PERSONALIZED PATIENT CARE
The urinary tract, or system, consists of the kidneys, ureters, bladder, and urethra. The kidneys are two bean-shaped organs located below the ribs toward the middle of the back. They remove extra water and wastes from the blood, converting it to urine. They also keep a stable balance of salts and other substances in the blood. The kidneys produce hormones that help build strong bones and help form red blood cells. Narrow tubes called ureter carry urine from the kidneys to the bladder, an oval-shaped chamber in the lower abdomen. Like a balloon, the bladder's elastic walls stretch and expand to store urine. They flatten together when urine is emptied through the urethra to outside the body.
One in every 20 people develops a kidney stone at some point in their life. A kidney stone is a hard mineral and crystalline material formed within the kidney or urinary tract.
Kidney stones are one of the most common disorders of the urinary tract. In the year 2000, patients made 2.7 million visits to health care providers and more than 600,000 patients went to emergency rooms for kidney stone problems. Men tend to be affected more frequently than women. The function of the kidneys (Renal) is to remove waste products and unwanted water from the blood, in the form of urine. If there is too much of certain waste products in the urine, these substances form crystals. Crystals can then combine to form stones.
A kidney stone is a hard mass developed from crystals that separate from the urine and build up on the inner surfaces of the kidney. Normally, urine contains chemicals that prevent or inhibit the crystals from forming. These inhibitors do not seem to work for everyone, however, so some people form stones. If the crystals remain tiny enough, they will travel through the urinary tract and pass out of the body in the urine without being noticed. However, when they pass down the ureter on their way to the bladder, pain usually occurs with anything but the smallest stone. If a stone gets stuck on its way down the ureter, pain usually occurs in the form of renal colic. The pain comes and goes in waves. Blood may be passed as well, due to the irritation of the lining of the ureter by the sharp-edged stone.
Kidney stones, one of the most painful of the urologic disorders, are not a product of modern life. Scientists have found evidence of kidney stones in a 7,000-year-old Egyptian mummy.
Urolithiasis is the medical term used to describe stones occurring in the urinary tract. Other frequently used terms are urinary tract stone disease and nephrolithiasis. Doctors also use terms that describe the location of the stone in the urinary tract. For example, a ureteral stone (or ureterolithiasis) is a kidney stone found in the ureter. To keep things simple, however, the term "kidney stones" is used throughout this fact sheet.
Calcium stones are most common. They are two to three times more common in men, usually appearing at age 20 to 30. Recurrence is likely. The calcium may combine with other substances such as oxalate (the most common substance), phosphate, or carbonate to form the stone. Oxalate is present in certain foods. Diseases of the small intestine increase the tendency to form calcium oxalate stones.
Uric acid stones are also more common in men. They are associated with gout or chemotherapy. Uric acid stones make up about 10% of all stones.
Cystine stones may form in persons with cystinuria. It is a hereditary disorder affecting both men and women.
Struvite stones are mainly found in women as a result of urinary tract infection. They can grow very large and may obstruct the kidney, ureter, or bladder.
Stones may develop just because the urine is very concentrated. Not surprisingly, stones are therefore more likely to occur in hot climates. On the other hand, stones can occur because the output of a given chemical waste product is increased. Calcium stones occur when there is too much calcium in the urine. This may happen if there is too much calcium in the diet from milk, cheese or bread. Some people seem to absorb more calcium from the gut and there is nowhere for it to go other than into the urine. Other people may have an overactive parathyroid gland (hyperparathyroidism). This results in calcium being leaked out of the bones and again it has nowhere else to go but the urine. More often, no obvious cause can be found. Oxalate stones can occur if there is too much oxalate in the diet (spinach, rhubarb, chocolates and certain nuts). They are more likely to occur in people who have a bowel problem in which fat is not being absorbed properly. Uric acid stones form when there is too much uric acid in the urine. This comes as a direct result of too much uric acid in the blood. This is particularly likely in people who are prone to the condition of gout. Struvite stones are associated with chronic Urinary tract infection. Cystine stones arise when Urine becomes supersaturated with cystine and leads to crystal deposition. 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.
Most calculi originate within the kidney and proceed distally, creating various degrees of urinary obstruction as they become lodged in narrow areas, including the ureteropelvic junction, pelvic brim, and ureterovesical junction. Location and quality of pain are related to position of the stone within the urinary tract. Severity of pain is related to the degree of obstruction, presence of ureteral spasm, and presence of any associated infection. So the symptomatic presentation of renal calculi has been described below:
An abdominal x-ray may show certain types of stones. An ultrasound test is usually able to confirm where the stone is lying, and the effect that it is having on the other structures. Sometimes, a special kidney x-ray (intravenous pylogram: IVP or intravenous urogram: IVU) needs to be done to show the position of the stone and to find out if there is any blockage. This is done by giving an injection into the arm vein. Several x-rays are taken over the next 2 hours. This shows the stones in the kidneys, ureter or bladder. It will also show whether any stone is producing a blockage. It is also important to find out the chemical structure of the stone which has been passed. Further tests can be done by analyzing a 24-hour urine sample. Exact amounts of calcium, oxalate, uric acid and cystine can be measured. A stone may not pass on its own. It may get stuck in the ureter. When the stones are too small, sometimes abdominal CT scan may be advised.
Sometimes kidney stones are "silent". They are called so because they do not cause symptoms. Infact they are found on x rays taken during a general health exam. If they are small, these stones would likely pass out of the body unnoticed. But many a times there may be complications associated with it, e.g a ureteral stone might be associated with obstruction and upper UTI and this truly is a urologic emergency. So it is very important to consult a urologist. Let us see the treatments offered for renal calculi:
Ureteroscopic Stone Removal
Although some kidney stones in the ureters can be treated with ESWL (Read this technique below), ureteroscopy may be needed for mid- and lower-ureter stones. No incision is made in this procedure. Instead, the surgeon passes a small fiberoptic instrument called an ureteroscope through the urethra and bladder into the ureter. The surgeon then locates the stone and either removes it with a cage-like device or shatters it with a special instrument that produces a form of shock wave. A small tube or stent may be left in the ureter for a few days to help the lining of the ureter heal. Before fiber optics made ureteroscopy possible, physicians used a similar "blind basket" extraction method. But this outdated technique should not be used because it may damage the ureters.
FIGURE A: shows rigid scope which is inserted through the bladder to remove stones in the ureter.
FIGURE B: shows flexible scope which is inserted through the bladder and ureter into the kidney to remove small stones in the kidney.
Surgery should be reserved as an option for cases where other approaches have failed. Surgery may be needed to remove a kidney stone if it:
Percutaneous Nephrolithotomy is recommended when the stone is quite large or in a location that does not allow effective use of ESWL (read below). In this procedure, the surgeon makes a tiny incision in the back and creates a tunnel directly into the kidney. Using an instrument called a nephroscope, the surgeon locates and removes the stone. For large stones, some type of energy probe (ultrasonic or electrohydraulic) may be needed to break the stone into small pieces. Generally, patients stay in the hospital for several days and may have a small tube called a nephrostomy tube left in the kidney during the healing process.
Extracorporeal Shockwave Lithotripsy
Until 20 years ago, surgery was necessary to remove a stone. It was very painful and required a recovery time of 4 to 6 weeks. Today, treatment for these stones is greatly improved, and many options do not require major surgery.
There are several types of ESWL devices. In one device, the patient reclines in a water bath while the shock waves are transmitted. Other devices have a soft cushion on which the patient lies. Most devices use either x rays or ultrasound to help the surgeon pinpoint the stone during treatment. For most types of ESWL procedures, anesthesia is needed. In most cases, ESWL may be done on an outpatient basis. Recovery time is short, and most people can resume normal activities in a few days.
Aastha has obtained the first Lithotripsy machine in Mulund and surrounding suburbs. We have a separate Lithotripsy OT for the same.
Mechanical Percussion and Inversion (MPI)
While shockwave lithotripsy is a very effective treatment for kidney stones, it sometimes leaves fragments in the lower portion of the kidney. Gravity and certain technical features of kidney anatomy can trap these pieces so that they settle in the lower pole and do not pass. They can enlarge over time to form new kidney stones or infections.
A combination of mechanical percussion and inversion (or MPI) can eliminate the sand particles before they can cause problems. During this treatment, the patient is placed on a stretcher with the top half of the body angled towards the floor. A large vibrator called a percussor is held against the skin of your back over the kidney that contains the stone fragments. A diuretic is administered to increase the flow of urine. The combination of these three factors helps the sandy particles to pass out of the lower pole and out of the body before they can enlarge and cause problems.
To prevent cystine stones, you should drink enough water each day to dilute the concentration of cystine that escapes into the urine, which may be difficult. More than a gallon of water may be needed every 24 hours, and a third of that must be drunk during the night.
One advantage of percutaneous nephrolithotomy over ESWL is that the surgeon removes the stone fragments instead of relying on their natural passage from the kidney. But ESWL is gaining popularity these days because of the three main reasons:
Though there may are few drawbacks with ESWL. Most patients have blood in their urine for a few days after treatment. Bruising and minor discomfort in the back or abdomen from the shock waves are also common. To reduce the risk of complications, doctors usually tell patients to avoid taking aspirin and other drugs that affect blood clotting for several weeks before treatment. Sometimes the shattered stone particles cause discomfort as they pass through the urinary tract. In some cases, the doctor will insert a small tube called a stent through the bladder into the ureter to help the fragments pass. Sometimes the stone is not completely shattered with one treatment, and additional treatments may be needed. ESWL is not ideal for very large stones.
A simple and most important lifestyle change to prevent stones is to drink more liquids-water is best. Infact if a person has tendency to form stones, they must drink enough liquids throughout the day to produce at least 2 quarts of urine in every 24-hour period.
People who form calcium stones used to be told to avoid dairy products and other foods with high calcium content. But recent studies have shown that foods high in calcium, including dairy products, may help prevent calcium stones. Taking calcium in pill form, however, may increase the risk of developing stones. One may be told to avoid food with added vitamin D and certain types of antacids that have a calcium base. If you have very acidic urine, you may need to eat less meat, fish, and poultry. These foods increase the amount of acid in the urine.
The doctors will advice the patient to come for a regular follow ups. This is very important and should not be ignored.