Kidney Stones

www.normanforsenate.com

2011-08-26T23:37:00.003-07:00

Wee Forest Folk
Look Younger Secrets
Bob Marley Quotes
Happy Birthday Quotes
Quotes About Marilyn Monroe
Inspirational Quotes
Health Cleanse
Tips.com
Dumpster Rental Chicago
Lawyers
Essay Writing Help
Lubricants Personal
Towing Atlanta
Slimquick Reviews
Low Testosterone Treatments
Criminal Defense Lawyer
Viking Refrigerator
Essay Writing
Research Papers for Sale
Cute Quotes
Atlanta Remodeling
Wee Forest Folk
Free Flash Games
Website Ideas
Howard Miller Clocks
Life Quotes
Medicine For Younger – Lotus
Elf on the Shelf
Dr. Seuss quotes
Friendship Quotes

Baliku-Balimu.info

2011-06-10T22:51:00.001-07:00

Baliku-Balimu.info

Travel Blog tentang wisata Bali. Berisi tentang tempat-tempat menarik dan wisata Bali. Tips-tips hemat berwisata ke Bali. Wisata Badung, Denpasar, Tabanan, Gianyar, Bangli, Karangasem, Singaraja, Klungkung dan Jembrana.

Keindahan Matahari Terbit di Pantai Sanur

Pantai Manakah yang Paling Indah di Bali (Sunset Beach)

Pantai Manakah yang Paling Indah di Bali (Sunrise Beach)

Indahnya Sunset di Uluwatu

Pantai Kuta yang tetap cantik

6 Sawah Terasering "Must Visit" Saat Berwisata ke Bali

Foto - Foto Pura Ulundanu Batur

Murah dan Nyamannya Transportasi Umum di Bangkok

4 Danau yang Wajib Dikunjungi saat Anda Berwisata ke Bali

PHOTOS PLACES OF INTEREST IN BALI - BERATAN LAKE AND ULUNDANU TEMPLE

Taman Ayun, Pura yang Cantik nan Eksotis

Berburu Kesegaran di Tiga Air Terjun Desa Gitgit Buleleng, Bali

Keindahan Persawahan Jatiluwih

Air Terjun di Bali. Danau di Bali, Jalan-jalan hemat Bali, Pantai di Bali (Bali Beach), Pura di Bali (Bali Temple), Sawah Terasering di Bali (Bali Rice Terraces),

Something Blue in Bali and Indonesia

2011-05-30T11:21:00.001-07:00

Somethingblue.us

Something Blue in Bali, Indonesia and Beyond. Travel tips and interesting places in Bali, Indonesia and Beyond. Bali Beach, Indonesia Beach, southeast Asia and interesting places in the world. Enjoy all info in this site..

Spectacular Sunset at Tanah Lot, The Spectacular of Uluwatu Temple, Kuta Beach is Still Beautiful, Padang-Padang Beach Bali, Beautiful Sunrise at Sanur Beach, Bromo, Mount with very Beautiful Sunrise, Ijen, The Exotic Crater

Sitemap

2011-04-20T17:12:00.001-07:00

Atazanavir associated with significant risk of kidney stones and renal impairment

2011-04-19T17:38:00.001-07:00

Studies presented at last week’s BHIVA conference found that kidney stones were four times more common in people taking the protease inhibitor atazanavir than in people taking other drugs. However they were still relatively uncommon – about one case in 50 patients who were being investigated for possible kidney stones turned out to have them.

A parallel study found a significant association between atazanavir and signs of renal failure, though it also found associations between impairment and other protease inhibitors too.

Atazanavir and kidney stones

In the first study Neesha Rockwood and colleagues from the Chelsea and Westminster Hospital in west London did a retrospective case note review of patients attending the clinic between May 2006 and February 2010, singling out those who had had an abdominal X-ray or CT scan, a renal ultrasound scan, or an intravenous urogram (in which a contrast medium is injected and then x-rays are taken of it being excreted via the urinary system). These four procedures indicate that kidney stones are being investigated as a possible diagnosis.

She only included in this study patients who underwent one of the above investigations and were taking either the non-nucleoside drug (NNRTI) efavirenz (Sustiva, and in Atripla) or one of the protease inhibitors (PIs) atazanavir, lopinavir or darunavir (Reyataz, Kaletra, Prezista).

There have been case reports of kidney stones in patients taking atazanavir and analysis of these stones showed that they consisted of drug that has dissolved out of urine: atazanavir is less soluble in alkaline fluids, which is why it must also not be taken with antacids.

A sub-analysis excluded people with previous exposure to the PI indinavir (Crixivan), which is now hardly used because of its tendency to cause kidney stones. In all over 6,000 patients’ notes were reviewed. Of these 1206 people had taken atazanavir, 2803 efavirenz, 828 lopinavir and 818 darunavir, and 206 had previously taken indinavir.

Two per cent of patients taking atazanavir developed kidney stones, at an annual rate of 0.73% of patients per year (an annual event rate of one case per 137 patients). In contrast 0.54% of patients on the other three drugs developed kidney stones, an event rate of 0.19% or one event per 526 patients.

When patients with previous indinavir exposure were excluded, this brought the percentage of patients with kidney stones on atazanavir to 1.5%, with an annual event rate of 0.46% (one in 217 patients a year). The annual event rate in patients on the other three drugs who had not taken indinavir was 0.12% (one in 833 patients a year).

This meant that patients on atazanavir were 3.85 times as likely to get kidney stones as patients on the other drugs, and although excluding previous indinavir users brought the rates down, the relative difference remained the same.

Patients on darunavir were somewhat more likely to get kidney stones than patients on lopinavir or efavirenz (annual event rates 0.45%, 0.19% and 0.15% respectively).

Patients who had kidney stones were ten times more likely than others to have histories of chronic renal impairment and their levels of the liver waste product bilirubin (which causes jaundice, another side-effect associated with atazanavir) were on average twice as high.

Dr Rockwood said her study probably underestimated the prevalence of kidney stones in patients as some stones were transparent to X-rays and cases in patients who had transferred from other hospitals could have been missed. Atazanavir could have consequences after it was stopped: in one case, a kidney stone containing atazanavir was found in a patient who had stopped the drug 21 months previously.

Protease inhibitors and renal impairment

In a second study, this time of atazanavir’s effect on the kidneys’ ability to filter waste products, the same team found a 52% increased risk of this kind of chronic kidney disease in patients on atazanavir compared to the whole patient group. However this was lower than the risk associated with lopinavir (69% increased risk) and there was some association with darunavir use too, though this became statistically insignificant in multivariate analysis.

Chronic kidney disease was defined as an estimated glomerular filtration rate (eGFR) of less than 60 millilitres per minute per 1.72m². EGFR is based on levels of the waste product creatinine in the blood and defines the amount of blood the kidneys are able to filter.

This study assessed the rate of kidney impairment in patients prescribed the same four drugs as in the previous study. Out of 2115 patients (78% male, 60% with an undetectable viral load) prescribed these therapies, 386 (18%) developed renal impairment as defined above.

Women were over 50% more likely to develop renal failure, and older patients considerably more likely, as seen in other studies (kidney failure becomes more frequent with age). Patients taking atazanavir, darunavir or lopinavir were, respectively, 27%, 53% and 71% more likely to develop kidney failure. Other risk factors included a history of tenofovir use (68% more likely) and chronic hepatitis B infection (21% more likely).

The risk associated with current tenofovir use appeared to accumulate with time (9% raised risk for each year on tenofovir).

Viral load or CD4 count at baseline, ethnic origin and hepatitis C co-infection were not associated with kidney failure.

Patients currently taking efavirenz had a 40% reduced risk of renal impairment compared with the average patient, though this advantage disappeared if they stopped efavirenz.

In multivariate analysis, taking lopinavir was associated with a 69% higher risk of kidney impairment than taking efavirenz. Patients taknig atazanavir had a 52% higher risk of renal impairment than patients taking efavirenz.. The risk with darunavir (versus efavirenz) was raised 31% but this became statistically non-significant (i.e. the effect of other variables became more important).

There was some recovery after the protease inhibitors were withdrawn. Half the patients who reached an eGFR below 60ml/min/1.73m² had an eGFR above this figure a year after stopping. Patients who were on tenofovir had a 30% greater rate of renal recovery if they stopped this drug in addition to their protease inhibitors; however stopping tenofovir by itself was not associated with significant improvement.

Atazanavir side effects are likely to come under more scrutiny in the future as the London HIV Consortium has recently made an agreement with HIV clinicians that it will be the first PI of choice in patients who need to take this class of drugs, and some patients will be encouraged to switch to it.

There are several ways to treat kidney stones

2011-04-16T18:47:00.001-07:00

Kidney stone (also known as nephrolithiasis) is one of the most painful urologic diseases. It is the migration of stone that forms at the level of the kidney through the different structures of the urinary system (the uretere, urinary bladder and urethra).

Kidney stone disease was described by ancient civilizations (Mesopotamia, India, China, Persia, Greece and Rome). It was discovered in the pelvis of an Egyptian mummy (dated to 4800 BCE). Among the famous leaders that suffered from this disease were Napoleon Bonaparte, Napoleon III, Peter the Great, Louis XIV, George IV and former U.S. President Lyndon B. Johnson.

Clinically, during the process of migration, the stone can cause severe pain that typically starts in the flank. As the stone progresses, the pain starts to localize to the groin and the genital area, causing blood in the urine, nausea and vomiting. In most cases, the stone continues its migration and is eliminated in the urine. Many stones are formed and passed without causing symptoms. In a small percentage of patients, the stone is big in size and will block the uretere causing blockage of the urine flow compromising the kidney’s function and increasing the risk of infection of the kidney

TYPES OF STONES

There are several types of kidney stones which are categorized by the type of crystal forming the stone. The most common stones contain calcium oxalate, which can be formed without any predefined risk factors. The calcium phosphate is mainly common for patients with genetic or acquired defect in excretion of acidic materials in the urine.

Struvite stones are exclusively present in patients with recurrent urinary tract infections. Cystine stones result from an inherited condition that causes an increase in the amount of cystine (an amino acid) in the urine. Uric acid stones form only in acidic urine and cannot typically be seen by X-ray imaging.

TREATMENT

The treatment includes two parts: The acute management of the stone and the prevention of recurrence. The management during the acute kidney stone crisis is conservative and consists mainly of hydration (usually oral hydration is enough unless the patient has continuous vomiting) and pain medication (NSAIDs and/or opioids).

The need for immediate evaluation by a urologist is warranted if the patient has a fever, is not producing urine or has acute renal failure. Intervention is indicated urgently in these cases to remove the stone which is blocking the urine flow.

Patients are instructed to strain the urine in order to collect the stone and bring it to the lab for analysis. The stone size will determine the likelihood of passage. Most stones that are 4 millimeters (mm) in diameter pass spontaneously. Stones that are 10 mm in diameter are unlikely to pass.

To facilitate stone passage several medications can be used. The most common medication is tamsulosin. For large stones, patients are referred for nonurgent urology evaluation. Current therapy options for stones that fail to pass include:

*Shock wave lithotripsy, in which a doctor uses a machine to send shock waves directly to the kidney stone and break it into smaller stones that can pass in the urine.

*Ureteroscopic lithotripsy with electrohydraulic or laser probes, which utilizes specialized probes to remove or fragment the stone.

*Percutaneous nephrolithotomy, also known as tunnel surgery, in which a doctor makes a small cut into the patient’s back and makes a narrow tunnel through the skin to the stone inside the kidney. Using a special instrument that goes through the tunnel, the doctor can find the stone and remove it.

*Laparoscopic stone removal, which uses small scopes inserted through the skin to remove the stone.

Open surgical stone removal is rarely needed. The choice of therapy depends again on the size of the stone and the composition.

PREVENTION

Preventing a recurrence of kidney stones depends on the type of stones, but here are some general measures applicable for all types of kidney stones.

*Increase fluid intake. Patients should increase their fluid intake to produce at least two liters of urine per day. However, be careful about the choice of fluid. Grapefruit juice may be associated with an increased risk of stones. Patients should avoid cranberry juice and calorie-containing beverages. Coffee, tea and alcohol have a lower risk of causing stones.

*Reduce animal protein intake.

*Increase fruit and vegetable intake (high in citrate an inhibitor of stone formation).

*Limit dietary oxalate intake, such as spinach, rhubarb, peanuts, cashews and almonds.

*Limit salt, sucrose, fructose, high dose vitamin C intake.

*Weight control may be helpful in preventing stone recurrence.

*Drug therapy is indicated if the stones are recurrent. Therapy is dependant on the type of stone.

Bali Best Travel

2011-04-16T01:52:00.001-07:00

Website/blog contains about bali travel, interesting places in Bali, temples in bali, beach, lake, waterfall, hotels in balivillas bali, bali aquaticlife, hotspring, balinightlife, watersport, kuta , nusa dua, Ubud, Uluwatu, Canggu, Legian, Seminyak,Denpasar, Tabanan, Singaraja, NusaPenida, Karangasem, Klungkung, Amed,Tulamben, Bedugul, Gitgit, Lovina, rambutsiwi, land lots, Besakih.Rute, ulundanu, shelf,mount sublime , tianyar, sekumpul waterfall, gelgel, bona, batuan, sukawati, busungbiu, menjangan island, melaya, kubutambahan, Pupuan. rice terraces, museums, art market,village, Batubulan, tampaksiring, kintamani, bangle, singaraja, buleleng, gilimanuk, toya bungkah, tegalalang, ceking, penestanan etc.

four seasons bali, bali bird park, bali safari, taro elephant park, petulu, blanco museum ubud, kedewatan

Bali travel, travel bali tips, kuta, ubud, gianyar, uluwatu, tabanan, tanah lot, bedugul, besakih, lovina, bali beach, temple of bali, nightlife, jimbaran, ngurah rai airport, nusa dua, bali villa, hotel, sanur, kintamani, tampaksiring,

Kidney Stones - Treatment Overview

2011-04-14T10:19:00.000-07:00

Your first diagnosis of kidney stones often occurs when you see your doctor or go to an emergency room because you are in great pain. Your doctor may suggest that you wait for the stone to pass and take pain medicine or have a procedure to remove the stone.

Most small stones [less than 5mm] move out of the body (pass) without the need for any treatment other than taking pain medicine and drinking enough fluids.

The smaller a stone is, the more likely it is to pass on its own. About 9 out of every 10 stones smaller than 5mm and about 5 out of every 10 stones 5mm to 10mm pass on their own. Only 1 or 2 out of every 10 kidney stones need more than home treatment.¹
The average time a stone takes to pass ranges between 1 and 3 weeks, and two-thirds of stones that pass on their own pass within 4 weeks of when the symptoms appeared.²

Not all kidney stones are diagnosed because of immediate symptoms. Your stone may not be causing you pain, and your doctor may find it during a routine exam or an exam for another condition or disease. In this case, you have the same treatment options as noted below.

Treatment for your first stone

If your doctor thinks the stone can pass on its own, and you feel you can deal with the pain, he or she may suggest home treatment, including:

Using pain medicine. Nonprescription medicine, such as nonsteroidal anti-inflammatories (NSAIDs), may relieve your pain. Your doctor can prescribe stronger pain medicine if needed.
Drinking enough fluids. You'll need to keep drinking water and other fluids when you are passing a kidney stone. If you don't get enough fluids, you could getdehydrated. Drink enough fluids to keep your urine clear, about 8 to 10 glasses a day. If you have kidney, heart, or liver disease and are on fluid restrictions, talk with your doctor before increasing your fluid intake.

Your doctor may prescribe medicine to help your body pass the stone. Alpha-blockers have been shown to help kidney stones pass more quickly with very few side effects.⁵ Ask your doctor if these medicines can help you.

If your pain is too severe, if the stones are blocking the urinary tract , or if you also have an infection, your doctor will probably suggest medical or surgical treatment. Your options are:

Extracorporeal shock wave lithotripsy (ESWL). ESWL uses shock waves that pass easily through the body but are strong enough to break up a kidney stone. This is the most commonly used medical treatment for kidney stones. See a picture of ESWL .
Ureteroscopy. The surgeon passes a very thin telescope tube (ureteroscope) up the urinary tract to the stone's location, where he or she uses instruments to remove the stone or break it up for easier removal. Occasionally, you may need a small hollow tube (ureteral stent) placed in the ureter for a short time to keep it open and drain urine and any stone pieces. Ureteroscopy is often used for stones that have moved from the kidney to the ureter. See a picture of ureteroscopy .
Percutaneous nephrolithotomy or nephrolithotripsy. The surgeon puts a narrow telescope into the kidney through a cut in your back. He or she then removes the stone (lithotomy) or breaks it up and removes it (lithotripsy). This procedure may be used if ESWL does not work or if you have a very large stone. See a picture ofnephrolithotomy .
Open surgery. The surgeon makes a cut in the side or the belly to reach the kidneys and remove the stone. This treatment is rarely used.

Should I use extracorporeal shock wave lithotripsy (ESWL) for my kidney stones?

Kidney Stones - Medications

2011-04-13T10:18:00.000-07:00

Medicine you can buy without a prescription, such as nonsteroidal anti-inflammatories (NSAIDs), may relieve your pain. Your doctor can give you stronger pain medicine if needed. NSAIDs include aspirinand ibuprofen (such as Motrin and Advil).

Your doctor may prescribe medicine to help your body pass the stone. Alpha-blockers have been shown to help kidney stones pass more quickly with very few side effects. Ask your doctor if these medicines can help you.

If you get more kidney stones despite drinking more fluids and making changes to your diet, your doctor may give you medicine to help dissolve your stones or to prevent new ones from forming. You may also receive prescription medicine if you have a disease that increases your risk of forming kidney stones. Which medicine you take depends on the type of stones you have.

Medication Choices

Medicine to prevent calcium stones

About 80% of kidney stones are calcium stones.¹ Calcium stones cannot be dissolved by changing your diet or taking medicines. These medicines may keep calcium stones from getting bigger or may prevent new calcium stones from forming:

Thiazides (such as hydrochlorothiazide, chlorthalidone) and potassium citrate(Urocit-K) are commonly used to prevent calcium stones.
Orthophosphate (Neutra-Phos) is sometimes used. It has more side effects than thiazides or potassium citrate.

Medicine to prevent uric acid stones

About 5% to 10% of kidney stones are made of uric acid, a waste product that normally exits the body in the urine.¹ Uric acid stones can sometimes be dissolved with medicine.

Potassium citrate (Urocit-K) and sodium bicarbonate (baking soda) prevent the urine from becoming too acidic, which helps prevent uric acid stones.
Allopurinol (Lopurin, Zyloprim) makes it more difficult for your body to make uric acid.

Medicine to prevent cystine stones

Less than 1% of kidney stones are made of a chemical called cystine.¹ Cystine stones are more likely to occur in families with a disease that results in too much cystine in the urine (cystinuria).

Potassium citrate (Urocit-K) prevents the urine from becoming too acidic, which helps prevent cystine kidney stones from forming.
Penicillamine (Cuprimine, Depen), tiopronin, and captopril (Capoten) all help keep cystine dissolved in the urine, which makes cystine-type kidney stones less likely to form.

Medicine to prevent struvite stones

About 10% to 15% of kidney stones are struvite stones.¹ They can also be called infection stones if they occur with kidney or urinary tract infections (UTIs). These types of kidney stones sometimes are also called staghorn calculi if they grow large enough.

Urease inhibitors (Lithostat) are rarely used because of their side effects and poor results.

What To Think About

If you have uric acid stones or cystine stones and are taking medicine to prevent more stones from forming, you will most likely have to continue taking that medicine for the rest of your life.

Some struvite stones (staghorn calculi) form because of frequent kidney infections. If you have a struvite stone, you will most likely need antibiotics to cure the infection and help prevent new stones from forming, and you will most likely need surgery to remove the stone.

TREATMENT OF YOUR KIDNEY STONES

2008-07-21T22:43:00.000-07:00

The role of medicine and diet for kidney stone treatment is mainly for the prevention of future stones or to prevent the growth of existing stones. Prevention will be addressed below.

In rare instances, stones can be dissolved. This is only effective for a smaller, purely uric acid stone and requires frequent medication adjustments and at-home urine testing up to 4 times per day by the patient.

For 90% of stones, there is no proven way to dissolve them or to medically treat a stone that has already formed.

Treatment options for most patients: non invasive, minimally invasive, and surgical procedures for kidney stone treatment and kidney stone removal.

There are some options available to treat all urinary tract stones. Kidney stone size and location is an important factor in deciding which treatment is best for you:

1. Do Nothing : This is best saved for very small stones that could pass easily, or for very large asymptomatic stones in older patients. However, if the stone is causing pain, blockage or infections, it should be treated with some medications.

2. Lithotripsy (shock wave lithotripsy, SWL, ESWL): It is the easiest procedure. The patient lies on a table or in a tub and shock waves are focused on the stone. It is non-invasive, but if the stone is over 1 cm, you will likely need a cystoscopy and stent to help the pieces pass. Patients can go home the same day. Lithotripsy is only 60 - 85% effective for making your kidney or ureter stone free in a single treatment (depending on stone size and location) . The recurrence rate is quite high. 42% of patients will have another stone within two years, probably from small fragments left behind that grow into new stones.

3. Endoscopic treatment (ureteroscopy, with or without laser stone fragmentation): A urologist can look inside the bladder and all the way up to the kidney with a small scope and either remove the stone or break it up with a laser and remove the pieces. It is minimally invasive. There is no incision as the instruments go through the patient's existing "plumbing." Patients can go home the same day. In experienced hands, the stone free rate is 90-95% for stones in the ureter. The stone free rate is 80-90% for stones in the kidney depending on size and location.

4. Percutaneous Removal (Percutaneous Nephrolithotomy) : Very few urologists are proficient at this technique, which is why many urologists will not offer it as an option for their patients. PCNL is the treatment of choice for stones over 15 - 20 mm (1.5 to 2 cm). Associated Urologists of Orange County routinely uses this technique for patients with large stones or stones refractory to other procedures.
While it is minimally invasive, it requires a one inch incision in the back. A channel is made from the skin straight into the kidney. It is invasive, but still considered minimally-invasive. Patients typically spend one night in the hospital (two for older patients). The stone free rate is 90 - 95% for these very large stones that otherwise would require multiple procedures to completely clear.

5. Open surgery: It is extremely rare to need a large incision to remove a stone from the urinary tract.

The choice of treatment will depend on the size and location of the stone. In addition, the more invasive the procedure, the higher the success rate. (Associated Urologists of Orange County)

The Signs and symptoms of kidney stones?

2008-07-18T08:44:00.000-07:00

The formation of a kidney stone generally results in severe pain in the lower back just under the ribs. The pain is not consistent but it is very intense and can last anywhere from a few seconds to a few hours. It will eventually go away for a few hours and then recur. In some cases, the pain will move down into the groin area.

Small, smooth kidney stones may remain in the kidney or pass without causing pain (called "silent" stones). Stones that lodge in the tube that carries urine from the kidneys to the bladder (ureter) cause the urinary system to spasm and produce pain. The pain is unrelated to the size of the stone and often radiates from the lower back to the side or groin.

A "small" stone (usually 4 mm in diameter or less) has a 90% chance of spontaneous passage. Stones that are 8 mm in diameter or larger usually require medical intervention.

The following are the most common symptoms of kidney stones. However, each individual may experience symptoms differently. Symptoms may include:

extreme, sharp pain in the back or side that will not go away
blood in the urine
nausea and vomiting
cloudy or odorous urine
frequent urination
a burning feeling when you urinate (pain during urination, stinging, burning)
fever, chills and loss of appetite (urinary tract infection)

Prompt medical attention for kidney stones is necessary.

The symptoms of kidney stones may resemble other conditions or medical problems. Always consult your physician for a diagnosis.

The Other Causes of Kidney Stones

2008-07-16T19:11:00.000-07:00

Heredity. There is no consensus as to why kidney stones form.: Some people are more susceptible to forming kidney stones, and heredity certainly plays a role. The majority of kidney stones are made of calcium, and hyperuricemia (high levels of calcium in the urine), is a risk factor. The predisposition to high levels of calcium in the urine may be passed on from generation to generation. Some rare hereditary diseases also predispose some people to form kidney stones. Examples include people with renal tubular acidosis and people with problems metabolizing a variety of chemicals including cystine (an amino acid), oxalate, (a type of salt), and uric acid (as in gout).

Geographical location: There is also a geographic predisposition in some people who form kidney stones. There are regional "stone belts," with people living in the Southern United States, having an increased risk. This is likely because of the hot climate, since these people can get dehydrated, and their urine becomes more concentrated, allowing chemicals to come in closer contact and begin forming the nidus of a stone.
Diet: Diet may or may not be an issue. If a person is susceptible to forming stones, then foods high in calcium may increase the risk, however if a person isn't susceptible to forming stones, nothing in the diet will change that risk.
OTC products: People taking diuretics (or "water pills") and those who consume excess calcium-containing antacids can increase the amount of calcium in their urine and increase their risk of forming stones. Patients with HIV/AIDS who take the medication indinavir (Crixivan) can form Indinavir stones.

What causes the kidney stones?

2008-07-07T05:59:00.000-07:00

A Kidney stones form when there is a decrease in urine volume or an excess of stone-forming substances in the urine. The most common type of kidney stone contains calcium in combination with either oxalate or phosphate. Other chemical compounds that can form stones in the urinary tract include uric acid and the amino acid cystine.

Dehydration through reduced fluid intake or strenuous exercise without adequate fluid replacement increases the risk of kidney stones. Obstruction to the flow of urine can also lead to stone formation. Kidney stones can also result from infection in the urinary tract; these are known as struvite or infection stones.

Men are especially likely to develop kidney stones, and whites are more often affected than blacks. The prevalence of kidney stones begins to rise when men reach their 40s, and it continues to climb into their 70s. People who have already had more than one kidney stone are prone to develop more stones. A family history of kidney stones is also a risk factor for the development of kidney stones.

A number of different conditions can lead to kidney stones:

Gout results in an increased amount of uric acid in the urine and can lead to the formation of uric acid stones.
Hyperuricemia (high calcium in the urine), another inherited condition, causes stones in more than half of cases. In this condition, too much calcium is absorbed from food and excreted into the urine, where it may form calcium phosphate or calcium oxalate stones.
Other conditions associated with an increased risk of kidney stones include hyperparathyroidism, kidney diseases such as renal tubular acidosis, and some inherited metabolic conditions including cystinuria and hyperoxaluria. Chronic diseases such as diabetes and high blood pressure (hypertension) are also associated with an increased risk of developing kidney stones.
People with inflammatory bowel disease or who have had an intestinal bypass or ostomy surgery are also more likely to develop kidney stones.
Some medications also raise the risk of kidney stones. These medications include some diuretics, calcium-containing antacids, and the protease inhibitor Crixivan (indinavir), a drug used to treat HIV infection.

The Types of Kidney Stones

2008-07-06T23:06:00.000-07:00

A kidney stone develops from crystals that separate from urine and build up on the inner surfaces of the kidney. Normally, urine contains chemicals that prevent or inhibit the crystals from forming, however, in some people, stones still become formed. Crystals that remain small enough will travel through the urinary tract and pass out of the body in the urine without even being noticed.

CALCIUM STONES
Calcium stones are the most common type of stones. Calcium is a normal part of a healthy diet and is used by bones and muscles. Calcium not used by the body goes to the kidneys where it is normally flushed out with the rest of the urine. In some people, however, the calcium that stays behind joins with other waste products to form a stone.

STRUVITE STONES
Struvite stones are a type of stone that contains the mineral magnesium and the waste product ammonia. It may form after an infection in the urinary system.

URIC ACID STONES
Uric acid stones may form when there is too much acid in the urine.

CYSTINE STONES
Cystine stones consist of cystine, one of the building blocks that make up muscles, nerves, and other parts of the body, can build up in the urine and form a stone. Cystine stones are rare. The disease that causes cystine stones (cystinosis) runs in families.

What is a kidney stone?

2008-07-06T19:45:00.000-07:00

A kidney stone is a hard mineral and crystalline material formed within the kidney or urinary tract. A kidney stone is also a solid piece of material that forms from crystallization of excreted substances in the urine. The stone may remain in the kidney or break loose and travel down the urinary tract. A small stone may pass all of the way out of the body, but a larger stone can get stuck in a ureter, the bladder, or the urethra. This may block the flow of urine and cause great pain.

A kidney stone may be as small as a grain of sand or as large as a pearl, and some are as big as golf balls. Approximately 80 percent of kidney stones are less than 2 centimeters in width. They may be smooth or jagged, and are usually yellow or brown in color.

Kidney stones are a common cause of blood in the urine and often severe pain in the abdomen, flank, or groin. Kidney stones are sometimes called renal calculi. One in every 20 people develops a kidney stone at some point in their life.The condition of having kidney stones is termed nephrolithiasis or urolithiasis. (healthsystem.virginia.edu)