How does the kidney filter blood?

How does the kidney filter blood?Many people do not realize how vital their kidneys are to their overall health until an issue arises and they need to seek medical care. Knowing what your kidneys do and how they function can go a long way toward maintaining good health before a problem occurs or understanding the treatment process once you are under a urologist’s supervision.

What Do My Kidneys Do?

Your kidneys are basically your body’s filtration system. Every minute, approximately half a cup of blood flows through them. As the blood flows through, waste products are removed, as is excess water; the levels of minerals and salt are also adjusted if need be. Although around 150 quarts of blood are filtered by your kidneys every day as it continually cycles through your body, only about 1-2 quarts of urine are produced from the waste products and excess water. The urine then flows to the bladder through a tube called the ureter.

How Do My Kidneys Work?

Inside each kidney, there are about a million tiny filtration units called nephrons. The nephrons are made up of a filter called a glomerulus and a tube called a tubule. Blood flows through the glomerulus, where waste and excess water or minerals are filtered out. The tubule then sends the filtered substances to collect in the kidneys before flowing through the ureter to the bladder, while the newly-filtered blood is returned to the rest of the body. There are so many nephrons in your kidneys that even if more than half of them are no longer working, you may not notice any issues or symptoms.

What Happens If Something Goes Wrong?

Many things can occur to interrupt the function of your kidneys. Warning signs of kidney disease include an increased need to urinate, especially at night, blood in the urine, foamy urine, cramping muscles and swollen ankles and feet. These are all signs that something could be wrong with the filtration system in your kidneys, causing issues with fluid and electrolyte levels in your body.

Another common problem is kidney stones. When there is a buildup of certain waste products in the kidneys and not enough fluid to flush them out, these waste products can crystallize and form stones that cause extreme pain as they leave the body. If you suspect you are dealing with kidney stones, kidney disease, or other problems with your urinary system, it’s important to talk to a doctor right away, like the urologists at St Pete Urology, who will be able to diagnose any issues and help you and your kidneys return to normal healthy function as soon as possible.

For more information, visit the St Pete Urology website.

How can I prevent recurrent kidney stones

Kidney stones occur when tiny crystals form and stick together as solid masses in urine. Often, due to increased concentration of various chemicals in urine, crystals form and then grow into larger masses that move through the urinary tract. As they move, the stones may get stuck somewhere along the tract and block urine flow, causing pain. Most kidney stones are a combination of calcium with either oxalate or phosphate, but stones also may form when uric acid levels increase in urine as a result of protein metabolism.

Preventing kidney stone recurrence

For many people who have had a kidney stone, it is not a one-time thing. In fact, in about 50 percent of those who have had a stone, another one will appear within 7 years if no preventive measures are in place. At St Pete Urology, we ensure that our patients take the necessary steps to prevent a recurrence. That is why, after treatment, we conduct a special urine test on our patients to find out why the stone formed in the first place. Using the results of the test, we guide our patients on how best they can avoid a recurrence.

Some of the measures we recommend to avert kidney stone recurrence include:

1. Drinking enough water

Water dilutes urine, reduces the concentration of substances in it and prevents kidney stones. To prevent recurrent kidney stones, you should endeavor to drink enough fluid to pass at least 2 liters of urine per day. Increased fluid intake that is distributed throughout the day decreases kidney stone recurrence by about 50 percent and with virtually no adverse effects.

For better results, you may add orange juice or lemonade to the water so there is increased citrate in the fluid to block stone formation. Medication such as allopurinol, citrate or a thiazide diuretic can be taken with the fluid to minimize the chance of kidney stone recurrence. However, if you are already drinking that much fluid before your kidney stones, you should not increase your fluid intake.

2. Making dietary changes

Once you are treated for kidney stones, we will recommend that you reduce your intake of eggs, seafood, poultry, red meat and other animal protein. These foods increase uric acid levels while also reducing citrate levels in the body, which can trigger a recurrence of kidney stones. That is why after treatment for kidney stones, we recommend that you should cut down your daily meat portions to a size no larger than a pack of playing cards. Likewise, you should avoid foods such as chocolate, strawberries, wheat bran, beets, spinach, tea, rhubarb and most nuts that contain oxalate or the phosphate containing colas that may trigger kidney stone recurrence.

3. Increasing calcium intake

Oxalate levels may rise and trigger kidney stones if the level of calcium in the diet is low. So after treatment, it is important to ensure that you increase your calcium intake to match your age. For example, if you are a man 50 and older, you should get 1,000 milligrams of calcium every day, together with 800-1000 IU (international units) of vitamin-D to ensure your body absorbs the calcium properly. With increased dietary calcium, you can prevent a recurrence of kidney stones.

4. Reduced sodium intake

Kidney stones may recur if there is a lot of sodium in your diet because increased sodium leads to high concentration of calcium in urine. So after treatment for kidney stones, we usually recommend that you lower the amount of sodium in your diet, limiting your total daily sodium to 2,300 mg. But if sodium was responsible for your previous kidney stones, then we recommend that you should take at most 1,500 mg of sodium per day. Such a low level of sodium also will be good for your heart and your blood pressure.

Those are some of our most common recommendations for averting kidney stone recurrence. As you might have noticed, they are not complicated things to do, but they do require some commitment. For more information on prevention and treatment of kidney stones, visit the “St Pete Urology” site.

How long should it take to pass a kidney stone?

Most kidney stones will pass through the ureter to the bladder and out of the body when given time. In fact, with ample fluid intake, nearly all kidney stones will pass through the urinary tract on their own within 48 hours. Nevertheless, the time it takes for a stone to be passed depends on its size and location in the urinary tract. For instance, smaller stones and those located in the lower portion of the urinary tract (closer to the bladder than the kidneys), have a higher likelihood of passing on their own and tend to pass more rapidly. Larger stones and those located in the kidneys are less likely to pass on their own and tend to pass more slowly.

How long does it take to pass a kidney stone?

According to the American Urological Association, the length of time required to pass a kidney stone located in the ureters (tube that connects kidneys to the bladder), is an average of 8 days if the stone is less than 2mm, about 12 days for a stone between 2mm and 4mm, and 22 days if the stone is between 4mm and 6mm. Generally, however, most kidney stones will pass on their own in 40 days. But when a medical expulsive therapy is applied, a kidney stone (2mm to 6mm) will pass within a few days or weeks provided the patient is in good health. Medications called antispasmodics can be used to accelerate the process of passing a stone. The drugs relax the ureters and increase the speed of passing a stone by up to 5-7 days. A urologist may allow for up to 6 weeks for a kidney stone to pass on its own, but earlier intervention may be necessary if the stone is causing severe pain, gastric discomfort or urinary problems.

Factors affecting the ability to pass a kidney stone

There are several factors that affect the ability to pass a kidney stone. They include:

  1. Prostate enlargement.
  2. Size of the person.
  3. Prior stone passage.
  4. Pregnancy.
  5. Size of the stone.
  6. Location of the stone.

For instance, a kidney stone that is 4mm in size has an 80 percent chance of passing while a stone that is 5mm in size has only a 20 percent chance. Kidney stones that are larger than 9mm-10mm can hardly pass without a doctor’s intervention and require timely treatment to avoid complications. To increase the passage rate of kidney stones, a urologist may recommend certain medications. The medications include alpha blockers such as tamsulosin (Flomax) and calcium channel blockers such as nifedipine (Procardia, Nifediac, Adalat or Afeditab).

Dealing with the symptoms of a kidney stone

Since most kidney stones will eventually pass through the urinary tract and out of the body when given time, treatment is usually directed toward controlling the symptoms. When the stones are passed at home, appropriate interventions usually include increased fluid intake and taking anti-inflammatory drugs such as Ibuprofen. If over-the-counter pain medications are ineffective, stronger drugs such as Ketorolac (an injectable anti-inflammatory drug) and narcotic pain medications are used. In case of severe nausea and vomiting, the doctor may give intravenous medications.

When do kidney stones require removal?

Waiting for kidney stones to pass is not ideal for every case. According to the American Urological Association, kidney stone removal should be considered if a stone fails to pass on its own within 2 months. Likewise, stone removal is necessary if complications arise due to the stone. Complications that require stone removal include ureter blockage or irritation, urinary tract infection, decreased kidney function and uncontrolled pain, nausea or vomiting.

To remove kidney stones, a procedure called lithotripsy is often used. During the procedure, kidney stones are subjected to shock waves, resulting in the breakdown of larger stones into smaller pieces that can easily pass through the urinary tract. When lithotripsy is not effective, surgical techniques may be necessary to remove kidney stones. This may be done either by making a tiny incision in the skin (percutaneous nephrolithotomy) or via an instrument (called ureteroscope) passed through the urethra and bladder into the ureter.

Effective treatment at St Pete Urology

At St Pete Urology, we provide a multidisciplinary approach to treating and managing kidney stones of all sizes. We have assembled a highly integrated team of nephrologists, urologists, radiologists and dietary and metabolic specialists to ensure comprehensive diagnosis, treatment and proper assessment of the risks leading to the formation of kidney stones. By applying the latest technology in treating kidney stones (including state-of-the-art lasers) and a broad range of noninvasive and minimally-invasive procedures for removing small and large stones, we guarantee only the highest quality and successful treatment to all our patients. For more information, visit the St Pete Urology site.

What does it feel like when you have a kidney stone?

Formed by crystallization of certain substances in urine, kidney stones are hard, pebble-like pieces of materials occurring in one or both kidneys when there are high levels of various minerals such as calcium or uric acid in urine. A kidney stone may be as small as a grain of sand, as big as a pebble or even as large as a golf ball. Generally, the larger the stone the more severe the symptoms. If the stone is very small in size, it can pass through your urinary tract without notice. But a large stone may cause a sharp pain in your side, groin, back or lower abdomen as it passes through the urinary tract.

So what does it feel like when you have a kidney stone?

Typically, kidney stones are formed in the kidney and a stone that remains in the kidney rarely causes pain. But when a kidney stone travels through the tubes of the urinary tract such as the ureter (tube connecting the kidney to the bladder) or the urethra (tube that leads outside the body), it may produce irritation and blockage that result in pain and other symptoms. You may feel the following symptoms depending on the size and location of the stones:

  1. No symptoms, if the stone is very small.
  2. Sudden and severe pain on the side, lower back, groin, abdomen or genitals. The pain gets worse in waves and is often described by people with kidney stones as “the worst pain I have ever experienced.”
  3. Nausea and vomiting, or a persistent stomach ache.
  4. Foul-smelling or cloudy urine
  5. Blood in urine, which occurs whether the stones remain in the kidney or travel through the ureters.
  6. Frequent and painful urination, often occurring when the kidney stone is in the ureter or after the stone has passed the bladder and is located in the urethra. In some cases, painful urination indicates a urinary tract infection occurring concurrently with the stones.

Remember there are other conditions, such as hernias, appendicitis, prostatitis and ectopic pregnancy, which may have the same symptoms. Therefore it is important to see a urologist so your condition is accurately diagnosed.

Abdominal and back pain

Kidney stones may occur in the urinary tract without causing any symptoms. In fact, if you have small stones, they are likely to pass through the urinary tract without causing pain or being noticed. However, this is often only possible before the stones move from your bladder into the ureter. Once inside the ureter or other tube of the urinary tract, kidney stones cause irritation and blockage which may lead to considerable pain and discomfort. The pain may begin while a stone is still in the kidney or after the stone moves into the ureter, urethra or bladder.

If the pain occurs while the stone is still in the kidney, it is felt in the side and on the back, typically on the same side of the body as that of the affected kidney. You also may feel a cramping sensation or a sharp pain in the pelvic area, lower abdomen or in the genitals.When pain is related to the movement of a stone through the urinary tract, it comes in waves and builds in intensity before fading in cycles of every 20-60 minutes.

Physical signs

As kidney stones move through the urinary system, you may feel a strong and frequent urge to urinate. Likewise, the movement of the stone can cause irritation and damage to the lining of the bladder or ureter, causing blood to mix with urine. As a result, you will find yourself passing bloody urine, which appears reddened, pink or rusty in color. The urine also can be cloudy or foul-smelling. Kidney stones may cause gastric distress, nausea and vomiting. If the movement of the stones through the urinary tract triggers an infection, you may experience fever and chills.

Seek prompt treatment

When you feel lasting symptoms or complications due to kidney stones, it is important to seek prompt treatment. At the doctor’s office, you will undergo thorough examination and diagnostic testing to confirm your condition. If you are diagnosed with kidney stones, your treatment will depend on the size and location of the stones. For example, if you have small kidney stones, the urologist may recommend increased fluid intake to enable the stones to pass on their own. But if the stones are large, the doctor may use a scope to remove them. In some cases, surgery may be necessary.

If you suspect that you have kidney stones, visit St Pete Urology for accurate diagnosis, effective treatment and comprehensive care. At St Pete Urology, we have successfully treated kidney stones and other urinary tract problems for several years. For more information, visit the “St Pete Urology” site.

Infographic: Everything You Need to Know About Kidney Stones

Everything You Need to Know About Kidney Stones

People sometimes may have kidney stones for several years without experiencing severe symptoms. The stones may pass out in urine with little pain and just a few mild-to-moderate symptoms. However, whether you have not had a kidney stone or only experienced a little pain when passing a stone, it is advisable to take precautionary steps to avoid more serious problems. For example, eating certain types of foods such as large amounts of lemons and oranges may cause kidney stones. But before eliminating various food items from your diet, you should consult a urologist. The urologist will conduct a proper evaluation of your current health status and provide clear guidance on which foods may cause kidney stones.

Common symptoms

A kidney stone often shows no symptoms until it has moved into the ureter. And when symptoms finally show, they commonly include:

  • Sudden, severe pain in the groin or in the side of your abdomen
  • A burning sensation during urination
  • Pain and difficulty during urination
  • A persistent urge to urinate
  • Reduced quantity of urine excreted
  • Nausea and vomiting
  • Blood in urine
  • Pus/white blood cells in urine
  • Chills and fever (if there is an infection)
  • Causes of Kidney Stones

Kidney stones typically vary in size, with some capable of growing as large as golf balls. The most common cause of the stones is lack of water in the body. The condition is often found in people who drink less than the recommended 8-10 glasses of water per day. When there is inadequate water in the body to dilute uric acid (a core component of urine), the urine will become more acidic and create a perfect environment for formation of the stones. Medical conditions like renal tubular acidosis, Dent’s disease, medullary sponge kidney, hyperparathyroidism, urinary tract infections and Crohn’s disease also increase the risk of kidney stones.

For prevention of kidney stones, you should:

  • Drink 2.5-3 liters of water every day
  • Reduce sodium or salt intake in your diet
  • Follow a healthy diet and avoid red meat. Daily or frequent consumption of red meat may cause kidney stones.
  • Exercise regularly and make sure to get enough sleep
  • Quit smoking and avoid alcohol
  • Treatment for kidney stones

The treatment is usually focused on managing the symptoms since passing a stone may be really painful. In the hospital, a urologist may choose:

  • Rehydration via an intravenous tube, accompanied with anti-inflammatory medication. Narcotics may be used to reduce the pain of passing the stones while antiemetic medication may be given to stop nausea and vomiting.
  • Extracorporeal shock wave lithotripsy (ESWL) may be performed by a urologist to break a kidney stone into small pieces to enable it to pass.
  • Laser surgery with ureteroscopy may be performed for large stones located in areas that do not allow for lithotripsy.
  • PNL/PCNL, flexible ureteroscopy, also may be considered by a urologist.

At St. Pete Urology, we offer many options and state-of-the-art facilities for successful treatment of kidney stones. For more information, visit the site, St Pete Urology.

Causes of Kidney Stones and Treatment Options

The United States has been experiencing a rise in the number of people with kidney stones over the last 30 years. While less than 4 percent of the population had the disease in the late 1970s, the portion of the population with the disease increased to over 5 percent by the early 1990s, and today 1 in 11 Americans has kidney stones. The stones occur more frequently in men than women, with Caucasians being more prone to developing the stones than African Americans.

The prevalence of the stones increases dramatically as men reach their 40s and continues to increase into their 70s. But for women, the occurrence of the stones peaks in their 50s. After a person gets more than one stone, the chance of other stones developing increases radically.

What causes kidney stones?

The major cause of kidney stones is a lack of fluids in the body, which allows minerals and salts to concentrate and crystallize over weeks or months to form the stones. Most often, the stones result from a build-up of certain chemicals in the body, such as ammonia, calcium, uric acid or cysteine. You are more likely to have kidney stones if you do not drink enough fluids.

It is also believed that high-oxalate foods such as spinach, peanuts, sweet potatoes, chocolate, okra, black Indian tea, wheat germ, beets and rhubarb, may increase the risk of developing kidney stones. In the South, often referred to as the stone belt, people tend to be dehydrated in the summer and drink a lot of tea, increasing the chances of developing stones.

You are also more likely to have kidney stones if you:

  • Are between 30-50 years old
  • Have a family history of kidney stones
  • Have hypercalciuria (unusually high amounts of calcium in urine).
  • Are taking certain medicines, such as diuretics (like triamterene) or protease inhibitors (like indinavir)
  • Are taking too much antacids, calcium, vitamin C or vitamin D supplements.
  • Have metabolic syndrome (a combination of many heart disease risk factors like high blood pressure, high sugar, unhealthy cholesterol levels and obesity)
  • Have a condition such as hyperthyroidism, gout or high blood pressure
  • Have cystitis
  • Have a condition that affects the structure or shape of your ureters or kidneys

Even though small kidney stones are often asymptomatic and may pass with little or no pain, large stones that block the urine’s path may cause severe symptoms. These could include sharp pain in the lower back or abdomen, painful urination, fever and chills, nausea and vomiting, blood in urine, and abnormally colored urine. It is important to visit your urologist if you experience such symptoms. The urologist will order blood and urine tests and imaging, and recommend appropriate treatment.

At St Pete Urology in St. Petersburg, we use minimally-invasive techniques and have a wide array of treatment options for kidney stones. If you think you may have kidney stones or have questions about the condition, visit the St Pete Urology website.

7 Common Symptoms of Kidney Stone and Treatment Options

The symptoms of kidney stones are largely determined by the size of the stones. For small kidney stones, the symptoms may be mild. In fact, small stones may go undetected and pass out of the body painlessly during urination. The most common symptom of kidney stones is pain which begins as a vague sensation then becomes sharp and severe as ureter muscles contract and relax around the stones. Initially, the pain is felt on the flanks or on the sides of the body, between the pelvis and ribs, including the lower back and upper abdomen. Later it moves to the groin or testicles as the kidney stone moves through the urinary tract.

Generally, the symptoms of kidney stones follow the migration of the stone across the urinary tract. The symptoms will depend on whether the stone gets stuck in the kidney, begins to travel down the ureter, or causes an infection.

Therefore, depending on the size of the stone, symptoms may include:

  • Sharp, persistent and severe ache in the side and back, often below the ribs
  • Pain which spreads to the groin and lower abdomen
  • Pain occurring in waves and with fluctuating intensity
  • Pain when passing urine
  • Restlessness and inability to lie still
  • Nausea and vomiting
  • Red, pink or brown urine
  • Foul smelling or cloudy urine
  • Urge to pass urine more often than usual
  • Urinating small quantities of urine
  • Chills and fevers if there is an infection

Blood in urine, often caused by the stone scratching the ureter or kidney
A kidney stone may cause an infection when it has blocked the ureter, preventing waste products from passing the blockage and resulting in bacterial build-up. It is the infection that causes symptoms such as fever, chills and shivering, diarrhea, foul smelling and cloudy urine, and fatigue.

Symptoms of Kidney Stone and Treatment OptionsIf you have these symptoms, it is important to see a physician, preferably a urologist. The doctor will perform a medical and symptomatic history, give a physical exam and order the necessary tests to confirm the presence of kidney stones and determine their size, location and appropriate treatment. The tests may include blood tests (like uric acid, calcium and phosphorous), tests for stone-forming salt crystals, infections, blood cells and stone factors, kidney function tests, and imaging tests (kidney ultrasounds, CT scans, MRI scans, abdominal X-rays and intravenous pyelograms). The urologist will recommend appropriate treatment after confirming the presence of stones.

If small, less-troublesome stones are detected, the urologist may recommend drinking 8-16 cups of water to flush them out. Along with the recommendation to drink plenty of fluid, the urologist may prescribe pain relievers such as ibuprofen, naproxen sodium or acetaminophen. In some cases, the urologist may offer a medication to help pass small stones from the kidney. The medication, called an alpha blocker, helps to relax ureter muscles and allows the stones to move quickly and painlessly out of the urinary tract.

Large stones are accompanied by various symptoms and should be treated using stronger measures. The urologist may use sound waves to break up the stones, a procedure called extracorporeal shock wave lithotripsy (ESWL). In some cases, the urologist will use a scope (a thin lighted tube equipped with a camera) to remove the stones. The urologist may also opt for percutaneous nephrolithotomy to surgically remove large stones, or even parathyroid gland surgery when necessary.

At St Pete Urology, we have experienced urologists and state-of-the-art facilities to ensure prompt diagnosis and effective treatment of kidney stones. If you have questions about this condition, visit St Pete Urology in St Petersburg for quality medical care.