Small kidney stones and ureteral stones often come off by themselves. As long as they do not cause severe discomfort or complications, surgery is not necessary. Larger stones usually have to be treated. Depending on their location and size, they are then shattered or removed by endoscopic surgery.
Most stones with a diameter of less than 5 millimeters come off on their own, as do half of all stones between 5 and 10 millimeters. Such small stones are often excreted with the urine after one to two weeks.
If it is foreseeable that a stone will be flushed out by itself, one usually waits. If symptoms occur while the stone is moving through the ureter, painkillers such as ibuprofen or diclofenac can help.
Larger stones cause discomfort and usually have to be crushed or removed by surgery. This is necessary when
-a stone is not removed within four weeks,
-there are complications,
-severe colics occur or
-the stone is larger than 10 millimeters.
Uric acid stones can sometimes be dissolved by medication.
Do drugs help with kidney stones and ureteral stones?
Make elimination easier
Drugs from the group of alpha-blockers are supposed to facilitate the elimination of the stones. They relax the muscles in the lower part of the bladder. Alpha-blockers are drugs used to treat benign prostate enlargement. They are not approved for the treatment of kidney and ureteral stones. However, the alpha-blocker tamsulosin in particular is sometimes used off-label.
According to current research, alpha-blockers can support the elimination of stones. This is shown by an evaluation of 67 studies on urinary stones with a size of about 5 to 10 millimeters:
Without alpha-blockers, stones were eliminated in about 50 of 100 people within four weeks.
With alpha-blockers, the stones came off in about 73 out of 100 people within four weeks.
The therapy thus helped 23 out of 100 people to get rid of the stone.
Temporary side effects of alpha-blockers are low blood pressure, dizziness and fatigue. In a large study, 4 out of 100 people discontinued treatment because of such side effects. In 5 out of 100 men, the drugs also caused a temporary “dry ejaculation” (retrograde ejaculation). During this process, the seminal fluid is released into the bladder and not or hardly at all to the outside.
Uric acid stones dissolve
Uric acid stones are the only stones that can sometimes be dissolved with medication. Alkaline citrates or sodium carbonate, sometimes also allopurinol, can be used for this purpose. Alkali citrates and sodium carbonate raise the pH of the urine, allopurinol lowers the uric acid level. Drinking a lot supports the effect of the drugs: If more urine is made, the uric acid can dissolve better. In the case of a urinary tract infection, drug treatment of uric acid stones is not possible.
If the treatment is successful, it saves an operation to remove the stones. However, it is not clear how often uric acid stones can be dissolved with medication. So far, there are no sufficiently meaningful studies on this.
How are kidney stones and ureteral stones removed?
If stones are not excreted on their own, they are either crushed with shock waves or removed during a minor operation. Which method is most suitable depends mainly on the size, location and composition of the stones.
Shock wave therapy
In shock wave therapy the stones are crushed by sound waves. The debris is then discharged with the urine. The treatment is also known as extracorporeal shock wave lithotripsy (ESWL). A sound probe is placed on the skin, which sends sound waves through the tissue to the stones. For uncomplicated kidney stones, shock wave therapy takes about 30 to 60 minutes. It is often possible on an outpatient basis. The success of the treatment is checked with an ultrasound examination or an X-ray.
Shock wave therapy is particularly appropriate for kidney stones that are smaller than 20 millimeters. If the stones are located in the upper third of the ureter, they should not be larger than 10 millimeters.
Removal with an endoscopic procedure
If the urinary stones are removed by surgery, two methods are commonly used: the so-called ureterorenoscopy and percutaneous nephrolithotripsy.
Uretero-renoscopy : In this method, fine instruments are passed through the urethra and bladder with the help of an endoscope, up the ureter and into the stone. There the stone is crushed mechanically or by laser so that the debris can be excised or removed endoscopically.
The Uretero-renoscopy is used for urinary stones that are larger than 10 millimeters and are located in the middle or lower third of the ureter. Kidney stones up to 20 millimeters in diameter are also frequently removed by URS.
Percutaneous nephrolithotripsy (PCNL): In this method, the endoscope is inserted into the renal pelvis or kidney through a small incision in the back. There the stones are also crushed mechanically or by laser and then removed with small pliers. This method is mainly used for kidney stones with a diameter of 10 millimeters or more.Both procedures require a general anesthetic and a short stay in the hospital.
Today, major surgery is rarely necessary to remove kidney stones.
What are the advantages and disadvantages of different treatments?
For renal and ureteral stones, different treatments are possible depending on the situation. Studies have so far only compared to the following treatments.
Shock wave therapy and percutaneous nephrolithotripsy for kidney stones
Some small studies have tested shock wave therapy and percutaneous nephrolithotripsy. In comparison, endoscopic surgery was more successful than shock wave therapy. Three months after the treatment showed
After shock wave therapy, 44 out of 100 people were free of kidney stones.
After PCNL, 95 out of 100 people were free of kidney stones.
However, the chances of success of shock wave therapy also depend on the size, location and composition of the kidney stones: stones with a diameter of less than 10 millimeters are more easily shattered. With larger or harder stones this is less likely to happen. Stones in the lower part of the kidney can also be treated less well with shock wave therapy.
With shock wave therapy there is a risk that the stones remain too large and get stuck in the ureter on their way to the bladder. Then further treatment is necessary. Sometimes a small tube (a so-called ureteral stent) is inserted into the ureter as a preventive measure. It should ensure that the stone remains can drain off easily.
The shock waves can be painful. Therefore, painkillers are given before the treatment. The kidney tissue can also be damaged, which can lead to bleeding, for example. Serious complications and long-term consequential damage are rare, however.
A percutaneous nephrolithotripsy can also lead to bleeding. These can sometimes require a blood transfusion. Fever and wound infections can also occur after the operation. In rare cases, other organs may also be injured. A hospital stay of several days is also necessary.
As there are only a few small studies comparing these two treatments, the frequency of complications cannot be quantified well. However, shock wave therapy is generally considered to be the gentler treatment.
Shock wave therapy and ureterorenoscopy for ureteral stones
When kidney stones have migrated into the ureter, we speak of ureteral stones. These stones are usually treated with shock wave therapy or endoscopically via the bladder and ureter. Several studies have compared the success rates of these methods for ureteral stones. It has been shown that most stones can be successfully treated with shock wave therapy. However, the success rate is slightly higher with ureterorenoscopy:
78 out of 100 people were free of ureteral calculi after shock wave therapy.
93 out of 100 persons were free of ureteral calculi after endoscopic treatment.
After shock wave therapy a second operation is therefore more often necessary.
The advantage of shock wave therapy is that it leads to complications less frequently than URS: complications occurred after 19 of 100 endoscopic interventions, but only after 10 of 100 shock wave therapies.
Possible complications of ureterorenoscopy are bleeding and urinary tract infections. The urethra can also be injured. However, serious complications are rare overall.
Supporting treatments such as a ureteral splint or a temporary artificial kidney outlet were also much less frequently necessary after shock wave therapy. However, pain occurred more frequently during and after treatment. In addition, post-operative bleeding and infections seem to occur more often after shock wave therapy.