Kidney stone is a seemingly simple disease, but it is actually a complex one. It is simple because anyone can diagnose it once it strikes, but its pathogenesis is very complex. Therefore, it is very important to have a comprehensive understanding of the causes and pathogenesis of kidney stones, especially how to prevent the formation of stones. This article is worth reading for its clear explanation of the causes, the formation mechanism of kidney stones, and how to treat and prevent them.
Almost every doctor will encounter patients with kidney stones in their medical career, so we all think that kidney stones are a common disease, but have you really done your best to educate patients about this common disease, which is not complicated to diagnose and treat?
Let’s take a look at how the experts at the Mayo Clinic, which has been ranked among the best specialties in the United States this year, are educating their patients about kidney stones, and hopefully the content of this article will help clinicians better answer their patients’ questions in their daily work. The following content is compiled from the MayoClinic website.
Overview of kidney stones
Kidney stones are small, hard deposits of minerals and acidic salts that form in the kidneys. Stones usually form easily when the urine is concentrated and mineral crystals precipitate. The process of removing stones from your body can be very painful, but stones usually do not cause permanent damage. Depending on the situation, you may only need to take pain medication and drink a lot of water to get rid of the stone, or you may need surgery to remove a large stone that is blocking your urinary tract. If you are at high risk for stone recurrence, your doctor may recommend preventive treatment to reduce the risk of recurrence.
Symptoms of kidney stones
A kidney stone may not cause symptoms, but when it moves in the kidney or drains into the ureter, it can produce the following symptoms: (1) severe pain on either side of the lower ribs or in the back; (2) pain that spreads to the lower abdomen and groin; (3) paroxysmal pain; (4) painful urination; (5) pink, red, or brown urine; (6) cloudy or foul-smelling urine; (7) nausea and vomiting; (8) A constant need to urinate; (9) Urinating more often than usual but in smaller amounts each time; (10) Fever and chills if an infection develops.
If you have: (1) severe pain that makes you restless and you cannot find a comfortable position; (2) pain with nausea and vomiting; (3) pain with fever and chills; (4) blood in the urine; (5) difficulty urinating.
Causes of kidney stones
Although some factors can increase the risk of kidney stones, there is no single clear cause of kidney stones. Stones form when your urine contains more of the substances that form crystals (such as calcium, oxalic acid and uric acid) and less of the fluid that can be diluted in your urine. At the same time, your urine lacks substances that prevent the crystals from sticking together, creating an ideal environment for stones to form.
Types of kidney stones
Knowing the types of kidney stones can help clarify the cause and provide clues to reduce the formation of more kidney stones. Types of stones include.
1. Calcium-containing stones: Most kidney stones are calcium-containing stones, usually in the form of calcium oxalate. Oxalic acid is a naturally occurring substance found in foods. Some fruits and vegetables, as well as nuts and chocolate, are rich in oxalic acid. Your liver can also produce oxalic acid. Dietary factors, high doses of vitamin D, gastrointestinal bypass surgery and a variety of metabolic disorders can increase the concentration of calcium or oxalic acid in the urine. Calcium-containing stones can also manifest in the form of calcium phosphate.
2. Guano stones: Guano stones usually form in response to an infection, such as a urinary tract infection. These stones grow rapidly, become large, and some do not cause symptoms or have only mild warning signs.
3. Uric acid stones: Uric acid stones usually form in people who do not consume enough fluids, lose a lot of fluids, consume a high protein diet, and have gout. Certain genetic factors can also increase your risk of developing uric acid stones.
4. Cystine stones: These stones usually form in patients with a genetic disorder (where the kidneys excrete too much cystine to form cystinuria).
5. Other types of stones: Other rare types of kidney stones can also occur.
Risk factors for kidney stones
1. Family or personal history: You are more likely to have kidney stones if someone in your family has had kidney stones. If you already have 1
or more kidney stones, then you are at increased risk of developing another kidney stone.
2. Dehydration: Inadequate daily water intake increases your risk of developing kidney stones. People who live in tropical climates and those who sweat more have a higher risk of developing kidney stones than others.
3. Specific dietary habits: A diet high in protein, salt and sugar may increase the risk of certain types of kidney stones, especially a high-salt diet, because too much sodium in the diet increases the amount of calcium in the kidneys.
4. Physical obesity: Higher body mass index (BMI), large waist circumference and weight gain are associated with an increased risk of kidney stones.
5. Digestive disorders and surgical history: Gastrointestinal bypass surgery, inflammatory bowel disease or chronic diarrhea can lead to changes in the digestive process, which can affect the absorption of calcium and water and increase the level of stone forming substances in the urine.
6. Other medical conditions: including renal tubular acidosis, cystinuria, hyperparathyroidism, certain medications and some urinary tract infections.
Testing and diagnosis of kidney stones
1. Blood test: A blood test may reveal high blood calcium or blood uric acid levels. The blood test results help monitor the health of your kidneys and help your doctor find out if there are any other medical conditions.
2. Urine test: A laboratory test that collects 24h
The results of a laboratory test performed on urine may indicate that you are excreting too much of the minerals that cause stones to form or too little of the substances that prevent stones from forming. For this test, your doctor may ask you to have two urine collections in 2 consecutive days.
urine collection twice a day.
3. Imaging: Imaging tests may show that you have stones in your urethra. The imaging test options are varied and can range from a simple plain abdominal radiograph (which may miss small kidney stones) to a high-speed or dual-energy
CT (which may find very small kidney stones). Other imaging methods include ultrasound (a noninvasive test) and intravenous urography (which requires the injection of contrast from a vein in the arm) followed by X-ray (intravenous renal stone).
(intravenous pyelogram) or under CT (CT urography).
4. Stone composition analysis: Your doctor may ask you to use a filter to catch the stone you pass while urinating. A laboratory stone composition analysis will reveal the composition of your kidney stones. Your doctor will use this information to determine the cause of your kidney stones and to develop a plan to prevent more kidney stones from developing.
Treatment of kidney stones
Treatment for kidney stones varies depending on the type of stone and the cause.
1. Treatment of small kidney stones causing mild symptoms: Most kidney stones do not require invasive treatment, and patients can expel small stones by.
(1) Drinking water: Keep the daily water intake between 1.9L and 2.8L to help flush the urinary system. Take in as much fluid as possible, mainly water, to produce clean or nearly clean urine.
(2) Pain relievers: Small stones can cause discomfort when they are expelled. To relieve mild pain, your doctor may recommend antipyretic analgesics such as ibuprofen, acetaminophen and naproxen.
(3) Medication: Your doctor may prescribe medication to help the stones pass. This type of medication is called an alpha blocker and relaxes the muscles of the ureter to help you expel the kidney stone faster with less pain.
2. Treatment of large kidney stones that cause significant symptoms: Kidney stones that cannot be treated with conservative measures (these stones are either too large to pass out of the body on their own or cause bleeding, kidney damage or persistent urinary tract infections during the process of passing) may require intensive treatment. Treatment measures include.
(1) Use of sound waves to crush the stone: For some stones (depending on size and location), your doctor may recommend extracorporeal shock wave lithotripsy (ESWL). ESWL uses sound waves to create strong vibrations in order to crush the stone into small pieces that can pass through the urethra. The entire procedure lasts about 45-60 minutes and can be moderately painful. ESWL can be performed under sedation or light anesthesia for comfort, but it can cause hematuria, bruising on the back or abdomen, bleeding from the kidneys and adjacent organs, and discomfort as the stone passes through the urethra.
(2) Surgical removal of very large kidney stones in the kidney: A procedure called “percutaneous nephrolithotomy” is performed to remove kidney stones by inserting a small telescope and equipment instruments through a small incision in your back. You will be under general anesthesia during the procedure and will need to stay in the hospital for 1-2 days for observation and recovery. When ESWL is unsuccessful, your doctor may recommend this procedure.
(3) Stone removal using laparoscopy: To remove smaller stones in the ureter or kidney, the doctor may insert a thin lighted tube (ureteroscope) equipped with a camera through the patient’s urethra and bladder into the ureter. Once the stone is positioned, special tools can capture the stone or crush it into small pieces that can pass through the urethra. Next, a small tube (stent) is placed in the ureter to reduce swelling and speed healing. General or local anesthesia may be required for this procedure.
(4) Surgery of the parathyroid glands: Some calcium and phosphorus stones are due to overactive parathyroid glands. The parathyroid glands are located in the orientation of the four corners of the thyroid gland. When the parathyroid glands secrete too much parathyroid hormone, the blood calcium level in the body rises significantly, forming kidney stones. Hyperparathyroidism sometimes occurs as a benign, tumor-like growth of the parathyroid glands. Surgical removal of the hyperplastic parathyroid glands can prevent kidney stones from forming.
Prevention of kidney stones
1.Lifestyle changes
(1) Drink more water throughout the day: For people with a history of kidney stones, doctors usually recommend that the daily urine volume should be about 2.5L. Your doctor may ask you to record your urine volume to determine if you are drinking enough water. If the patient lives in hot, dry weather or does regular physical activity, he or she will need to drink more water to produce enough urine. If your urine is clear and bright, then it is likely that you are drinking enough water.
(2) Eat less oxalic acid-rich foods: If you are prone to forming calcium oxalate stones, then your doctor may recommend that you limit your intake of oxalic acid-rich foods. These foods include rhubarb, beets, okra, spinach, Swiss chard, sweet potatoes, nuts, tea, chocolate, and soy products.
(3) Choose a diet low in salt and animal protein: You should reduce the amount of salt in your diet and choose non-animal protein sources of protein, such as beans. Consider using salt substitutes.
(4) You can continue to eat calcium-rich foods, but use calcium supplements with caution: Calcium in foods has no effect on the risk of developing kidney stones. You can continue to consume calcium-rich foods unless your doctor advises against it. Seek your doctor’s advice before taking calcium supplements, as they are associated with an increased risk of kidney stones, which can be reduced by taking them with meals. A low-calcium diet can also increase the risk of kidney stone formation in some people. You can see a dietitian to help you develop a diet plan to reduce the risk of kidney stones.
2. Medication
Medications can control the amount of minerals and acids in the urine and can be helpful for some people with certain types of stones. The type of medication your doctor prescribes depends on the type of kidney stone you have. Here are some examples.
(1) Calcium-containing stones: To prevent calcium-containing stones from forming, your doctor may prescribe a thiazide diuretic or a phosphorus-containing preparation.
(2) Uric acid stones: The doctor may prescribe allopurinol to lower the level of uric acid in the blood and urine, and may also prescribe drugs to alkalize the urine. In some cases, allopurinol and alkalizing drugs may be able to dissolve uric acid stones.
(3) Guano stones: To prevent guano stones, the doctor may recommend strategies to keep the urine sterile (since the presence of bacteria in the urine can cause urinary tract infections). Long-term use of small doses of antimicrobials may help achieve this goal. For example, physicians may recommend the use of antimicrobials before and after surgical procedures to treat kidney stones.
(4) Cystine stones: Cystine stones can be difficult to treat. The doctor may recommend that the patient drink more water to produce more urine. If drinking more water alone does not work, the doctor may also prescribe a medication that lowers the amount of cystine in the patient’s urine.