION HAZARD.CONTR-INDICATED IN PREGNANT WOMEN

•MAY NOT VISUALIZE SMALL RADIO-OPAQUE STONES OR THOSE OVERLYING VERTEBRAL PROCESSES, PELVIC BONES etc.


KUBs
STEP2

•EXCRETION UROGRAPHY
–Intravenous urography
–Ante grade pyelography
–Retrograde pyelography
INTRAVENOUS UROGRAPHY

•PATIENT HAS TO BE EXPLAINED THE PROCEDURE FOREHAND AND CONSENT TAKEN

•HE/SHE HAS TO BE N B M 8-12 hrs BEFORE THE TEST

•A POSSIBLE ALLERGIC RESPONSE MUST BE IN MIND OF THE PHYSICIAN THEREFORE NECESSARY EMERGENCY MEASURES MUST BE AT HAND

•AN IODINE BASED RADIO-CONTRAST DYE IS INJECTED INTO AN ANTI-CUBITAL VEIN OF THE FOREARM.

•SEVERAL FILMS ARE TAKEN AT INTERVALS, AS THE DYE IS EXCRETED BY THE KIDNEYS AND OUTLINE THE URINARY TRACT.
ADVANTAGES:
•FILLING DEFECTS MAY HINT TOWARDS RADIOLUCENT STONES OR SMALL RADIOOPAQUE STONES IN THE URETER OBSTRUCTING THE OUTFLOW

•STRUCTURAL OUTLINE OF PELVICALYCEAL SYSTEM AND URETER IS MADE.

•A RELATIVELY INEXPENSIVE PROCESS.

DISADVANTAGES:
•TEMPORARY SIDE EFECTS. E.g. METALLIC TASTE, BURNING SENSATION AT SITE OF ADMIN.
•DANGER OF AN ALLERGIC RESPONSE TO THE IODINE BASED RADIO CONTRAST DYE USED IN THE PROCEDURE
•CUTAIN EFFECT
•A TIME CONSUMING PROCESS. APPROX.80 MINUTES.
•A PRIOR RENAL FUNCTON TEST LIKE CREATININE CLEARANCE IS IMPORTANT. CUT OFF POINT IS A SER.CREATINE LEVEL OF 2.5mg/dl
•CONTRA-INDICATED IN PREGNANT LADIES.
•SERIOUS SIDE EFFECTS LIKE NEPHROTOXICITY CAN COMPLICATE THE PROCEDURE

RETROGRADE PYELOGRAPHY
•SINCE THE DYE DOESN’T ENTER THE BLOOD STREAM THE CHANCE OF AN ALLERGIC RESPONSE IS SMALL

•WHERE THE PERCUTANEOUS ROUTE FOR ANTEGRADE PYELOGRAPHY CANNOT BE USED THERE WE GO FOR THE RETROGRADE PYELOGRAPHY.
PYELOGRAM
STEP 3

•ULTRASONOGRAPHY
•ULTRA SOUND WAVES ARE HIGH FREQUENCY WAVES RANGING IN MEGAHERTZ(MHZ).

•A TRANSDUCER DIRECTING THE WAVES IS PUT IN CONTACT WITH THE BODY SURFACE OVER THE TARGET AREA(ORGANS).

•ALL STRUCTURES WITHIN THE BODY CAVITY REFLECTS(ECHOES) THE WAVES BACK AT THE RECEIVER WITH DIFFERENTIAL STRENGTH DEPENDING UPON THEIR DENSITY AND COMPOSITE..

•THE WAVES ARE TRANSLATED AS HYPERECHOIC (MORE WHITE) OR HYPO-ECHOIC (DARKER) AREAS CORRESPONDING TO THE REFLECTING SURFACE.

ADVANTAGES:
•GOOD ANATOMICAL DETAIL IN A SHORT PERIOD OF TIME

•NO EXPOSURE TO RADIATION

•NO USE OF INTRAVENOUS CONTRAST DYE

•DECLARED AS SAFE IN OBSTETRIC PATIENTS.

•WITH TRANSDUCERS OF (6.5-20 MHZ) CALCULI AS LITTLE AS 3mm ARE DETECTABLE

DISADVANTAGES:
•POOR VISUALISATION OF CALCIFICATIONS OR STONES IN URETER
•LACK OF ASSESSMENT OF RENAL FUNCTION
•THE NEED OF A FULL BLADDER TO DETECT OBSTRUCTION AS URETERO-VISCAL JUNCTION
•ACUTE URETERIC COLIC WITH ABSENCE OF PELVICALYCEAL DILATATION MAY GIVE FALSE NEGATIVE RESULTS
•LIMITED ROLE IN THE DIAGNOSIS OF OTHER PATHOLOGY IN ABSENCE OF URETERAL STONES
STEP 4
•HELICAL/ SPIRAL CT

•DOPPLER STUDIES
HELICAL/SPIRAL CT
•CT SCAN IS AN ADVANCED PICTURE OF AN X-RAY GIVING A GREATER INSIGHT OF THE BODY ANATOMY

•HELICAL/SPIRAL CT IS A CONTINUOUS SLICING PROCESS WITH THE ABILITY TO SCAN VERY THIN SECTIONS UPTO 1mm. THUS MINUTE PATHOLOGIES CAN BE IDENTIFIED .
ADVANTAGES:
•RAPID SPEED, ACCURACY AND ABILITY TO MAP THE ABDOMEN
•THIN SECTIONS TO PICK UP VERY SMALL CALCULI
•QUICKER THAN IVU. AVERAGE TIME IS 5MINUTES. ITS ABOUT 80 MINUTES FOR ANA IVU
•RISKS OF CONTRAST REACTIONS ARE ELIMINATED
•BOTH RADIOLUCENT AND RADIO OPAQUE STONES CAN BE IDENTIFIED
•RADIATIONS DOSE IS LESS THAN OR EQUIVILANT TO IVU
•CT AVOIDS THE NEED FOR CREATININE CLEARANCE UNLIKE IVU WHERE RENAL FUNCTION HAS TO BE ASCERTAINED
•CAN IMAGE ADJACENT ORGANS
OVER ULTRASONOGRAPHY:
•CAN DIFFFERENTIATE OTHER CAUSES OF URETERIC COLIC LIKE PYELONEPHRITIS, RENAL CELL CARCINOMA, PERINEPHRIC HEMATOMA, TRANSITIONAL CELL CARCINOMA, UPJ OBSTRUCTION AND BLADDER CYSTITIS

•CAN DETECT WIDE RANGE OF PATHOLOGIES OUTSIDE THE SPECTRUM OF GENITO-URINARY SYSTEM THAT CAN MIMIC THE CLINICAL PRESENTATIONS OF CALCULI LIKE DIVERTICULITIS, ADNEXAL MASSES, RENAL ARTERY ANEURYSMS, VERTEBRAL MASSES.

CT Scans

DISADVANTAGES:
•DOES NOT GIVE PHYSIOLOGIC EVIDENCE OF OBSTRUCTION
•DOES NOT VISUALIZE THE COLLECTING SYSTEM TO EVALUATE HEMATURIA
•UNABLE TO IDENTIFY PURE MATRIX STONES OF MUCIN AND FIBRONECTIN
•UNABLE TO IDENTIFY CRIXIVAN STONES
•COST FACTOR
DOPPLER STUDIES
ADVANTAGES:
•ABILITY TO DEFINE THE PHYSIOLOGICAL STATUS OF THE KIDNEY

•THE RENAL BLOOD FLOW AND EXCRETARY OUTFLOW (URETERAL JET) CAN BE EVALUATED AT THE SAME TIME

STEP 5
•RENAL SCANS
•DTPA
•DMSA
RENAL SCANS
DTPA
•DTPA (DIETHLYENE TRIAMINE PENTA ACETIC ACID) IS A DYNAMIC SCAN PROCESS TO EVALUATE THE PHYSIOLOGICAL STATUS OF THE KIDNEY.

•IT IS LABELLED TO Tc-99 AND IS CLEARED LIKE INULIN BY THE KIDNEY.THE INVESTIGATION GIVES INFORMATION ABOUT BLOOD FLOW TO THE KIDNEYS AND HOW EACH KIDNEY IS FUNCTIONING TO PRODUCE URINE.

•THE PATIENT IS TAKEN TO THE SCAN ROOM AND ASKED TO LIE ON A COUCH. ITS UNNECESSARY TO UNDRESS.

•A GAMMA CAMERA IS POSITIONED UNDER THE PATIENT.SINCE IT’S A DYNAMIC PROCESS THE PATIENT HAS TO STAY POSITIONED TILL THE END OF THE SCAN PROCESS

DMSA SCAN
•DMSA (DIMERCAPTO-SUCCINIC ACID SCAN) ALSO CALLED A STATIC RENAL SCAN.IT GIVES INFORMATION ON THE SIZE,SHAPE AND POSITION OF THE KIDNEY. ALSO ON THE PRESENCE OF SCARS etc....

•PATIENT IS INJECTED WITH THE DYE AND TOLD TO LEAVE IF HE WISHES TO DO SO .

•EXPLAINED TO RETURN AFTER 3 hrs. THEN A GAMMA SCANNER TAKES SEVERAL SCANS SIMULTANEOUSLY AS BY THE TIME THE KIDNEY (or its viable parts) HAS ABSORBED THE DYE.

FINALLY !
•STONE ANALYSIS & POST ANALYSIS INVESTIGATIONS.
STONE ANALYSIS AND POST ANALYSIS INVESTIGATIONS
CALCIUM OXALATE/PHOSPHATE STONES
•BONE DENSITY SCAN
•PTH ASSAYS
•URINE CITRATE LEVELS-(300-900 mg/24HRS 1.6-4.7 mmol/24 hrs important)
ADVANCED INVESTIGATIONS:
•GENE PROBING
•DEFECTIVE GENE REGULATING CALCITRIOL:
THE DEFECTIVE GENE CAUSE AN EXCESS OF CALCITRIOL LEADING TO EXCESS ABSORPTION OF CALCIUM
•DEFECTIVE CLCN5 GENE:
CLORIDE WITH A NEGATIVE CHARGE AND CALCIUM WITH A POSITIVE CHARGE ARE USED TO BALANCE EACH OTHER OUT. EXCESS OF CHLORIDE IN URINE LEADS TO EXCESS OF CALCIUM IN URINE TOO.

OXALATE EXCESS:
•PRIMARY HYPEROXALURIA TYPE 1 & 2
•DEFICIENCY OF VIT.B6(PYRIDOXINE)
•SHORT BOWEL SYNDROME, CROHN’S DISEASE etc.

URIC ACID STONES:
HYPERURICEMIA
•GOUT
•INCREASED CELL TURNOVER



STRUVITE:
•URINE Ph
•CULTURE AND MICROSCOPY

CYSTINE STONES:
•INVESTIGATE CYSTINURIA
•RAPID SCREENING NITROPRUSSIDE TEST
•24 hrs CYSTINE EXCRETION
Management of Renal Stones
By
Muhammad Jawad ul Qamar
Goals of Management

•To Control symptoms

•Render the patient stone free

•Prevent recurrence.

Rules of Management

•Management of a kidney stone depends upon
–Size of stone
–Location of stone
–Composition of stone
–Presence of anatomical malformation
–Complications.

•Initial management can either be done as an inpatient or an urgent outpatient basis
Indications for Hospital Admission
•Fever

•Solitary Kidney

•Known non functioning kidney

•Inadequate pain relief or persistent pain

•Poor social support

•Inability to arrange urgent OPD follow-up

Indication for OPD Intervention
•Pain has been relieved

•Patient able to drink large volumes of fluid

•Adequate social circumstances

•No complications evident
Modes of Management

•Conservative Management

•Medical Management

•Surgical Management
1. Conservative Approach
Conservative Approach
•Why conservative approach…??

•Wait for 1-3 weeks.

•Should be assessed by a KUB every 1-2 weeks to monitor progression.

•Urgent intervention indicated for:
–Intractable symptoms
–Infection
–Obstruction

2. Medical Management
Modes of Medical Management

•General

•Specific
General Medical Management
•Fluid Intake
•Intake of Citrate Supplements
•Avoid Oxalate-Rich Diets
•Moderate Calcium-Containing Foods
•Reduced Dietary Salt Intake
•Reduced Acid Ash Diet
•Increased Dietary Magnesium
•Nutritional Supplement

Fluid Intake
Increase in total urine volume
(Atleast 2 liters)



Decrease in the total concentration of crystals in the urine


Decreased Chances of Stone Formation


Hydration - Single most important preventive factor

Citrate Supplements

Increased Urinary levels of citrate



Binding of Calcium with Citrate



Inhibition of Oxalate and Phosphate Stone formation

Increased metabolism to Bicarbonate



More alkaline urine




Decreased chances of uric acid stones
Oxalate Diet Restriction

Limit the level of dietary oxalate.


Decreased Urinary Oxalate


Decreased Urinary calcium oxalate crystals

Calcium Containing Foods
Excessive amounts of dietary calcium


Increase the risk of stone formation
Moderate amounts of dietry calcium


Protective effect against Calcium Stones
Dietary Salt Intake
Decreased Reabsorption of calcium from the renal tubules





Increased calcium in the urine.


Indirectly lower total urinary citrate levels



Increased Oxalate binding and decreased pH

Moderate Protein Diet
Excessive amounts of Animal Proteins


Increased the risk of stone formation
Moderate amounts of Animal Protein


Protective effect against Calcium and Uric Acid Stones
Increased Dietary Magnesium Intake
Increased binding of oxalate in urine



Decreased availability of oxalate in the urine.


Indirectly Increase total urinary citrate levels



Increased Oxalate binding and Increased pH

Nutritional Supplements
•High risk patients for Calcium stones should avoid use of:
–High levels of Vitamin C or Ascorbic Acid
–Large doses of Vitmin D
–Increased intake of Ca Supplements

•High risk patients for Uric acid stones should decrease the use of Protein supplements
Specific Medical Treatment
•Polycitra-K
•Urocit-K

•Allopurinol

•Lithostat

•Thiola

•Other Medication

3. Surgical Management
Indications for Surgery
Surgery should be reserved as an option for cases where other approaches have failed or should not be tried.

Surgery may be needed if a stone:

•Does not pass after a reasonable period of time
•Is too large to pass on its own
•Causes constant pain
•Blocks the flow of urine
•Causes ongoing urinary tract infection
•Damages kidney tissue or causes constant bleeding
•Has grown larger (as seen as follow-up X-ray studies)
Surgical Management
•Stenting
•Extracorporeal ShockWave Lithotripsy (ESWL)
•Electrohydraulic Lithotripsy (EHL)
•Ultrasonic Lithotripsy
•Pneumatic Mechanical Lithotripsy
•Laser Lithotripsy
–Holmium Laser Lithotripsy
–Alexandrite Laser Lithotripsy
–Coumarin-Dye Laser Lithotripsy
•Percutaneous Nephrolithotomy
•Sandwich Therapy
•Laparoscopic Surgery
•Open Surgery
Stenting
•Ureteral Stents are tubular indwelling devices designed to provide support and maintain patency of the ureter, which may be blocked or obstructed

•The indications for placement of a ureteral stent are:
–Ureteral stricture
–Obstruction by a stone
–Tumor.
–A repair or surgical anastomosis of a ureter
ESWL(ExtraCorporal Shock Wave Lithotripsy)

•Management revolutionized by advent of Lithotripters
•A reliable and efficient outpatient treatment option for urinary calculi less than 2 cm in diameter.
•Intravenous sedation-analgesia or Local Anesthetic creams for decreasing pain
•Transient effects on Renal Hemodynamics, Functional level and enzymatic Activity
•The only absolute contraindication is pregnancy
•Complications include Hematuria, Renal and Peri-Renal Hematoma, Obstruction, Ureteral colic and Infection
ESWL Machine

KUB After ESWL Session
•Following ESWL, a patient developed RLQ pain. This KUB shows the collection of stones in the distal right ureter noted by the red arrowheads. A stent was placed to unblock the kidney (yellow arrowheads).

Electro-Hydaulic Lithotripsy
•Electrohydraulic lithotripsy (EHL) was the first form of contact intra-corporal lithotripsy developed.
•Utilizes a probe containing two electrodes separated by an area of insulation.
•A spark gap is created by electric current, causing shockwave.
•This process is exactly similar to shock wave lithotripsy however EHL is not focussed

Advantages of EHL
•Widely available
•Inexpensive

Disadvantages of EHL
•Perforate of the ureteral wall
•Probe deterioration with shedding pieces of insulation
•Possible break off of probe requiring retrieval of the device.
•This device is not reusable.
•EHL may be ineffective against some stones.

Ultrasonic Lithotripsy
•Ultrasonic lithotriptors are very effective in treating large stones.

•Fragmentation and suction of stone particles occur simultaneously.

•The large size of these probes requires passage through large, rigid endoscopes
Ultrasonic Lithotripsy Machine
Ultrasonic Lithotripsy
Ultrasonic Lithotripter
Advantages and Disadvantages
Advantages of Ultrasonic Lithotripsy
•Easy to use
•Results are excellent with stone free rates of 95-100%
•Excellent modality for percutaneous stone removal

Disadvantages of Ultrasonic Lithotripsy
•May cause movement of the stone or fragments in the ureter
•Continuous irrigation is necessary to offset the heat generated by the devise
•Because the ultrasound requires a relatively large, rigid instrument, most stones treated are limited to the lower ureter.
Pneumatic Mechanical Lithotripser
•Several pneumatic lithotriptors are in current use.
•In the Swiss Lithoclast compressed air repeatedly drives a metal bullet onto a metal rod creating a chisel and hammer effect that fragments the targeted stone.
•The Lithoclast and the Browne Pneumatic Impactor (BPI) are capable of fragmenting all stones, irrespective of their size or composition.
•Unlike laser and ultrasonic lithotriptors, there are no thermal sequelae.
•Pneumatic lithotripsy utilizes compressed air forcing a metal projectile against a probe, which causes the probe to move back and forth very quickly, resulting in a "jackhammer" effect to fragment the stone.

Pneumatic Mechanical Lithotripter
Advantages and Disadvantages
Advantages of Pneumatic Lithotripsy
•Simple to use
•No disposable parts
•Easy to maintain
•Relatively inexpensive
•Pneumatic lithotripsy comes in both rigid and flexible fibers and can be utilized in rigid and flexible ureteroscopy

Disadvantages
•A tendency to propel the stone or fragmented stone toward the upper ureter
•Flexible fibers may have some decline in force compared to a standard rigid probes

Holmium laser Lithotripsy
•The Holmium:YAG (Ho:YAG) are used for fragmentation of urinary calculi through miniaturized rigid and flexible endoscopes.
•The Ho:YAG laser is effective at fragmenting all stones types.
•It can also cut a stone basket or the wall of a ureter if contact occurs.

•Holmium:YAG laser utilizes a wavelength in the infrared zone (2100 microns). This laser creates a vapor "tunnel" in the irrigating fluid. The laser works on the surface of the stone by vaporizing water and organic matter in the stone resulting in destruction in the urinary calculus.
Holmium Laser Lithotripter
Laser Function
Laser Lithotripsy
Example of Laser Lithotripsy
Advantages and Disadvantages
Advantages of Holmium:YAG Laser
•Works by fragmentation or by vaporization
•This laser devise is easy to use
•It is ready to use within one minute after it is turned on
•No special non-conduction solution is required
•The fiber can be placed with great precision and controlled action
•Protective eye ware does not compromise the ureteroscopic view of the stone or fiber
•The machine is readily moved from one operating room to another
•The laser fibers are versatile and can be used in rigid or flexible ureteroscopes
•This laser can be used with high efficacy regardless of stone composition
•This laser reduces the need for stone manipulation or basketing

Disadvantages
•Destruction of large stones can be tedious and time consuming
•The laser will melt the wires of a basket or guide wire if fired directly onto the wire making extraction of the basket or wire difficult

Alexandrite laser Lithotripsy
The Alexandrite laser lithotripsy utilizes a wavelength of 755 nm.

Advantages of Alexandrite Laser Lithotripsy
•A reliable devise
•Minimal maintenance required
•Protective eye ware causes mild, red/green color confusion but less pronounced than that noticed with Coumarin dye laser
•Less likely to damage the ureteral wall
•This laser will not melt wires of a basket or guidewire

Alexandrite Laser Machine
Coumarin Dye Laser Lithotripsy
•The pulse-dye laser is safe and effective in the treatment of impacted ureteral stones.
•Relatively ineffective against cystine calculi.
•Coumarin dye (wavelength of 504 microns) laser lithotripsy is a flash-lamp pump laser using coumarin green dye as a laser medium. At this wavelength, this laser will have the maximum effect on the stone and a minimal effect of the ureteral wall.
•When the stone absorbs the laser light, a smaller amount of heat is generated which creates a cavitation bubble.
•The expansion and contraction of this bubble creates acoustic waves, which pass into the stone resulting in fragmentation.
Advantages and Disadvantages
Advantages
•Laser is safe and effective
•Laser does not damage the ureteral wall
•Will not damage guide wires or baskets

Disadvantages
•Difficulty in fragmenting calcium oxalate monohydrate stones
•Cystine stones will not fragment
•Less effective than Holmium laser
•Requires eye protection
•The machine requires turning on in advanced (20 minutes) of procedure
•Maintenance is frequent and expensive
•Initial capital costs are high


Percutaneous Nephrolithotomy
•Percutaneous Nephrolithotomy (PNL) is effective in the treatment of
–large renal calculi
–staghorn calculi
–multiple renal stones
–lower pole renal calculi
–cystine calculi
–and calculi associated with renal outlet obstruction.
•Stone composition or moderate obesity does not hamper the efficacy of PNL.
•For renal stones > 2 cm, ESWL has been shown to be less successful, and more expensive than PNL.
•Percutaneous nephrolithotomy is very effective in rendering these patients stone free.
•Patients not rendered stone free during one percutaneous intervention can have further treatment with SWL or with a second nephroscopic session.
PCNL procedure
Percutaneous Nephrolithotomy
Sandwich Therapy
•PNL followed by ESWL is effective in the treatment of patients with multiple and or large renal stones.
•If the stone burden remains high, then a second percutaneous procedure is performed.
•This is an ideal treatment option for patients with complex stone disease, including large staghorn calculi. Sandwich therapy has proved to be equivalent to standard open nephrolithotomy with respect to preservation of renal function.
UreteroRenoscopy
•Cytoscopic-ureteroscopic procedures are best used for kidney stones located in the mid to distal ureter.
•Access is gained to the bladder through the urethra with a scope and a guide wire is placed into the affected ureter.
•Then either a rigid or flexible ureteroscope is placed into the ureter and under direct vision is guided to the level of the stone.
•Smaller stones may be grasped or entrapped in a small Dormia Stone-Catching basket and pulled from the ureter.
•Larger stones may require fragmentation with lithotripsy through the scope.
•This may be accomplished with the
–jackhammer effect of a lithoclast
–Electrohydraulic
–Ultrasonic
–laser lithotripsy.
•The risks of cystoscopic-ureteroscopic procedures include infection, bleeding, failure to remove the stone, ureteral injury.
Basketing
Open Surgery
•With the advent of ESWL, percutaneous nephrolithotomy, and cystoscopic-ureteroscopic procedures, open surgery is rarely indicated.
•It is sometimes indicated in cases with very large stone burden or cases that don’t respond to one of the other treatments.
Types of Open Surgery
•Pyelolithotomy

•Extended pyelithotomy

•Nephrolithotomy

•Partial nephrectomy

•Nephrectomy
Pyelolithotomy
•Indicated for stone in renal pelvis
•Wall dissected free and incision directly on stone
•Gall stone forceps applied
•Stone removed as a whole
•Fragments removed if present
•Pelvic incision closed by interrupted sutures
•Nephrostomy tube if sepsis
Extended pyelolithotomy
•Posterior surface of the kidney
•Plane between the renal sinus and pelvis developed
•Avoids major vessels
•Large stag horn stone can be removed

Nephrolithotomy
•Incision on renal parenchyma (Brodel’s line)
•Indicated when there are adhesions from the previous surgery
•Renal pedicle clamped to minimize bleeding
•Cooling the kidney
•Incision closed with hemostatic sutures


Partial Nephrectomy
•Lower most calyx has the stone

•Associated infection
Nephrectomy
•Indicated when Whole kidney is destroyed
•Particularly in Xanthogranulomatous Pyelonephritis
•Must be removed with care to avoid damage to adjacent structures

Laparoscopic Surgery
•Laparoscopic Pyelolithotomy

•Laparoscopic anatrophic nephrolithotomy

•Laparoscopic pyelolithotomy with pyeloplasty

•Laparoscopic assisted percutaneous nephrolithotomy in ectopic kidneys

Post-Treatment Plan
•Stone Analysis

•24-hour Urine Collection

•Recommendations
Prevention
•Recurrence of renal stones is common and therefore patients who have had a renal stone should be advised to adapt several lifestyle measures which will help to prevent or delay recurrence:
•Increase fluid intake to maintain urine output at 2-3 litres per day
•Reduced salt intake
•Reduced amount of meat and animal protein eaten
•Reduced oxalate intake (foods rich in oxalate include chocolate, rhubarb, nuts )
•Drink regular cranberry juice – increases citrate excretion and reduces oxalate and phosphate excretion
•Maintain calcium intake at normal levels ( lowering intake increases excretion of calcium oxalate).



Images in the above presentation are not included.

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