Kidney Stones

Kidney Stones
Kidney Stones

Urinary stone disease (also known as renal stone disease, kidney stone disease, renal calculus disease, Nephrolithiasis, and ureterolithiasis) while found throughout the United States is most commonly found in the “stone belt.” Kidney stones will affect about 1 in 1,000 people. The “stone belt” consists mostly of the southern USA. Kidney stone disease is due to the combination of influences that include diet, heredity, dehydration, and occasionally medication.

Types of Urinary Stones

The most common stones are calcium stones. Calcium stones make up about 70-80% of all kidney stones; however, most people are unaware of the different types of calcium urinary stones that exist. For many years, these were referred to by their mineral or geologic names. These are predominately calcium oxalate dihydrate or weddellite (CaC2O4·2H2O) and calcium oxalate monohydrate or whewellite (CaC2O4·H2O). Others may contain calcium phosphate also known as hydroxyapatite (Ca10(PO4)6(OH)2) or Brushite CaHPO4·2H2O.

Kidney Stones made of Calcium Oxalate Dihydrate
Calcium Oxalate Dihydrate Stones

Calcium oxalate dihydrate stones are typically very crystalline in form. Crystalline stones are typically very spiked or rough. If you’ve ever heard anyone refer to their Kidney Stone as a sandspur or cocklebur then they were most likely referring to a calcium oxalate dihydrate stone.

Kidney Stones Made of Calcium Oxalate
Calcium Oxalate Stones

Calcium oxalate monohydrate stones on the other hand are usually knobby in shape and have few if any spiked crystals on their surface. The two types of calcium oxalate vary greatly in hardness as well as appearance. The best analogy is that of carbon. While both coal and diamonds are carbon, they exhibit very different chemical and physical properties. Like diamonds, the monohydrate forms are very dense and hard. This hardness must be taken into consideration in choosing a treatment. Calcium dihydrate is much less dense, and the crystalline nature makes them harder to pass but easier to break with Extracorporeal Shock Wave Lithotripsy or ESWL and lasers.

Uric Acid Stone
Uric Acid Stone
Uric Acid Stone

Uric Acid stone disease is much less common than calcium oxalate stone formation. Uric acid stones make up only 5-10% of all stones. Uric acid causes two different distinct medical conditions. One is stone formation of radiolucent stones. The other condition is gout. Gout is a type of arthritis caused by the crystallization of uric acid crystals in joints. The most commonly affected joints are the big toe and thumb joints. Uric acid stones do not show up on routine radiographs or x-rays such as KUB (Kidney-Ureter-Bladder film) due to their low density. These are characterized to be radiolucent stones. They do show up on CT scan as low density stones in the 400-600 Hounsfield unit range. While they are difficult to localize for ESWL using fluoroscopy, they are very fragile, and when treated, they break very well into multiple small pieces. Pure uric acid stones are usually orange colored stones. Uric acid can also be the nidus or seed crystal that allows calcium stones to form. Once the seed crystal of uric acid forms, calcium is then deposited around this initial uric acid crystal.
Struvite stone disease is most commonly associated with infection within the urinary tract. Struvite stones make up about 10% of all stones. The organisms most likely to cause these stones are urea splitting organisms. As these organisms (germs or bacteria) break down the urea in the urine, the pH of the urine increases from a baseline of pH 5 to a pH of 7, which leads to the precipitation of magnesium ammonium phosphate crystals. The most common bacteria are Proteus mirabilis, Pseudomonas Aeruginosa, Providencia Stuarti, Klebsiella Peumonia, Staphylococcus and Mycoplasma , and Serratia marcescens

Pain From Stones

Passage of a kidney stone or renal calculus is often rated as one of the top 2 pains in humans, which are childbirth and passage of a kidney stone. Women routinely compare passage to labor pains. They often report that labor pains are less intense. The pain is caused by urinary obstruction, not the existence of the stone in the kidney.
Stone disease will affect about 6-9% of all men and until recently 3-4% of women. Recent studies show the gap, between men and women with stones, to be narrowing. The ratio of men to women has changed due to an increased number of stones in women. It has long been noted that the time of first stone formation was after age 18 years. Recently, studies have shown an increase in stones in children as young as 8-10 years old.

Symptoms of Kidney Stones

Symptoms of stone passage include “flank pain”. The flank is the region of your body on your back protected by the last 2 ribs. There may be radiation of the pain around to the lower abdomen on the affected side. Patients frequently experience nausea and occasionally vomiting. As the stone passes out of the kidney into the upper ureter, men may experience testicular pain, and women may have a similar pain in the vagina or groin area. If the stone is very low in the ureter, near the bladder, then there will likely be an onset of frequent urination that can be mistaken for a urinary infection. Bladder infection, cystitis, and UTI are alternate terms for urinary infections. Men may mistake the same symptoms for prostatitis.

Deciding on a Treatment for Kidney Stones

The primary treatment of stones is based on the size and location of the stone. Stones are usually divided, by size, into groups of 1- 4 millimeters (mm), 5-10mm, and stones greater than 10mm. A 6mm stone is about ¼ inch in size. A 12 mm stone is ½ inch in size. There are 25.4 millimeters in one inch. Most stones less than 4 mm will pass and not require surgery. The average time to passage ranges from 3-6 weeks without medical intervention. This can be lessened to as little as 5-10 days with expulsive therapy using alpha blocking medications (Tamsulosin or Flomax, Cardura or Doxazosin, or Hytrin or Terazosin). The alpha blocking medications were first used in medicine as a treatment for hypertension or high blood pressure. These medications lead to dilatation of the ureter and more rapid passage of the stone. Calcium channel blockers such as Procardia (Nifedipine) and steroids such as Prednisone and Methylprednisolone have been used as well.

Surgical Indications for Kidney Stones

Indications for surgical intervention are, having a stone too large to pass, infection behind the stone, intractable pain or vomiting, or complete obstruction of the kidney leading to possible permanent kidney damage. Most of the time, it is acceptable to try to pass the stone if pain and nausea can be controlled and if there is no sign of impending kidney damage.

Risk of Recurrence of Stone Formation

After formation of a stone, there is a 14% risk of having another stone within a year, a 35% risk in the next 2 years, and up to a 52% risk of recurrence at 10 years. This rate of stone recurrence applies if nothing is done to change the patient’s risk. Up to 80-90% of people with a history of stones can modify their risk of recurrent stone formation. One can decrease one’s recurrence rate by change of diet, state of hydration, or by the addition of medications.

Hydration for Prevention

Most people with stones do not drink enough fluids, or what they do drink is high in salt or caffeine. Fluid loss through sweating can also lead to relative dehydration. The goal is to increase your fluid consumption so that there is a 2-liter (2,000-milliliter) or about 2 quarts of output of urine in each 24-hour day. Caffeine is known to be a diuretic and increases urine output. Caffeine also increases the amount of calcium excreted into that urine. This increased calcium excretion leads to more calcium in the urine than can remain in a dissolved form; therefore, crystals begin to form. This initial crystal formation is the beginning of stone formation. The best fluids for stone prevention are lemonade and orange juice. Both juices increase the urinary level of citrate. Citrate has long been known to decrease stone formation. While cranberry juice is widely misused for bladder infections, it can cause stone disease and is not recommended. Water of course is cheap and widely available. In most studies, there appears to be no benefit to bottled water over tap water. It is rare for tap water to contain enough calcium to cause stone formation.

Inheritance of Kidney Stones

Stones commonly occur in families. Most of the time, this history is easily obtainable. Some of your family may have already had a metabolic evaluation, such as a 24-hour urine collection or stone analysis. This information may help other family members as families often make the same type(s) of stones.

Dietary Causes of Kidney Stones

Multiple foods, in excess, have been found to cause stone disease. A partial list is available below.

  1. Oxalate containing foods.
    Oxalate is half of a calcium oxalate stone. Foods increasing urinary oxalate include: chocolate; nuts and nut products; vegetables such as grits, okra, spinach (most dark leafy green vegetables); most berries; draft beer; soy protein; and tea.
  2. Sodium containing foods.
    Salt or sodium increases the stone formation. Stone formation risk rises as the salt intake rises. Salt, sodium chloride, should be limited to 2,000mg =2grams of sodium per day. Most Americans consume between 12-15 grams per day.
  3. Calcium containing foods and medications.
    Calcium should be eaten in moderation as both very high and very low calcium diets can cause stones. Calcium rich foods include dairy products such as milk, cheese, yogurt, and ice cream. Calcium supplements such as Citracal (calcium citrate), TUMS, and Rolaids (calcium carbonate) increase urine levels of calcium. Spinach is high in calcium and usually increases urine levels of calcium. While more expensive, Citracal (calcium citrate) is the best form of calcium supplement in people with a history of stones needing supplements. Your calcium supplement should include Vitamin D to promote deposition of that calcium in the bones. Citracal, not only supplements your calcium, but the citrate tries to prevent stone formation from any calcium excreted in the urine. While milk substitutes such as soy milk and almond milk have less naturally occurring calcium, they are fortified with calcium and often contain more calcium per serving than cow’s milk contains. Drinking low fat milk does not lower the calcium content.
  4. Protein containing foods.
    Protein intake increases the risk of stones. Protein is found in all forms of meat (beef, pork, chicken, and fish) and not just red meat as most patients think. Protein supplements for body builders and the elderly may also lead to stone formation. The Atkins Diet popularized a low carbohydrate, high protein diet. People on this diet noted an increase in stone formation. Protein should be limited to a 4-ounce portion per meal. This portion of meat is about the size of a deck of cards.
  5. Caffeine containing foods and drinks.
    Caffeine ingested in any form increases stone formation. This includes coffee, tea, chocolate, energy drinks, caffeine tablets, and soft drinks. Decaffeinated soft drinks contain no caffeine. This is not true of coffee. There is no US government standard for low caffeine. I once read that Starbucks’ decaffeinated coffee still has more caffeine per serving than most other brands of regular coffee contains.

If you have been advised to monitor Oxalate intake with your meals, click here for a 2-page diet plan that lets you know which foods are Little or No Oxalate, Moderate Oxalate, or High Oxalate.

· Beverages· Seafood· Bread / Starch· Oils
· Milk· Vegetables· Cakes / Snacks 
· Meat / Nuts / Protein· Fruits· Ingredients 

Low Oxalate Foods

Mg

 

Medium Oxalate Foods

Mg

High Oxalate Foods

Mg

Beverages  Beverages  Beverages 
< 2mg Per Serving  2-10mg Per Serving  > 10mg Per Serving 
Coffee, Decaf1mg / 8oz Beer, Light3mg / can Hot Chocolate65mg / 8oz
Coffee, Decaf2mg / 8oz Beer, Reg4mg / can Ovaltine / Beverage Mixes35mg / 1oz / 30ml / 2Tbsp
Coke / Pepsi 12oz per day0mg / 8oz Brewed Coffee2-10mg / 3.5oz Rice Milk13mg / 8oz
Gatorade but has high salt0mg / 8oz Green Tea2-10mg / 3.5oz Rose Hip Tea10-50mg / 3.5oz
Ginger Ale0-2mg / 3.5oz Lemon Juice / Bottled4mg / 8oz Soy Milk20mg / 8oz
Koolaid0mg / 8oz Liquor0mg / 1oz Stevia Sweetner42mg / 1 packet
Root Beer0-2mg / 3.5oz Milk Chocolate Candies5mg / 1oz Tea, Black / 2 min Infusion55mg
Tea, Fennel0-2mg / 3.5oz Wine, Red1mg / 4oz Tea, Black / 4 min Infusion72mg
Tea, Lemon Balm0-2mg / 3.5oz Wine, White0mg / 4oz Tea, Black / 6 min Infusion78mg
Tea, Oolong0-2mg / 3.5oz      
Tea, Red Raspberry0-2mg / 3.5oz      
Tea, Stinging Nettle0-2mg / 3.5oz      
        
Milk  Milk  Milk 
< 2mg Per Serving  2-10mg Per Serving  > 10mg Per Serving 
Butter0mg / 1 pat Chocolate Milk7mg / 8oz   
Buttermilk1mg / 8oz      
Cheese / American, Cheddar, Cottage, Mozzarella0-1mg / 3.5oz      
Coffee Creamer0mg / 15cc      
Cream0mg / 1tsp / 15ml      
Cream Cheese0mg / 1oz      
Cream Sauce3mg / 8oz      
Cream Substitute0mg / 1tsp / 15ml      
Low Fat 2% Milk, 2 Cups / 8oz per Cup1mg / 8oz      
Nondairy Cramer0mg / 15cc      
Powdered Mild3mg / 8oz      
Skim Milk 1%1mg / 8oz      
Sour Cream0mg / 15cc      
Vanilla Ice Cream / Light / Nonfat0mg / 15cc      
Whey Fluid, Sweet1mg / 8oz      
Whey, Sweet Dried0mg / 1tsp / 15ml      
Whipped Cream0mg / 1oz      
Whipped Topping0mg / 1oz      
Yogurt / Frozen / Nonfat / Low Fat1mg / 8oz      
Yogurt / Plain2mg / 8oz      
        
Meat / Nuts / Protein  Meat / Nuts / Protein  Meat / Nuts / Protein 
< 2mg Per Serving  2-10mg Per Serving  > 10mg Per Serving 
Antelope0mg / 3oz Fish Sticks3mg / 2 sticks Almonds122mg / oz
Bacon0mg / 2 slices Tuna Salad6mg / 8oz Candies with Nuts38mg / 2oz
Beef, Ground 0mg / 3oz    Cashews49mg / 1oz
Bologna0mg / slice    Hazelnut>50mg / 3.5oz
Buffalo0mg / 3oz    Liver10-50mg / 3.5oz serving
Chicken0mg / 3oz    Macadamia Nuts21mg / 3.5oz
Chicken Dog1mg / dog    Mixed Nuts39mg / 1oz
Chicken Liver0mg / 3oz    Peanuts27mg / 1oz
Chicken Nuggets3mg / 6 nuggets    Pecans10mg / 1oz
Egg Beaters0mg / 4oz    Pistachios14mg / 1oz
Eggs0 / 1 medium    Pumpkin Seeds17mg / 8oz
Goat0mg / 3oz    Sesame Seeds>50mg / 3.5oz
Ham0mg / 3oz    Soy Burger12mg / 3.5oz
Hot Dog1mg / 1 dog    Soy Nuts392mg / 1oz
Lamb, Lean0mg / 3.5oz    Soy Yogurt113mg / 8oz
Lean Hamburger 75%0mg / 3oz    Sunflower Seeds12mg / 8oz
Lean Hamburger 85%0mg / 3oz    Tofu13mg / 3.5oz
Lean Hamburger 90%1mg / 3oz    Trail Mix15mg / oz
Liver0mg / 3oz    Veggie Burger24mg / 1 patty
Meatballs2mg / 2 balls    Walnuts31mg / .oz
Moose0mg / 3oz      
Pork0mg / 3oz      
Turkey Dogs3mg / 1 dog      
Turkey Dogs0mg / 3oz      
Wild Game0mg / 3oz      
        
Seafood  Seafood  Seafood 
< 2mg Per Serving  2-10mg Per Serving  2-10mg Per Serving 
Blue Fish1mg / 3oz      
Clams, Raw0mg / 3oz      
Cod, Pacific0mg / 3oz      
Flounder0mg / 3oz      
Haddock0mg / 3oz      
Halibut0mg / 3oz      
Herring1mg / 3oz      
King Crab0mg / 3oz      
Mackerel0mg / 3oz      
Oysters0mg / 3oz      
Pollock0mg / 3oz      
Salmon0mg / 3oz      
Sardines0mg / 3oz      
Shrimp0mg / 3oz      
Swordfish0mg / 3oz      
Tuna in Oil or Water0mg / 3oz      
Whiting0mg / 3oz      
        
Vegetables  Vegetables  Vegetables 
< 2mg Per Serving  2-10mg Per Serving  > 10mg Per Serving 
Alfalfa Sprouts0mg / 4oz Beans, Mung8mg / 4oz Bamboo Shoots35mg / 4oz
Bell Pepper, Red1mg / 3.5oz Artichokes5mg / 1 small Beans, Fava20mg / 4oz
Broccoli, Raw3mg / 3.5oz Asparagus6mg / 4 spears Beans, Navy76mg / 4oz
Brussel Sprouts0-2mg / 3.5oz Beans, Baked, Canned8mg / 3.5oz Beans, Red Kidney15mg / 4oz
Cabbage1mg / 8oz Broccoli6mg / 4oz Beans, Refried16mg / 4oz
Cauliflower1mg / 4oz Carrots, Cooked7mg / 4oz sliced Beet Greens610mg / 3.5oz
Chinese Cabbage1mg / 8oz Corn5mg / 3.5oz Beets675 / 3.5oz
Chives0mg / 1tsp / 5cc Cucumber  Brussel Sprouts17mg / 4oz
Corn1mg / 4oz Ginger2-10mg / 3.5oz Carrots, Raw15mg / 1 / 2 lg carrot
Cucumber1mg / 1 / 4 cucumber Lima Beans  Celery20mg / 3.5oz
Cucumber0-2mg / 3.5oz Linseed2-10mg / 3.5oz Collards74mg / 3.5oz
Endive0mg / 4oz Mushrooms2-10mg / 3.5oz Dandelion Greens24mg3.5 / oz
Fennel Leaves0-2mg / 3.5oz Mustard Greens4mg / cup chopped Eggplant18mg / 3.5oz
Green Chives0-2mg / 3.5oz Peppers, Chili, Hot5mg / 4oz Escarole31mg / 3.5oz
Iceberg Lettuce0mg / 8oz Radish9mg / 3.5oz Green Peppers16mg / 3.5oz
Kale2mg / 8oz Red Cabbage2-10mg / 3.5oz Kale13mg / 3.5oz
Kohlrabi0-2mg / 3.5oz String Beans / Green Beans15mg / 4oz Leeks89mg / 3.5oz
Mushrooms0mg / 1 mushroom Thyme2-10mg / 3.5oz Lentils>50mg / 3.5oz
Onions0mg / 1 small Tomato 1 Medium7mg Okra57mg / 4oz
Peas1mg / 4oz Yellow Squash4mg / 4oz Olives18mg / 10 pieces
Pickles0mg / 1 pickle    Olives, Black18mg / 3.5oz
Radishes0mg / 10 count    Parsley100mg / 3.5oz / 100gram
Romaine Lettuce0mg / 8oz    Parsnips15mg / 4oz
Sauerkraut0mg / 4oz    Peas, Snow30mg / 3.5oz
Scallions0mg    Peas, Sugar Snap 60mg / 3.5oz
Squash / Acorn0mg / 4oz    Poke Greens>50mg / 3.5oz
Water Chestnuts0mg, 4 chestnuts    Rhubarb541mg / 4oz
Zucchini1mg / 4oz    Rutabagas31mg / 4oz
      Soybeans96mg / 8oz
      Spinach600mg / 3.5oz
      Spinach, Cooked755mg / 3.5oz
      Spinach, Raw750mg / 3.5oz
      Summer Squash22mg / 3.5oz
      Swiss Chard645mg / 3.5oz
      Tempeh10-50mg / 3.5oz
      Tomato Juice22mg / 3.5oz
      Tomato Juice14mg / 8oz
      Turnips30mg / 4oz
      V818mg / 8oz
      Watercress10mg / 3.5oz
     Yams40mg / 4oz
        
Fruits  Fruit  Fruits 
< 2mg Per Serving  2-10mg Per Serving  > 10mg Per Serving 
Apple Juice2mg / 6oz Apples, Green2-10mg / 3.5oz Avocado19mg / 1 fruit
Apple, Red1mg / 3.5oz Apricots2-10mg / 3.5oz Black Berries18mg / 4oz
Apples, Dried2mg / 8oz Bananas2-10mg / 3.5oz Blue Berries15mg / 4oz
Apricot Juice2mg / 8oz Cherry, Sweet2-10mg / 3.5oz Carrot Juice27mg / 8oz
Apricots0-2mg / 3.5oz Huckleberry2-10mg / 3.5oz Concord Grapes25mg / 1oz
Apricots, Dried3mg / 8oz Kumquat2-10mg / 3.5oz Cranberry Juice25mg / 4oz
Bananas3mg Mandarin Orange2-10mg / 3.5oz Currents, Red19mg / 1oz
Bilberries2-10mg / 3.5oz Peaches2-10mg / 3.5oz Currents, Red19mg / 1oz
Cantaloupe1mg / 1 / 2 melon Pears2-10mg / 3.5oz Dates24mg / date
Casaba  Pineapple Juice3mg / 8oz Dewberries10-50mg / 3.5oz
Cherries, Bing3mg / 8oz Prune Juice7mg / 8oz Elderberry>50mg / 3.5oz
Cherries, Bing Sour2-10mg / 3.5oz Prunes, Italian5.8mg / 3.5oz Figs>50mg / 3.5oz
Cherries, Canned7mg / 4oz    Figs, Dried24mg / 5 figs
Coconut2-10mg / 3.5oz    Gooseberries, Red10-50mg / 3.5oz
Cranberries, Dried1mg / 4oz    Gooseberries / Kiwi Fruit88mg / 3.5oz
Cranberry Juice Cocktail1mg / 3.5oz    Grape Juice 24mg / 4oz
Currants, Black     Grapefruit12mg / half
Figs9mg / 1 med    Lemon Peel83mg / 3.5oz
Fruit Cocktail0-1mg / 4oz    Lemonade, From Concentrate15mg / 8oz
Grape Juice1mg / 8oz    Lime Peel110mg / 3.5oz
Grapefruit Juice1mg / 8oz    marmalade10mg / 3.5oz
Grapes1mg / 8oz    Orange Peel 
Honey Dew1mg / 8oz    Oranges29mg / fruit
Lemon Wedge1mg    Pineapple, Canned24mg / 4oz
Lemonade, Diet1mg / 8oz    Pineapple, Dried30mg / 4oz
Lime3mg / half fruit    Plums, Damson10mg / 3.5oz
Mango Juice 1mg / 8oz    Prunes, Dried 
Mango1mg / fruit    Raspberries48mg / 8oz
Melons, All Types2-10mg / 3.5oz    Raspberries, Black53mg / 3.5oz
Nectarines0mg / fruit    Raspberries, Red15mg / 3.5oz
Nectarines2-10mg / 3.5oz    Rhubarb600mg / 3.5oz
Orange Juice2mg / 8oz    Star Fruit>50mg / 3.5oz
Papaya1mg / med fruit    Strawberries10mg / 3.5oz
Passion Fruit2-10mg / 3.5oz    Tamarillo10-50mg / 3.5oz
Peaches0mg / fruit    Tangerine10mg / fruit
Pear2mg / 1 fruit      
Plantain0mg / med fruit      
Plums0mg / 1 fruit      
Plums, Green and Yellow2-10mg / 3.5oz      
Raisins3mg / 4oz      
Red Current Juice2-10mg / 3.5oz      
Watermelon0-1mg / slice      
        
Bread / Starch  Bread / Starch  Bread / Starch 
< 2 mg Per Serving  2-10 mg Per Serving  > 10 mg Per Serving 
Corn Bran0mg / 8oz Bagel, Plain9mg / 1 All Purpose Flour17mg / 8oz
Corn Flakes2mg / 3.5oz Biscuit6mg / 1 Amaranth>50mg / 3.5oz
Corn Starch3mg / 4oz Corn Flour3mg / 8oz Bagel, New York40mg
Flaxseed0mg / 15cc Cornbread4mg / 1 slice Barley Flour41mg / 8oz
Flour, Barley Malt0mg / 8oz Cracker, Triscuit1mg / cracker Bread, French11mg / 3.5oz
Oat Bran, Raw0mg / 3oz Cracker, Wheat Thins1mg / cracker Bread, Pita18mg / 3.5oz
Oat Flour0mg / 8oz Crackers, Graham2mg / rectangle Bread, Pumpernickel22mg / 3.5oz
Rice, Wild0-2mg / 3.5oz  Crackers, Ritz3mg / 5crackers Bread, Rye14mg / 3.5oz
   Crackers, Saltines1mg / cracker Bread, White21mg / 3.5oz
   English Muffin, Multi Grain8mg / 1 Bread, Whole Wheat27mg / 3.5oz
   English Muffin, Wheat7mg / 1 Brown Rice24mg / 8oz
   Flour, White Corn3mg / 8oz Brown Rice Flour65mg / 8oz
   Hummus4mg / 15ml Buckwheat>50mg / 3.5oz
   Macaroni and Cheese4mg / 8oz Buckwheat Groats133mg / 8oz
   Macaroni, Boiled7mg / 3.5oz Bulgar, Cooked86mg / 8oz
   Muffin, Blueberry9mg / 1 Bun, Hot Dog11mg / 3.5oz
   Muffin, Bran5mg / 1 Cornmeal64mg / 8oz
   Muffin, Low Fat5mg / 1 Couscous15mg / 8oz
   Oat Bran Bread4mg / 1 slice English Muffin12mg
   Oatmeal Bread4mg / 1 slice French fries51mg / 4oz
   Rye Bread7mg / 1 slice French toast13mg / 2 slices
   Sponge Cake7.5 / 3.5oz Fruit Cake 12mg / 3.5oz
   Tortillas, Flour8mg / 1 Grits, Corn97mg / 8oz
   Tortillas, Corn7mg / 1 Lasagna23mg / 4oz
   Vanilla Wafer8mg / 3.5oz Millet, Cooked62mg / 8oz
   Wheat Bran Bread7mg / 1 slice Miso40mg / 8oz
   Wheat Bread5mg / 1 slice Pancakes11mg / 4 cakes
   White Bread5mg / 1 slice 

Potato Flakes, Instant

82mg / 3.5oz
   White Rice, Cooked4mg / 8oz Potato Salad17-21mg / 3oz
   Whole Oat Bread5mg / 1 slice Potato, Baked97mg / 1 medium
      Potato, Chips17mg / 1oz
      Potato, Mashed29mg / 8oz
      Potato, Sweet 28mg / 8oz
      Rice Bran281mg / 8oz
      Rice Flower, White11mg / 8oz
      Soy Flour94mg / 8oz
      Spaghetti, Cooked11mg / 8oz
      Stuffing36mg / 8oz
      Wheat Bran130mg / 3.5oz
      Wheat Flour29mg / 8oz
     Wheat Germ269mg / oz
        
Cakes / Snacks  Cakes / Snacks  Cakes / Snacks 
< 2mg Per Serving  2-10mg Per Serving  > 10mg Per Serving 
Fruit Rollup2mg / roll Cheese Puffs5mg / 3.5oz Brownies31mg / 1oz / 1 / 2 brownie
   Chocolate Pudding4mg / serving Cake, Homemade16mg / serving
   Cookie, Chocolate Chip Low Fat7mg / cookie Cake, Store Brand15mg / serving
   Custard1mg / 8oz Chocolate Chip Cookies10mg / cookie
   Fig Bars4mg / bar Cookie, Oreo 97mg / 3.5oz
   Jello1mg / 8oz Cookies, Store10mg / cookie
   Oatmeal Cookies, Homemade2mg / cookie Cracker, Wheat Thins20mg / 3.5oz
   Oatmeal Cookies, Store4mg / cookie Fudge Sauce28mg / 1oz
   Pie, Apple5mg / serving   
   Pies, Home Made5mg / serving   
   Popsicle0mg / 1   
   Popcorn5mg / 8oz   
   Pretzels, Hard, Salted5mg / oz   
   Pudding Popsicle5mg / 1   
   Rice Cake4mg / cookie   
   Rice Krispy Treat1mg / bar   
   Rice Pudding2mg / 4oz   
   Sherbet0mg / 4oz   
   Snack Cakes, Crème Filled3mg / cake   
   Tapioca0mg / 4oz   
   Tortilla Chips7mg / oz   
  Vanilla Pudding1mg / 8oz   
   Vanilla Wafer8mg / 3.5oz   
        
Ingredients  Ingredients  Ingredients 
< 2mg Per Serving  2-10mg Per Serving  > 10mg Per Serving 
Apple Butter0mg Chili Powder7mg / 1Tbs / 15ml Black Pepper 419mg / 1oz
Basil0-2mg / 1Tbs / 15ml Cream Sauce3mg / 8oz Chocolate Syrup38mg / 1oz
Brown Sugar1mg / 8oz Gravy 4mg / 8oz Cinnamon2-10mg / 3.5oz
Bullion Cube1mg / 1cube Ranch Dressing4mg / 3.5oz Cocoa Powder67mg / 4tsp / 20cc
Catsup / Ketchup0mg / 1tsp / 15ml Soy Sauce3mg / 1Tbs / 15ml Coffee Beans42mg / 3.5oz
Corn Syrup1mg / 1tsp / 15ml    Fudge Sauce28mg / 1oz
Dill0-2mg / 1Tbs / 15ml      
Garlic Powder0mg / 1tsp / 15ml      
Gelatin0mg / 1tsp / 5ml      
Honey0mg / 1tsp / 15ml      
Horseradish0mg / 15ml      
Italian Dressing0mg / 1tsp / 15ml      
Jam / Jelly1mg / 1Tbs / 15ml      
Lard0mg / 1tsp / 15ml      
Lemon Balm0-2mg / 1Tbs / 15ml      
Mayonnaise0mg / 1tsp / 15ml      
Molasses0mg / 1tsp / 15ml      
Nutmeg0-2mg / 3.5oz      
Olive Oil and Vinegar2mg / 1oz      
Oregano0-2mg / 3.5oz      
Pancake Syrup0mg / 1tsp / 15ml      
Peppermint0-2mg / 1Tbs / 15ml      
Sage0-2mg / 1Tbs / 15ml      
Salsa1mg / 1tsp / 15ml      
Savory0-2mg / 1Tbs / 15ml      
Vinegar0-2mg / 3.5oz      
White Pepper0-2mg / 1Tbs / 15ml      
Yellow Mustard1mg / 1tsp / 15ml      
        
Cereal  Cereal  Cereal 
< 2mg Per Serving  2-10mg Per Serving  > 10mg Per Serving 
Corn Pops1mg / 8oz Apple Cinnamon Cheerios5mg / 6oz 100% Bran25mg / 3oz
Cornflakes1mg / 8oz Cheerios8mg / 8oz 40% Bran36mg / 6oz
Crispix1mg / 8oz Cinnamon Toast Crunch5mg / 6oz All Bran26mg / 4oz
Fruit Loops2mg / 8oz Complete Oat Bran Flakes5mg / 6oz All Bran Extra Fiber11mg / 4oz
Frosted Flakes1mg / 6oz Corn Chex5mg / 8oz Apple Jacks12mg / 3.5oz
Fruity Pebbles2mg / 6oz Frosted Cheerios6mg / 8oz Basic 417mg / 8oz
Honey Bunches of Oats, Honey Roasted3mg / 6oz Golden Grahams9mg / 6oz Bran Flakes173mg / 3.5oz
Honey Bunches of Oats, with Almonds2mg / 6oz Healthy Choice Multi Grain Flakes7mg / 6oz Chex Multi Grain38mg / 3.5oz
Honeycomb1mg / 10oz Honey Corn Flakes3mg / 6oz Cocoa Krispies28mg / 8oz
Kix2mg / 11oz Honey Nut Cheerios7mg / 8oz Cracklin Oat Bran15mg / 6oz
Oats, Quick2mg / 3.5oz Kashi Heart to Heart8mg / 6oz Fiber One13mg / 4oz
Product 191mg / 8oz Lucky Charms5mg.8oz Frosted Cheerios20mg / 3.5oz
Trix 0mg / 8oz Oats, Instant6mg / 3.5oz Frosted Mini Wheats53mg / 3.5oz
Waffle Crisp1mg / 8oz Rice Chex4mg / 10oz Fruit ‘n’ Fiber Dates, Raisins, & Walnuts41mg / 8oz
   Rice Krispies4mg / 10oz Granola with Raisins16mg / 4oz
   Smacks3mg / 6oz Grapenuts14mg / 4oz
   Special K3mg / 3.5oz Great Grains Crunchy Pecan17mg / 6oz
   Special K, low calorie35mg / 4oz Great Grains Raisins, Dates, and Pecans17mg / 6oz
   Special K, red berry2mg / 8oz Honey Nut Cluster23mg / 8oz
   Total corn flakes5mg / 11oz Kashi GoLean14mg / 4oz
   Wheat Chex7mg / 8oz Kashi Good Friend10mg / 6oz
   Wheaties8mg / 8oz Mueslix17mg / 6oz
      Multigrain Chex36mg / 8oz
      Muslix Apple and Almond Crunch20mg / 6oz
      Nature Valley Cinnamon Raisin Granola13mg / 6oz
      Oatmeal Crisp with Almonds42mg / 8oz
      Oatmeal Raisin Crips13mg / 8oz
      Original Shredded Wheat and Bran53mg / 10oz
      Puffed Kashi13mg / 8oz
      Raisin Bran46mg / 8oz
      Raisin Bran Crunch27mg / 8oz
      Raisin Nut Bran24mg / 8oz
      Shredded Wheat100mg / 3.5oz
      Smart Start15mg / 8oz
      Spoonsize Shredded Wheat45mg / 8oz
     Total Raisin Bran31mg / 8oz
      Wheaties Raisin Bran11mg / 8oz
        
Oils       
all vegetable oils are low oxalate0-1mg      

Medications Associated With Kidney Stone Formation

The new onset of stones can occasionally be linked to medications. The most common medications are calcium supplements. Studies vary in how much calcium is safe in supplement form. These estimates range from 1,000 to 1,500mg to 2,000mg per day for the prevention of osteoporosis. I usually recommend 1,500mg Calcium citrate with Vitamin D 400-500 IU per day in patients needing supplements.

The commonly used medication Topamax (Topiramate) causes about 1-2% of patients to begin forming stones. Current uses of this medication are for seizure disorders and prevention of migraine headaches. This medication is usually associated with the new onset of metabolic acidosis. This metabolic acidosis in turn lowers urinary citrate levels.
Zonegran (Zonisamide), a medication for control of partial seizures, may also cause 1-2% of patients to begin forming stones. The mechanism is felt to be similar to Topamax by inducing metabolic acidosis.

Vitamin C was popularized by Dr. Linus Pauling, a biochemist not a medical doctor, for the prevention of colds. He recommended 2,000 mg to 5,000mg or more per day. While this has been found not to be useful in preventing colds, it does cause stones at doses above 1,000-2,000mg per day. The excess Vitamin C is converted to oxalate and excreted in the urine. This may lead to stone formation.

Tests For Kidney Stone Recurrence Preventions

  1. Stone analysis.
    Stone analysis breaks down the most common stone’s contents into percentage of the most common minerals in each stone.
  2. 24-Hour urine collection.
    A 24-hour urine collection is used to measure the chemicals in the urine to determine which of the above dietary restrictions needs to be applied to you.
  3. Parathyroid hormone measurement.
    A parathyroid hormone blood test will test for parathyroid gland over activity. Parathyroid glands are 4 button-sized glands on the surface of the thyroid. These glands regulate calcium in the blood stream and deposition of calcium in bones. If one or more is overactive, the result is breakdown of bone with an increase in urine and blood calcium levels.
  4. Blood chemistry.
    Routine serum chemistries are also evaluated to look for illnesses that may be associated with stone formation.

Medications Used for Prevention of Kidney Stones

Urocit-K and Polycitra-K (Potassium citrate) are available in tablet form and can raise urinary levels of citrate enough to decrease the risk of stone formation in many people. While some insurance companies want to substitute cheaper Sodium citrate and Potassium chloride (KCL) for this medication, these are not appropriate substitutes.

Hydrochlorothiazide (HCTZ), a common diuretic used in hypertension, at a dose starting at 25 mg per day, increases urine output while at the same time lowering the calcium content of the urine.

Pyridoxine or Vitamin B6 has been used in the past but with lesser results and has a side effect of neurotoxicity at higher doses.

Magnesium supplementation, Magnesium oxide 400mg per day, may help some patients lower their risk of repeat stone formation.

Allopurinol 300mg per day and Potassium citrate combined with a decrease in protein intake generally makes uric acid stones smaller and less frequent. Uric acid stone disease can usually be more easily controlled than calcium stone disease.

Surgery For Kidney Stones

Surgically Removed Bladder Stone
Surgically Removed Bladder Stone

If medical management fails, then surgery becomes a treatment option. The surgical procedure recommended for you depends on multiple factors including size of the stone, location within the ureter, whether the stone is infected or not, stone density, history of previous surgical results, and history of passage of previous stones.

Open Removal of Kidney Stones

Open surgical removal of ureteral and renal stones, also called ureterolithotomy and nephrolithotomy, is still rarely needed. Starting in the 1980s, newer options greatly reduced the need for this type of surgery.

Extracorporeal Shock Wave Lithotripsy of Kidney Stones

ESWL or Extracorporeal Shock Wave Lithotripsy utilizes a percussion wave generated in water to break the stone. This technology was introduced from Germany in 1985. While the initial procedure submersed the patient in a large tub of water, this machine is rarely used today. Current second and third generation machines push a small self-contained tank of water up against the patient’s side, and the stone is localized in 2 different axes with either x-ray or ultrasound. The same percussion wave technology is then used to fragment or crush the stones into small enough pieces to pass.

Stone Fragments after ESWL

Stone Fragments after ESWL
Stone Fragments after ESWL

About 80-85% of people will require only one ESWL treatment. If fragments larger than 5 mm remain after lithotripsy, a second treatment may be needed. The shock wave is not an electrical shock but is a percussion wave. Examples of percussion waves most people are familiar with include bomb blasts and depth charges. Think about a bomb blast or a high speed wind blowing out windows or a depth charge cracking the metal in a submarine.

When the lithotripter created percussion wave hits the stone, the stone absorbs the energy and pieces of the stone break off. The more crystalline dihydrate stones are easiest to break. The monohydrate stones are much harder to break. Stone densities can be measured on a CT scan in Hounsfield units. The range of stone density for kidney stones is between 400-1,400HFU. As the density of the stone approaches 1,000HFU, the stone becomes harder to break and may require 2 treatments.

Percutaneous Removal of Renal Stones

Another Surgically Removed Bladder Stone
Another Surgically Removed Bladder Stone

Percutaneous stone removal was popularized in the 1980s as a way to avoid incisional or open stone removal. Percutaneous stone removal is used for large stones within the kidney. Usually, these stone are 25 mm or greater in diameter. One inch in maximum diameter equals 25.4 millimeters. The density of the stone also influences the choice of surgery. Denser stones that do not break well with ESWL will respond to mechanical lithotrites (Gyrus, CyberWand, and Microvasive Lithoclast Ultra). These devices use ultrasound to drive a burr or use pneumatic technology to fragment the stone while suctioning out the pieces at the same time.

For this procedure, a small needle is guided through the skin into the kidney through the flank under x-ray guidance. Dilators then enlarge the opening from 2 mm to 10 mm or about 3/8 inches. This avoids the 10-12 inch incision of an open removal. A temporary, plastic sheath is inserted into the newly established access. A telescope is guided down this tract, the stone is broken, and the pieces are removed. A drainage tube or nephrostomy tube may be left in the tract in the flank. This nephrostomy tube is removed after 2-5 days. This procedure is usually used for large stones that might have previously taken multiple ESWL procedures to fragment.

Ureteroscopy for Ureteral Stone Removal

This requires the introduction of a long, thin telescope (both metal and flexible ureteroscopes are available) through the urethra into the bladder and up the ureter to the level of the stone. A quartz, holmium, laser fiber is then typically used to fragment the stone for removal or passage. A ureteral stent, a hollow plastic tube, is then temporarily inserted to prevent swelling that may close the ureter thus causing stone like pain. The ureteral stent is usually removed after 3-5 days depending on each patient’s surgical findings. Unlike metal, vascular stents, ureteral stents must be removed. If left in place for long periods, ureteral stents can encrust with stone crystals and be difficult to remove.

Conclusion

Most people will benefit from a urologic consultation even if they pass their stone. Together, you and your urologist can decide what tests and dietary changes are right for you.