Kidney stones (medically nephrolithiasis or urolithiasis) arise from salts that bind water-insoluble compounds. The resulting crystals can cause various clinical pictures. Depending on the location of the stones one speaks of kidney stones or bladder stones. Kidney stones form in the kidney, bladder stones in the bladder. Kidney stones can also migrate through the ureters into the bladder and from there into the urethra. Very small kidney stones are also called kidney grits.
This is how kidney stones develop
Kidney stones consist of calcium oxalate urate (urate stones), calcium phosphate, magnesium ammonium phosphate (struvite or infectious stones), cystine or xanthine. Mixed forms are also possible. The components of these crystals are normally dissolved in the urine. Above a certain concentration, however, they form water-insoluble compounds. These usually crystallize in the renal pelvis or, more rarely, in the bladder. And from there, the kidney stones sometimes migrate through the urogenital tract.
Kidney stones and bladder stones may initially go unnoticed for a long time because they do not cause any discomfort. But if, for example, they migrate from the kidney into the bladder and into the urethra, they can get trapped there.
When the kidney stones are stuck in the ureters, bladder outlet, or urethra, they suddenly cause severe spasmodic, wavy, or stabbing pains in the lumbar region (renal colic). Most of the pain radiates on the unaffected side or in the lower abdomen. Sometimes they are accompanied by chills, nausea, vomiting, urgency or blood in the urine. Often, small stones are flushed out. They often cause a short stinging pain when urinating.
It becomes dangerous when a kidney stone is stuck in the ureter and prevents the urine from draining. The urine builds up in the kidneys and the renal pelvis expands. For example, bacteria easily migrate into the kidneys and cause infections, such as acute pyelitis. Typical symptom is the flank-tapping pain, in severe cases, fever and chills are added. If the bacteria enter the blood, there is a risk of life-threatening sepsis (blood poisoning).
Pyelonephritis by kidney stones
If the stones are too big for walking, they remain in the kidney and cause chronic renal pelvic inflammation. Often even such stones cause little discomfort. Chronic renal pelvic inflammation, however, can eventually lead to a contracted kidney.
If you have the slightest suspicion of kidney stones or pyelonephritis, so kidney pain or renal colic, you should go to the doctor. This is especially true when fever comes to it. In general, you should be examined if the urine is dark or reddish due to blood.
The causes of kidney stones are very different. Inheritance, urine composition, malformations in the kidney, too little exercise, metabolic disorders or even eating habits play a role. There are a number of different kidney stones.
- infection stones arise, for example, as a result of recurrent bacterial urinary tract infections. The bacteria in turn increase the pH of the urine (over 7), it becomes alkaline. Alkaline urine in turn promotes the formation of phosphate-containing rocks.
- Urate and uric acid stones: Acid urine (pH below 6) promotes the formation of urate or uric acid rocks. Urine is often acidified by gout as well as purine-containing foods (especially meat and sausage products and offal). These foods increase uric acid uric acid levels and urine pH drops. Even severe fasting, cancer or chemotherapy can increase the uric acid level and make the urine acid; thus promoting the formation of uric acid rocks.
- calcium oxalate are often diet-related. A high-milk diet increases the calcium concentration in the urine. The oxalic acid content in the urine increases when a lot of chocolate and cocoa products, spinach, beetroot or rhubarb are eaten. As a result, calcium oxalate stones are often produced. These kidney stones are also favored by a hyperparathyroidism.
- cystine stones Formed by a genetic disorder of the amino acid metabolism (cystinuria) leads to the formation of cystine, especially in children.
Common causes of kidney stones formation at a glance:
- Disorders of calcium metabolism
- Disorders of uric acid metabolism (see gout)
- too little fluid intake or too much fluid loss (especially excessive sweating or diarrhea in chronic bowel disease)
- wrong diet with too much protein, fat, calcium
- chronic urinary tract infections
- other diseases that impede urinary drainage and thereby lead to urinary stasis
- genetic causes
- Hyperfunction of the parathyroid gland
- Cancers, chemotherapy.
Clarity on the diagnosis Kidney stones usually provide the symptoms, urine test strips and a short ultrasound examination. Rarely, additional imaging techniques are needed to detect kidney stones.
The therapy of kidney stones is based primarily on the location of the kidney stones.
Rice grain or pea-sized kidney stones are usually treated with combination therapy. These include analgesic, anticonvulsant and flushing medications, heat, exercise (especially jumping and climbing stairs) and lots of fluids.
A dissolution of kidney stones (litholysis) is only possible with uric acid stones (urate stones) and cystine stones. For this purpose, the uric acid-lowering drug allopurinol is given and the urine alkalized with alkali citrates or sodium bicarbonate (target pH 6.2 to 6.8). In addition, the patient has to change his diet to keep uric acid uric acid levels as low as possible. When these three methods are combined, uric acid or cystine stones dissolve.
Drug therapy of large kidney stones
Larger kidney stones, which cause renal colic, often cause pain comparable in intensity to labor. Pain-relieving painkillers (such as oxycodone) are usually given for this pain. Also common is the treatment with non-steroidal anti-inflammatory drugs such as diclofenac, the anticonvulsant Butylscopulamin and the analgesic pyrazolone derivative metamizole.
Smash kidney stones and kidney stone surgery
Small kidney stones can be smashed during an outpatient endoscopy or removed with a medical sling if they are cheap.
Larger stones can be smashed by means of acoustic pressure waves (shock wave treatment or extracorporeal shockwave lithotrypsy, ESWL for short). In some cases, surgery is necessary to remove kidney stones.
Diet and kidney stones are closely related. Therefore, changing your diet can support the treatment of kidney stones and also help prevent kidney stones.
For uric acid stones a purinarme diet is recommended (ie avoid sausage and meat as well as the consumption of offal). Coffee, black tea and cocoa may continue to drink. The purines contained there are not converted to uric acid.
For calcium oxalate stones, it makes sense to limit the consumption of milk and dairy products (calcium) as well as chocolate, spinach, rhubarb and tomatoes (oxalate). But please no strict diets. This will increase the risk for certain types of kidney stones. Therefore, you should only use fasting under strict medical supervision, especially if you are prone to kidney stones.
For kidney stones, you should first drink a lot, so that kidney stones or kidney stones do not settle, but are rinsed out if possible. Herbal drops or dragees with horsetail, birch leaves or home-healers have a supporting effect.
Many patients find heat very beneficial for kidney stones. For example, you can simply take a hot water bottle.
Exercise helps with the removal of kidney stones. Jumping up and down stairs, even better stepping up and down individual steps, occasionally carry the kidney stone to the bladder and from there with the urine outside.
Herbal preparations against kidney stones
Significant successes in the treatment of kidney stones achieve herbal medications.
- Kidney stones have been reported to be disintegrated with the help of tea made from fresh labweed.
- A tea infusion of dandelion roots to facilitate the passage of stones over the bladder.
- Real cat-beard or orthosiphon relaxes the draining urinary vessels, have an anti-inflammatory and pain-relieving effect on outgoing stones.
The best prevention of kidney stones is enough to drink. Many people simply do not drink enough. This not only promotes the formation of kidney stones, but also at the expense of concentration and promotes fatigue. So: Drink at least 1.5 liters a day, better more. Particularly suitable are water, fruit or herbal teas and juice spritzers.
In addition, you should always treat urinary tract infections accordingly. The same applies to metabolic, hormonal, renal and gastrointestinal diseases - the diseases that increase the risk of kidney stones (see the section entitled Causes of Kidney Stones).
For recurring kidney stones, a metabolic study in a special urinary stone center is recommended. Your health insurance provider or your urologist will help you find a suitable practice or clinic in your area.