Kidney Stones

EpidemiologyEpidemiology Bladder and kidney stones detected in Egyptian mummies dating back to 4800 BC Bladder and kidney stones detected in Egyptian mummies dating back to 4800 BC Frere Jacques Beaulieu – renowned 17 th century open stone surgeon who performed 5000 open lithotomies over 30 years Frere Jacques Beaulieu – renowned 17 th century open stone surgeon who performed 5000 open lithotomies over 30 years Bladder and kidney stones detected in Egyptian mummies dating back to 4800 BC Bladder and kidney stones detected in Egyptian mummies dating back to 4800 BC Frere Jacques Beaulieu – renowned 17 th century open stone surgeon who performed 5000 open lithotomies over 30 years Frere Jacques Beaulieu – renowned 17 th century open stone surgeon who performed 5000 open lithotomies over 30 years

EpidemiologyEpidemiology Genetic Factors Genetic Factors –Rare in Native Americans, Blacks, native born Israelis –More common among Whites and Asians –25% have family history –May be result of polygenic defect with partial penetrance (Resnick, 1968) –RTA, cystinuria, several X-linked disorders Genetic Factors Genetic Factors –Rare in Native Americans, Blacks, native born Israelis –More common among Whites and Asians –25% have family history –May be result of polygenic defect with partial penetrance (Resnick, 1968) –RTA, cystinuria, several X-linked disorders

EpidemiologyEpidemiology Age and Sex Age and Sex –Peak incidence in 20’s to 40’s –3:1 male to female Higher incidence of struvite stones in females Higher incidence of struvite stones in females –Equal tendency during childhood –May have hormonal influence Age and Sex Age and Sex –Peak incidence in 20’s to 40’s –3:1 male to female Higher incidence of struvite stones in females Higher incidence of struvite stones in females –Equal tendency during childhood –May have hormonal influence

EpidemiologyEpidemiology Geography Geography –Higher prevalence in desert, and tropical climates –May be related to climate, genetic differences within regions Geography Geography –Higher prevalence in desert, and tropical climates –May be related to climate, genetic differences within regions

EpidemiologyEpidemiology Climatic and Seasonal Factors Climatic and Seasonal Factors –Higher incidence in summer months –Peak 1-2 months after the max mean temperature (Prince and Scardino, 1960) –Increased perspiration leads to increased urine concentration –Increased sunlight exposure leads to vitamin D, and increased urinary calcium excretion (Parry and Lister, 1975) Climatic and Seasonal Factors Climatic and Seasonal Factors –Higher incidence in summer months –Peak 1-2 months after the max mean temperature (Prince and Scardino, 1960) –Increased perspiration leads to increased urine concentration –Increased sunlight exposure leads to vitamin D, and increased urinary calcium excretion (Parry and Lister, 1975)

EpidemiologyEpidemiology Water Intake Water Intake –Water intake versus water lost through perspiration and respiration –Mineral content of water consumed –Dilutes and decreases transit time of solutes Occupation Occupation –Stone disease more likely in sedentary individuals, increased bone resorption –Risk increased in more affluent individuals Water Intake Water Intake –Water intake versus water lost through perspiration and respiration –Mineral content of water consumed –Dilutes and decreases transit time of solutes Occupation Occupation –Stone disease more likely in sedentary individuals, increased bone resorption –Risk increased in more affluent individuals

Types of Stones Calcium Calcium Uric Acid Uric Acid Struvite – Magnesium Ammonium Phosphate Struvite – Magnesium Ammonium Phosphate Cystine Cystine Others Others –Dihydroxyadenine –Xanthine –Silicate – antacid abusers –Matrix – urease-splitting organisms –Ammonium Acid Urate –Triamterene –Indinavir Calcium Calcium Uric Acid Uric Acid Struvite – Magnesium Ammonium Phosphate Struvite – Magnesium Ammonium Phosphate Cystine Cystine Others Others –Dihydroxyadenine –Xanthine –Silicate – antacid abusers –Matrix – urease-splitting organisms –Ammonium Acid Urate –Triamterene –Indinavir

Clinical Presentation 4 points of obstruction 4 points of obstruction –Impacted in calyx –Ureteropelvic junction –Pelvic brim –Ureterovesical junction 4 points of obstruction 4 points of obstruction –Impacted in calyx –Ureteropelvic junction –Pelvic brim –Ureterovesical junction

Clinical Presentation Renal or ureteral colic Renal or ureteral colic –Acute onset –Usually begins in flank, courses laterally around abdomen and radiates to the groin or genital region –Patients find it impossible to find comfortable position –Often nausea, emesis, ileus, diarrhea Renal or ureteral colic Renal or ureteral colic –Acute onset –Usually begins in flank, courses laterally around abdomen and radiates to the groin or genital region –Patients find it impossible to find comfortable position –Often nausea, emesis, ileus, diarrhea

Clinical Presentation Urinalysis Urinalysis –Microscopic or gross hematuria 15% without hematuria (Press and Smith, 1995) 15% without hematuria (Press and Smith, 1995) –Moderate LE / pyuria –May have urinary crystals Calcium oxalate crystals may be found if urine allowed to sit Calcium oxalate crystals may be found if urine allowed to sit Urinalysis Urinalysis –Microscopic or gross hematuria 15% without hematuria (Press and Smith, 1995) 15% without hematuria (Press and Smith, 1995) –Moderate LE / pyuria –May have urinary crystals Calcium oxalate crystals may be found if urine allowed to sit Calcium oxalate crystals may be found if urine allowed to sit

Radiographic Evaluation Plain abdominal radiograph (KUB) Plain abdominal radiograph (KUB) –90% radio-opaque Uric acid, indinavir, triamterene and matrix radiolucent Uric acid, indinavir, triamterene and matrix radiolucent Cystine, struvite less radiodense Cystine, struvite less radiodense Sensitivity 45-59% Sensitivity 45-59% Specificity 71-77% Specificity 71-77% Can be useful to guide treatment (i.e. offer ESWL) Can be useful to guide treatment (i.e. offer ESWL) Plain abdominal radiograph (KUB) Plain abdominal radiograph (KUB) –90% radio-opaque Uric acid, indinavir, triamterene and matrix radiolucent Uric acid, indinavir, triamterene and matrix radiolucent Cystine, struvite less radiodense Cystine, struvite less radiodense Sensitivity 45-59% Sensitivity 45-59% Specificity 71-77% Specificity 71-77% Can be useful to guide treatment (i.e. offer ESWL) Can be useful to guide treatment (i.e. offer ESWL)

Radiographic Evaluation Intravenous Pyelogram (IVP) Intravenous Pyelogram (IVP) –Previously the study of choice –Allows determination of obstruction, relative function –More time consuming –More invasive –Sensitivity 64-87% –Specificity 92-94% Intravenous Pyelogram (IVP) Intravenous Pyelogram (IVP) –Previously the study of choice –Allows determination of obstruction, relative function –More time consuming –More invasive –Sensitivity 64-87% –Specificity 92-94%

Radiographic Evaluation CT scan (non-contrast) CT scan (non-contrast) –Decreased time / Cost effective –No need for IV access or IV contrast –Sensitivity % –Specificity 92-94% –Does not give definitive information regarding function, obstruction –Secondary signs of obstruction Hydroureter, perinephric stranding, hydronephrosis Hydroureter, perinephric stranding, hydronephrosis CT scan (non-contrast) CT scan (non-contrast) –Decreased time / Cost effective –No need for IV access or IV contrast –Sensitivity % –Specificity 92-94% –Does not give definitive information regarding function, obstruction –Secondary signs of obstruction Hydroureter, perinephric stranding, hydronephrosis Hydroureter, perinephric stranding, hydronephrosis

Radiographic Evaluation Ultrasound – Ultrasound – can demonstrate hyperechoic focus with posterior shadowing c/w a stone can demonstrate hyperechoic focus with posterior shadowing c/w a stone Overall, not a very good imaging modality for stones. Overall, not a very good imaging modality for stones. MRI MRI Also a poor imaging modality for stones. Also a poor imaging modality for stones. Ultrasound – Ultrasound – can demonstrate hyperechoic focus with posterior shadowing c/w a stone can demonstrate hyperechoic focus with posterior shadowing c/w a stone Overall, not a very good imaging modality for stones. Overall, not a very good imaging modality for stones. MRI MRI Also a poor imaging modality for stones. Also a poor imaging modality for stones.

ManagementManagement Hospital admission required if… Hospital admission required if… –Severe Pain, N/V not controlled by medications –Bilateral obstruction, anuria, or ureteral stone with a solitary kidney –Signs of obstruction & UTI/sepsis from stone l Elevated WBC, fevers, clinical pyelonephritis Obstructing ureteral stones > 6 mm are less likely to pass, may require intervention Obstructing ureteral stones > 6 mm are less likely to pass, may require intervention stent placement vs. surgical removal stent placement vs. surgical removal Hospital admission required if… Hospital admission required if… –Severe Pain, N/V not controlled by medications –Bilateral obstruction, anuria, or ureteral stone with a solitary kidney –Signs of obstruction & UTI/sepsis from stone l Elevated WBC, fevers, clinical pyelonephritis Obstructing ureteral stones > 6 mm are less likely to pass, may require intervention Obstructing ureteral stones > 6 mm are less likely to pass, may require intervention stent placement vs. surgical removal stent placement vs. surgical removal

ManagementManagement Adequate Fluids / Hydration Adequate Fluids / Hydration –Increased diuresis may reduce rate of ureteral peristalsis and inhibit stone passage? Anti-inflammatory agents Anti-inflammatory agents –OK if creatinine is normal –Patients who received Toradol versus Demerol left hospital earlier, better pain control (Larkin, 1999) Narcotics: Morphine / Dilaudid Narcotics: Morphine / Dilaudid Flomax / Uroxatral to help pass the stone Flomax / Uroxatral to help pass the stone Only about 10% of patients require admission Only about 10% of patients require admission Adequate Fluids / Hydration Adequate Fluids / Hydration –Increased diuresis may reduce rate of ureteral peristalsis and inhibit stone passage? Anti-inflammatory agents Anti-inflammatory agents –OK if creatinine is normal –Patients who received Toradol versus Demerol left hospital earlier, better pain control (Larkin, 1999) Narcotics: Morphine / Dilaudid Narcotics: Morphine / Dilaudid Flomax / Uroxatral to help pass the stone Flomax / Uroxatral to help pass the stone Only about 10% of patients require admission Only about 10% of patients require admission

Stone Prevention: Dietary Stone Prevention: Dietary l Calcium Oxylate: –Most common type of stone ( About 80%) –Benefit from avoiding foods that are high in oxylate (low oxylate diet) l draft beer, certain juices and berries, certain green leafy vegetables, coffee, tea, peanut butter, chocolate, certain nuts l Avoid high doses of Vit. C ( > 500 mg) or D l Vit C converted to oxylate and can increase urinary oxylate l Calcium Oxylate: –Most common type of stone ( About 80%) –Benefit from avoiding foods that are high in oxylate (low oxylate diet) l draft beer, certain juices and berries, certain green leafy vegetables, coffee, tea, peanut butter, chocolate, certain nuts l Avoid high doses of Vit. C ( > 500 mg) or D l Vit C converted to oxylate and can increase urinary oxylate

Dietary Counseling: Calcium l Diet should contain adequate calcium –Moderate Ca intake, normal Ca diet ( mg/day) –Prevents calcium oxylate stones with lower GI oxylate absorption. l Don’t avoid calcium l Although certain kinds of stones can be caused by excessive calcium, overall lower incidence of stones in people who have adequate, but not excessive amounts of calcium compared to too little calcium in the diet l Diet should contain adequate calcium –Moderate Ca intake, normal Ca diet ( mg/day) –Prevents calcium oxylate stones with lower GI oxylate absorption. l Don’t avoid calcium l Although certain kinds of stones can be caused by excessive calcium, overall lower incidence of stones in people who have adequate, but not excessive amounts of calcium compared to too little calcium in the diet

Dietary Counseling l Fluid consumption: –adequate to produce > 2L daily urine output –To accomplish this, one must drink >2L l some fluid is lost with breathing, sweating and other normal body functions –Supplementing the diet with lemonade l helpful since it contains citrate which can dissolve some crystals that form stones. l Fluid consumption: –adequate to produce > 2L daily urine output –To accomplish this, one must drink >2L l some fluid is lost with breathing, sweating and other normal body functions –Supplementing the diet with lemonade l helpful since it contains citrate which can dissolve some crystals that form stones.

Dietary Counseling l Excessive protein (high purine diet) –should be avoided, especially red meats –High protein (Atkins diet) leads to a chronic acidosis increasing stone rate l Low Sodium Diet –Also recommended, generally <2g daily, with avoidance table salt, canned foods, processed foods, or things such as Chinese food that may be high is sodium. l Excessive protein (high purine diet) –should be avoided, especially red meats –High protein (Atkins diet) leads to a chronic acidosis increasing stone rate l Low Sodium Diet –Also recommended, generally <2g daily, with avoidance table salt, canned foods, processed foods, or things such as Chinese food that may be high is sodium.

ObesityObesity Higher rates of kidney stones in obese or overweight (Multifactorial) Higher rates of kidney stones in obese or overweight (Multifactorial) Sedentary lifestyle Sedentary lifestyle Dietary: Purine Gluttony, excessive Na Dietary: Purine Gluttony, excessive Na More difficult to intervene surgically More difficult to intervene surgically ESWL or PCNL ESWL or PCNL Recommend a balanced approach with diet, weight loss and exercise Recommend a balanced approach with diet, weight loss and exercise Higher rates of kidney stones in obese or overweight (Multifactorial) Higher rates of kidney stones in obese or overweight (Multifactorial) Sedentary lifestyle Sedentary lifestyle Dietary: Purine Gluttony, excessive Na Dietary: Purine Gluttony, excessive Na More difficult to intervene surgically More difficult to intervene surgically ESWL or PCNL ESWL or PCNL Recommend a balanced approach with diet, weight loss and exercise Recommend a balanced approach with diet, weight loss and exercise

Counseling Continued l Initial stone episode: –Overall, with no treatment or dietary changes, there is about a 50% chance of forming another stone within 5 years. –If another stone episode does occur despite dietary measures, I recommend a full metabolic work-up to include blood tests and a urorisk panel. l CA, Mg, Phos, Uric Acid, Urorisk. l Initial stone episode: –Overall, with no treatment or dietary changes, there is about a 50% chance of forming another stone within 5 years. –If another stone episode does occur despite dietary measures, I recommend a full metabolic work-up to include blood tests and a urorisk panel. l CA, Mg, Phos, Uric Acid, Urorisk.

Surgical Intervention l ESWL –Radiodense stones <2 cm in good location l Ureteroscopy/Stone removal –Renal/Ureteral stones <2 cm l PCNL –Large Renal or proximal ureteral stones, staghorn calculi l Open/Laparoscopic stone removal (rare) l ESWL –Radiodense stones <2 cm in good location l Ureteroscopy/Stone removal –Renal/Ureteral stones <2 cm l PCNL –Large Renal or proximal ureteral stones, staghorn calculi l Open/Laparoscopic stone removal (rare)

Questions?