Minimally invasive treatment for kidney stones: ESWL
The urinary tract system consists of the kidneys, ureters, bladder, and urethra. The kidneys are two bean-shaped organs below the ribs in your back (area between ribs and hips) that are in charge of filtering blood and making urine. They are mainly responsible for keeping a stable balance of salts and substances in the blood by removing extra water and wastes from the blood to form urine. After urine is made, it is carried from the kidneys to the bladder via narrow tubes called ureters. The bladder then stores the urine until it is emptied outside the body through the urethra.
When crystals form in the urine, usually from build-up of excess chemicals that clump together, they are called kidney stones. There are several causes of stone formation, but the main one is dehydration (from not drinking enough water). Some stones may be as small as a grain of sand and pass on their own, while others can grow significantly larger and get stuck, causing obstruction (when a stone blocks the urine flow) that results in build-up of urine and swelling of the kidney(s). If this happens, you may develop symptoms and require interventions to prevent kidney damage.
Some stones may stay put in the kidney and never be a bother or they may pass out of the body without the need for intervention. Others can cause severe pain if they become trapped in one of the ureters (the narrow tubes that carry urine from the kidneys to the bladder). There are four types of kidney stones: Uric Acid Stones, Struvite Stones, Cystine Stones and Calcium Stones.
You may not have symptoms until the stone moves around your kidney or into your ureter. When symptoms develop, you may experience:
- Flank pain- sudden & intense pain in your back, often radiating to your abdomen and groin. The pain can fluctuate in intensity or come in waves.
- Frequency and/or pain when urinating
- Blood in your urine
- Cloudy or foul-smelling urine (if infection present)
- Nausea and/or vomiting
- Persistent urge to urinate
- Fever and chills if an infection is present (this may be an emergency if stone is blocking the ureter)
There is no definite or single cause of kidney stones, but there are several factors that may increase the risk of developing them.
- Dehydration- When you don’t have enough fluid in your body (usually from not drinking enough water). Your urine then becomes concentrated with crystal forming substances (such as oxalate, calcium, and uric acid) that stick together to form stones. Since there is not enough fluid in your urine to help dissolve the crystals, there is a greater chance stones will form.
- Similarly, or at the same time, your urine may be lacking the substances that prevent crystals from clumping together, creating a perfect environment for stones to form.
- High protein or high salt diet.
- Endocrine disorder, such as hyperparathyroidism, may increase the concentration of calcium in your urine and cause stones to form.
- Prostate enlargement or stricture disease can cause obstruction and development of stones.
- Gout can cause uric acid stones to form if not treated.
- Family or personal history - You may be more likely to develop stones if you or your family has had kidney stones.
- Adults over 40, although kidney stones may develop at any age.
- Being a man, although the number of women with stones is rising.
- Dehydration- Not drinking enough water or living in warmer climates increases your risk of stone formation.
- Inactive lifestyle or prolonged bed rest.
- Obesity- Large waist size and increased body mass index (BMI) has been linked to increase risk of kidney stones.
- Diets high in:
- Salt- Sodium pulls calcium into the urine, so when there is an excess amount of sodium in your urine, there is also excess calcium, putting you at an increased risk of forming stones
- Animal Protein- Too much protein in diet causes acid content in body to increase, causing the stone-preventing urinary substance (citrate) to be low. As a result, you are more prone to forming kidney stones.
- Oxalate- High intake of high oxalate foods, such as green leafy vegetables, nuts, tea, and chocolate may worsen situation.
- Medications- Certain diuretics or calcium-based antacids may increase risk of stone formation by increasing the amount of calcium in urine. Also calcium and vitamin C supplements are associated with kidney stones.
EVALUATION AND DIAGNOSTIC TESTS
When a kidney stone is suspected, in addition to a history and physical, the following tests or procedures may be performed:
- Urine tests: to check for infection, as some stones are associated with infection. A 24 hour urine collection may also help detect if too much stone-forming substances or too few stone-preventing minerals are excreted in your urine.
- Blood tests: to check and monitor your kidney function, as well as to see if there is too much calcium or uric acid in your blood stream.
- Imaging studies:
- X-ray- A plain film of your abdomen, also known as KUB (Kidney, Ureter, Bladder) to determine if the stone is visible.
- Ultrasound- A non-invasive scan to see if there are any obvious stone or blockage causing kidney swelling.
- CT scan- A series of plain films combined to form a picture of your body. It can identify size and location of stones to diagnose and determine the best course of treatment for you.
Treatment depends on the type of stone, the size, and the cause.
- For small stones with minimal or no symptoms, a conservative expectorant approach may be taken to allow to the stone to pass naturally. This wait-and-see approach may incorporate the following:
- Drinking plenty of water- At least 2 liters a day, unless told otherwise, to help flush out stone.
- Medical therapy- Medications may be prescribed to help pass stone and/or to help provide pain relief if needed.
- Observation with repeat tests and studies, if needed.
- For larger or symptomatic stones, a more invasive approach may be used to get rid of stones. These include:
- Extracorporal Shock Wave Lithotripsy (ESWL)- A procedure where a machine produces sound waves to create strong vibrations. These vibrations break up stones into tiny pieces that can pass in your urine.
- Ureteroscopy (URS) with or without laser lithotripsy (LL) - A procedure under local or general anesthesia where a special scope with camera passes through the urethra and into the ureter. Once the stone is identified, it is either removed or broken up into smaller pieces with special tools. A temporary tube (stent) may be placed at that time, to promote healing and decrease swelling. This stent should be removed within 1-3 weeks after procedure.
- Percutaneous nephrolithotomy (PCNL) - A surgery done under general anesthesia for very large stones. A small cut is made through your back and small cameras and tools are used to remove the stone(s).
A combination of lifestyle changes and medication may be used to prevent stones from recurring.
- Drink plenty of water throughout the day. At least 2-2.5 liters of water daily. You may need to drink more if you exercise often or live in warm/hot climates.
- Eat a balanced nutritional diet low in salt and animal protein. Fast food, canned food, frozen food, and luncheon meats are known to be high in sodium content. Avoid these and always look at your food labels. The daily portion of meat, chicken, or fish is the palm of your hand, don’t exceed that.
- Eat a normal amount of calcium-rich foods, but nothing in excess. Avoid calcium and vitamin C supplements, as these have been associated with increased risk of kidney stones.
- If possible eliminate sodas from your diet, particularly dark colas.
- Exercise and weight loss. A decrease in waist size can also help reduce the risk of stones.
- Other recommendations may be given depending on the type of stone you have.
- Based on type of stones you form, medication may be prescribed, especially if recurrent and persistent.
- Keep in mind that diet and lifestyle changes alone can significantly decrease your chances of producing kidney stones. This may avoid you being on medications for life.