Kidney Disease-1

1)Kidney Function

2)Kidney Disorders

3)Factors Affecting Function

4)Autosomal Dominant Polycystic Kidney Disease

5)Treatment

6)Summary

For many years, the Centers for Disease Control (CDC) has listed kidney disease as one of the top 10 causes of death by disease in the United States. Kidney disease also plays a significant role in hypertension and diabetes, two other diseases that are also included on the CDC's list of top ten causes of death each year. End-stage renal (kidney) disease (ESRD) is growing at a rate of 4-8% each year in the United States. Someone with advanced ESRD may require either therapeutic or regular dialysis, or both, and may eventually require a kidney transplant to save his or her life. When kidney function is reduced to 10-15% or less, dialysis is started in ESRD patients. Sometimes ESRD patients are placed on a waiting list for a kidney transplant.

According to statistics compiled by the National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK)(2001), kidney conditions such as inflammation, kidney stones, and cancer affected some 2.553 million persons; ESRD affected 424,179 people; polycystic kidney diseases affected 600,000 people; and other urinary conditions such as kidney infections, bladder infections, and cystitis affected millions more, costing billions of dollars of medical care funded by the public and by private individuals (NCHS 1999; Grantham et al. 2000; USRDS 2001).

Due to the limited scope of this protocol, we will briefly describe some of the more common kidney disorders and treatments. However, two conditions will be described in greater detail: autosomal dominant polycystic kidney disease (ADPKD) and kidney stones. ADKPD is a common human genetic disease, resulting in many cases of ESRD and eventually the need for kidney transplantation. Kidney stones affect approximately 10% of the U.S. population at some point in their lives (LaPorte et al. 1990). Unfortunately, about 60% of persons who have a kidney stone will develop another stone. In statistics reported by the NIDDK, urinary stones accounted for 1.325 million visits to physicians in 1997 (NIDDK 2001b).

Attention to overall kidney health is essential. If you have healthy kidneys, take care of them. Educate yourself about how to do this. We will provide information in the paragraphs that follow to assist you in being proactive in maintaining healthy kidneys. If you have a health condition such as diabetes or hypertension that poses a threat to your kidneys, seek a qualified medical professional to treat and control these conditions. Then carefully follow monitoring and treatment advice. Information will also be provided to assist you in supporting kidneys that have already sustained damage.


KIDNEY FUNCTION
The kidneys are bean-shaped organs that act as sophisticated filters to remove organic waste products from the blood and then excrete these waste products, along with excess salt and water, from the body through the urine. We are normally born with two kidneys located on either side of the lower back just below the rib cage. The kidneys are such incredibly well-functioning organs that only one normal, healthy kidney is required for good health. Each kidney is 4-5 inches long, weighs about 6 ounces, and contains about 1 million nephrons. Nephrons are the working units of the kidney that are responsible for waste removal (NIDDK 1998). As part of our normal aging process, kidney function diminishes as the number of functional nephrons is reduced.

The kidneys play a role in controlling the acid-base balance in the body as well as helping to control blood pressure. Another function of the kidneys is to produce hormones such as erythropoietin, which regulates the production and release of red blood cells from the bone marrow.

Each day, the kidneys filter approximately 200 quarts of blood, producing about 2 quarts of waste products and water (NIDDK 1998). These waste products and excess water pass from the kidneys through the ureters (tubes that connect the kidneys to the bladder) and into the bladder where they are briefly stored before being eliminated as liquid waste via the urine. Filtered waste products include the normal organic material from the breakdown of cells, proteins, excess food by-products, and various minerals, as well as the individual waste excretions from cells of the body. Alcohol, drugs, excess protein, minerals, and ingested toxins are also filtered by the kidneys. These toxic agents can have a dramatic, destructive effect on the health and function of the kidneys.

The rate of blood flow through the kidneys is about 20% of the total blood pumped by the heart each minute. (Anatomical Chart Company 2002®, Lippincott Williams & Wilkins)

Kidney function is often measured by using routine blood and urine tests to indicate gross problems. These tests measure creatine levels, possible blood in the urine, blood urea nitrogen (BUN), proteinuria (protein in the urine), and mineral content, including calcium, magnesium, phosphorus, sodium, potassium, oxalic acid, and other elements. If blood or urine tests indicate improper kidney function, additional testing is indicated using conventional x-rays, needle biopsy, ultrasound, a computed tomography scan (CT scan), or magnetic resonance imaging (MRI) (NORD 2002).


KIDNEY DISORDERS

1)Kidney Stones

2)Medical Intervention

3)Prevention

Kidney disease is any disorder that affects how the kidneys function. A list of all of the diseases and conditions that can affect kidney function and the possible causes are beyond the scope of this protocol. However, some of these disorders include analgesic nephropathy, chronic nephritis, diabetes, ESRD, hypertension, infection, injury, stones, lupus erythematosus, and ADPKD (NORD 2002).

Symptoms of renal disease can include frequent headaches and urination, itching, poor appetite, fatigue, burning bladder, anemia, baggy eyes, nausea and vomiting, swollen or numb hands or feet, poor concentration, darkened skin, and muscle cramps (NORD 2002).


Kidney Stones (Calculi)
Kidney stones (or calculi) are a common condition and also an incredibly painful one. It is estimated that in the United States, 10% of us will pass a kidney stone at some time in our lives. Men have more kidney stones than women, and white people are more prone to kidney stone formation than black people. The incidence of kidney stones is higher in the summer. This may be because we perspire more in the summer and our urine becomes more concentrated.

A kidney stone is a solid, rock-like type of material that has formed or is present in the kidneys, ureters, or bladder. A kidney stone is formed from mineral substances that precipitate from the urine. Kidney stones can stay in the kidney or travel down the urinary tract. Small stones are sometimes passed from the body with either a small or large degree of pain. Larger stones may lodge in the ureter, bladder, or urethra, blocking urine flow and causing extreme pain (NIDDK 1998).

Most kidney stones contain calcium combined with either oxalate or phosphate. Calcium stones are formed when extra calcium is not eliminated in the urine. Another type of kidney stone is a struvite stone. A struvite stone can form following a urinary infection. Uric acid stones form when there is too much acid in the urine. A rare type of kidney stone is made up of cystine. Evidence shows that cystine-based stones tend to run in families (the result of a genetic disease) (NIDDK 1998).

Kidney stones vary widely in size: from a grain of sand, to the size of a pearl, or to the size of a golf ball. However, most kidney stones are quite small. Kidney stones can grow to a size that is life threatening or that requires surgical removal. Some large kidney stones cannot be surgically removed because of the age of the patient or because of the danger of associated trauma to a vital organ.

Kidney stones are usually yellow or brown in color. Their structure and texture can be smooth or jagged. Another common visual characteristic is a crystalline appearance with different mineral striations appearing throughout the structure of the stone. Examination and testing of a kidney stone by a specialist in urology can determine significant information about the possible cause of the kidney stone and perhaps suggest a remedy for people who have the potential to form additional kidney stones (NIDDK 1998).

As noted earlier, kidney stones tend to run in families. They can also be associated with geographic factors as well. Therefore, people who live in tropical climates may be at greater risk for kidney stone formation because of the way the body manages water in a tropical setting. As a percentage, perspiration often becomes the prevalent method of how the body excretes water in tropical or very hot conditions, and urination may decline slightly because urine is stored longer in the urinary tract. Although it seems obvious, the fact is that most people do not drink enough water every day, and in tropical areas this is even more significant. Excessive perspiration becomes even more significant when performing hard physical labor or engaging in strenuous sports activities in very hot conditions. The body loses large amounts of water during excessive perspiration. For example, a NFL lineman can lose as much as a gallon of water or as much as 10 lbs of water weight during a 4-hour game. Therefore, sufficient water intake is both a preventive and a therapeutic measure.

The symptoms of a kidney stone attack include sudden extreme pain in the lower back, side, or groin; blood in the urine; fever and chills; vomiting; a bad odor or cloudy appearance to the urine; and a burning sensation during urination. Any of these symptoms require evaluation by a physician. Pain in the lower back, side, or groin can also be indicative that a kidney stone is moving or that there is a serious urinary tract blockage that requires immediate medical intervention. Kidney stone episodes frequently include urinary tract infections (UTIs). Recurrent, untreated UTIs can eventually cause permanent kidney damage and reduced kidney function.

Passing a kidney stone can be as simple as drinking large amounts of liquid and running up and down stairs or jumping up and down vigorously to dislodge the stone! This practice uses the basic physics of gravity to get the stone moving so that it can be passed normally. If you know you are passing a kidney stone, try to catch it in a strainer or retrieve it so it can be examined by a nephrologist or urologist (NIDDK 1998).


Medical Intervention for Kidney Stones
Many kidney stones pass from the body on their own with no medical help. However, more complex procedures are required to assist stones that cannot be passed or to remove stones that are growing larger (NIDDK 1998). Either lithotripsy or surgical removal of the stone is used when a kidney stone is firmly lodged in the ureters, bladder, or urethra. In the past, problem kidney stones represented a significant health concern because the only way to remove them was invasive surgery with a high risk of postoperative infection. It is now possible for urologists to avoid surgery except as a last resort or when there is no other alternative. Newer methods to remove kidney stones include using ureteroscopy, tunnel surgery, extracorporeal shock wave lithotripsy (ESWL), and percutaneous lithotripsy. All of these methods break the stone into smaller pieces so that the stone can be removed or passed through the urinary tract (NIDDK 1998).


Preventing Kidney Stones
Research into the prevention of recurrent kidney stones has produced many helpful dietary guidelines, nutritional protocols, and lifestyle changes that can reduce or eliminate the potential for future kidney stones. Using these effective protocols can significantly reduce the chance of recurring kidney stones after a first episode. They may also help pass a recurrent stone faster and with less difficulty.

In 1997, a research division of a healthcare provider conducted a double-blind study with a group of 64 patients who had a history of renal calculi to determine if potassium/magnesium citrate would prevent the recurrent formation of calcium oxalate kidney stones (Ettinger et al. 1997). The patients were given 42 mEq (milliequivalent) potassium, 21 mEq magnesium, and 63 mEq citrate or a placebo daily for 3 years. New renal calculi formed in 63.6% of patients receiving the placebo. However, patients receiving the potassium/magnesium citrate protocol presented with 12.9% recurrent renal calculi. Ettinger et al. (1997) concluded that "potassium/magnesium citrate effectively prevents recurrent calcium oxalate stones, and this treatment given for up to 3 years reduces risk of recurrence by 85%."

Contrary to what was considered to be "common sense" thinking in the past, two major studies have shown that calcium should not be reduced for patients with a history of kidney stones (Takei 1998; Williams 2001). It was originally postulated that patients with a history of renal calculi should limit their intake of calcium. In fact, current recommendations from the National Institutes of Health published on their Web site continue to call for calcium-restricted diets. Such dietary changes also affect the alkali and pH of the body by calling for the restriction of foods such as apples, beets, parsley, broccoli, spinach, and pineapples. However, newer findings contradict these dietary restrictions and offer scientific evidence that uncombined intestinal oxalic acid is the real culprit for calcium oxalate kidney stones (Ohgitani 2000).

Harvard researchers studied nearly 92,000 nurses over a period of 12 years to determine the relationship between calcium intake and the occurrence of renal calculi (the well-known Harvard Nurses' Health Study). The conclusion of this massive study was that those nurses who consumed diets that were higher in calcium were at lower risk for kidney stones!

The reason that this type of dietary modification reduced the chance of kidney stones was relatively simple. A high percentage of kidney stones are comprised of calcium and oxalic acid which form calcium oxalate inside the kidneys. Oxalic acid is able to pass through the intestinal wall into the blood and enter the kidneys where it has a chance to combine with calcium. Calcium oxalate, when normally combined inside the digestive tract, does not pass through the intestinal wall and into the blood, but is eliminated with other waste products. Therefore, when oxalic acid combines with dietary calcium or supplemental calcium inside the intestinal tract, oxalic acid will never reach the kidneys and therefore calcium oxalate kidney stones cannot be formed.

The Harvard Nurses' Health Study presented the following important findings: dietary calcium intake from food or supplements reduced the risk for renal calculi; calcium supplementation must be taken with food and in small dosages (< 400 mg); plant foods high in calcium, fiber, vitamins, minerals, antioxidants, and some protein were an excellent source for dietary phytochemicals.

Another study conducted in South Africa found that "mineral water containing calcium and magnesium deserves to be considered as a possible therapeutic or prophylactic agent in calcium oxalate kidney stone disease" (Rodgers 1997). A French mineral water containing calcium (202 ppm) and magnesium (36 ppm) was selected as the delivery method. Twenty subjects of each sex who had previously formed calcium oxalate renal calculi and 20 healthy volunteers of each sex participated in the study. Each subject provided 24-hour urine collection samples each day during the study. The mineral water was ingested over a 3-day period. Then the participants switched to tap water. The cycle was repeated at least twice by each subject. The male stone formers received the most benefit, showing nine risk factors that were favorably affected by the mineral water containing calcium and magnesium (Rogers 1997).

Recommendations from the National Kidney and Urologic Diseases Information Clearinghouse (1998) include a few simple things to do to avoid kidney stones:

1)Drink more water. Try to drink at least 12 full glasses of water each day. Drinking extra water helps to flush substances that form stones from the kidneys.

2)It is not necessary to eliminate coffee, tea, and colas from your diet, but limit caffeine because it can increase fluid loss. Consider drinking ginger ale, lemon-lime soda, and fruit juices.

3)Follow your physician's recommendations about dietary limitations. If you form uric acid stones, your physician will probably ask you to eat less meat because meat breaks down to form uric acid.

4)Follow your physician's recommendations about taking medicines to prevent stone formation.