More Related Content
What's hot
What's hot (20)
Similar to Renal stone disease
Similar to Renal stone disease (20)
Recently uploaded
Recently uploaded (20)
Renal stone disease
- 1. Renal stone disease Jim Ritchie
- 2. Epidemiology • Lifetime risk: • Men 12%; women 6% (2:1) • Nationwide Inpatient survey 1.3:1 (1997 – 2002) • Untreated: 30 – 40% recurrence
- 3. Risk factors • Family history -> x2 • Ethnicity oArabic o West Indian o West Asian o Latin American oEuropean o African American • Geography • Obesity • Comorbidity oHyperparathyroidism oCrohn’s oGout o RTA • Diabetes mellitus
- 4. Imaging • Renal colic • Aortic aneurysm • Non-obstructive pyelonephritis • Retroperitoneal fibrosis • KUB radiograph • Simple but low accuracy • CT scan • 1/3 not stones • Size and position (small -> more likely to spontaneously pass) • Density (calcium 600 – 1200 HU; uric acid 200 – 400 HU)
- 5. Imaging Modality Sensitivity Specificity Radiation (mSv) Cost (c.f. KUB) CT 95 98 10 10 Low-dose CT 95 97 3 10 USS 84 53 0 5 KUB 57 76 0.7 1 MRI 82 98 0 30 Complimentary tools for disease and treatment monitoring Nat Rev Urol 2016 Nov/ 13(11):654-662
- 6. Nat Rev Urol 2016 Nov/ 13(11):654-662 ACR / AUA do not advocate as first line EAU only body to do so
- 7. Initial management - analgesia • Pain due to disordered ureteric contraction associated with obstruction • Can adapt -> presentation does not exclude obstruction • NSAID • 2 – 3x more effective than opiates • Reduce ureteric contraction frequency • Unclear if useful after acute phase
- 8. Medical expulsive therapy • Need to select stones likely to benefit < 5 mm 5 – 10 mm > 10mm • Tamsulosin 400mcg / day 2 – 4 weeks • Reduced analgesic need in acute phase (reduced contraction amplitude) • Good safety profile • May consider ongoing NSAID
- 9. Upper tract drainage • Acute renal failure • Fever • Unrelieved pain
- 10. Interventional treatment KIDNEY < 5 mm 5 – 20 mm > 20 mm Surveillance (if asymptomatic) ESWL PCNL LUMBAR < 5 mm 5 – 10 mm > 10 mm MET (EWSL if failure) ESWL Uretoscopy DISTAL URETER < 10 mm > 10 mm MET and ESWL Rigid uretoscopy MET – medical expulsion therapy ESWL – extracorporeal shockwave lithotripsy PCNL – percutaneous nephrolitomy
- 11. Extracorporeal shockwave lithotripsy • Fluroscopic / USS guidance to localise stone • Shockwaves to fragment • Stone composition and hardness • Risk for steinstrasse if rapid fragmentation and expulsion • Consideration of double-J stent prior • Acute vasoconstriction -> reduction in eGFR • No independent association with long term CKD risk • Less effective in lower pole
- 12. Percutaneous nephrolithotomy • Puncture of inferior calyx • Tract dilatation • Grasp and remove • Direct USS Laser fragmentation • High infection and bleeding risk
- 13. Ureteroscopy • Rigid or flexible endoscope • Grasp / basket • Can laser • Risk of physical damage
- 14. Patient evaluation • Stone analysis if available Bloods Ca PO4 HCO3 PTH Uric acid Urine Blood pH Infection Metabolic Urine screen Serum oxalate Age < 30 FHx Multiple / bilateral Suggestive stone composition
- 16. 24 hour urine x2 • Volume >1.5L • pH 5.8 – 6.2 • Calcium < 300 mg/dL • Uric acid < 800 mg/dL • Citrate > 500 mg/dL • Oxalate < 45 mg/day • Phosphate 500 – 1500 mg/day
- 17. Incidence
- 18. Calcium stones – metabolic issues • Idiopathic • Parathyroid • High Na / Low K diet Hypercalciuria • Normally chelates calcium • Rarely seen in isolation • Renal tubular acidosis Hypocituria • Discussed later • Also increased risk for Ca stonesHyperuricosuria • End product of metabolism • Dietary intake can be broken down in small intestine Hyperoxaluria Calcium phosphate stones Calcium oxalate stones
- 19. Calcium stones - treatment RISK DIET INTERVENTION DRUG THERAPY Low urine volume > 2.5 L fluid / day High BMI Low salt diet (DASH) Hypercalciuria Salt restrict / potassium increase Moderate protein Thiazide Potassium citrate Hypocitrauria Protein moderation Lemon juice Potassium citrate Hyperoxaluria Oxalate restriction Increase calcium intake Pyridoxine (primary) Hyperuricosuria Animal protein restrict Allopurinol Low pH Animal protein restrict Alkalinisation
- 20. Uric acid stones - primary Male Genetic risk Age, obesity, DM2 Animal protein intake Purine & fructose intake Low fluid intake Insulin resistance Reduced urine volume Increased UA generation Increased acid load Reduced renal ammoniagenesis Increased renal UA excretion Low urine pH Increased UA concentration STONE
- 21. Uric acid stones – primary treatment Male Genetic risk Age, obesity, DM2 Animal protein intake Purine & fructose intake Low fluid intake Glycaemic control Reduced urine volume Increased UA generation Increased acid load Reduced renal ammoniagenesis Increased renal UA excretion Low urine pH Increased UA concentration STONE
- 22. Uric acid stones – primary treatment Male Genetic risk Age, obesity, DM2 Reduce animal protein intake Purine & fructose intake Low fluid intake Glycaemic control Reduced urine volume Increased UA generation Increased acid load Reduced renal ammoniagenesis Increased renal UA excretion Low urine pH Increased UA concentration STONE
- 23. Uric acid stones – primary treatment Male Genetic risk Age, obesity, DM2 Reduce animal protein intake Reduce purine & fructose intake Low fluid intake Glycaemic control Reduced urine volume Increased UA generation Increased acid load Reduced renal ammoniagenesis Increased renal UA excretion Low urine pH Increased UA concentration STONE
- 24. Uric acid stones – primary treatment Male Genetic risk Age, obesity, DM2 Reduce animal protein intake Reduce purine & fructose intake 2.5 – 3 L Fluid Glycaemic control Reduced urine volume Increased UA generation Increased acid load Reduced renal ammoniagenesis Increased renal UA excretion Low urine pH Increased UA concentration STONE
- 25. Uric acid stones – primary treatment Male Genetic risk Age, obesity, DM2 Reduce animal protein intake Reduce purine & fructose intake 2.5 – 3 L Fluid Glycaemic control Reduced urine volume Increased UA generation Increased acid load Reduced renal ammoniagenesis Increased renal UA excretion Urine pH >6.5 Increased UA concentration STONE
- 26. Urinary alkalinisation • Potassium citrate (40 – 60 mEq/day) • Potassium urate twice as soluble as sodium urate • Sodium bicarbonate is acceptable alternative if not available / tolerated • Can be used as an acute treatment (very amenable to ESWL) • Allopurinol not first line therapy but can be required
- 27. Uric acid stones - secondary • Chronic diarrhea -> fluid and base losses • Fluid replace and offer alkali • Myelo and lymphoproliferative disease • Standard treatment approach • Case reports of use of Rasburicase (recombinant urate oxidase) • Tubular disease (Fanconi) • Purine metabolism errors
- 28. Cystine stones • Cystinuria IS NOT cystinosis • 1% of stones • Genetic disorder • SLC3A1 / SLC7A9 • Testing not clinically routine (unless inheritance is a concern) • Inadequate tubular reabsorption of cystine in both forms • Supersaturation -> stones • Tubular crystals -> fibrosis and atrophy
- 29. Cystine stones - diagnosis • Stone analysis (urine microscopy; hexagonal crystals) • Poorly seen on KUB • Urine cystine quantification • diagnosis and monitoring • Cyanide-nitroprusside test lacks sensitivity / specificity
- 30. Cystine stones – treatment • Often resistant to ESWL -> low threshold for PCNL DIET SOLUBILITY CHELATION Reduce animal protein Reduce sodium Less methionine -> cystine prodn Less cystine excretion Alkalinisation Less cystine excretion >3 l oral fluids Lower urinary concn Tiopronin D- penicillamine
- 32. Cystine stones – treatment • Often resistant to ESWL -> low threshold for PCNL DIET SOLUBILITY CHELATION Reduce animal protein Reduce sodium Less methionine -> cystine prodn Less cystine excretion Alkalinisation Less cystine excretion >3 l oral fluids Lower urinary concn Tiopronin D- penicillamine
- 33. Cystine stones - chelation • Bind to create cysteine -> 50x more soluble • D-penicillamine • Poorly tolerated • B6 supplementation • Tiopronin • Not UK license • Import problems • Much better tolerated
Editor's Notes
- Men risk peaks age 40 – 60; women peaks in 20’s and then declines through life Treatment / lifestyle modification halves risk for repeat stone formation
- Southeast US – much greater risk than NW; Obesity interacts with gender – men 30% women 100% if BMI >30 Diabetes prospectively increases risk in women > men Lot sof other clinical consditions eg sarcoid, meduallry sponge kidney, GI issues e.g. short bowel
- Hounsffield units: Water 0; Dense bone 1000; Air -1000
- KUB better for larger stones (>5mm)
- KUB does not appear! USS complicated in the overweight; low dose CT lnot advocated by an imaging body in the overweight USS has the advantage of describing the urinary tract e.g. what are the complications of the stone EAU – european assocaition of urology AUA – american urology association ACR – American college of radiologists Diagnosis – CT Follow up USS / KUB
- Nephrostory is sledinger technique – exactly as for a line….
- Drugs - lithium reduces parathyroid sens to Ca -> increased risk Vit D Corticosteroids
- Oxalate – bowel issues; Crohns, coeliac, sprue, overgrowth, panc insufficiency; IBD
- Dietary cCa restriction drives hyperoxaluria Avoid loop diuretics
- Fundamentally, this is all about urine saturation – UA quantity and urine volume Plus other factors that influence saturation – pH is key
- Fundamentally, this is all about urine saturation – UA quantity and urine volume Plus other factors that influence saturation – pH is key
- Fundamentally, this is all about urine saturation – UA quantity and urine volume Plus other factors that influence saturation – pH is key
- Fundamentally, this is all about urine saturation – UA quantity and urine volume Plus other factors that influence saturation – pH is key
- Fundamentally, this is all about urine saturation – UA quantity and urine volume Plus other factors that influence saturation – pH is key
- Fundamentally, this is all about urine saturation – UA quantity and urine volume Plus other factors that influence saturation – pH is key
- Urine alk -> potassium citrate / bicarb Get upH > 7.5 -> double solubility of cystine. Stops need to 5L fluids If NaHCO3 needed then not as good but alk > Na restriction Captopril does not have evidence base
- Fluid needs to be spread out and monitored Always carry Wake overnight
- Urine alk -> potassium citrate / bicarb Get upH > 7.5 -> double solubility of cystine. Stops need to 5L fluids If NaHCO3 needed then not as good but alk > Na restriction Captopril does not have evidence base