The urinal stone formation is the most frequent urological disease. The rate of stone-patients at the urology wards is about 10-15%. Both the eating habits and genetic factors can play role in stone formation.

Process of stone formation

We do not know the mechanism of stone formation in all details as there is no a single reason, which could explain formation of all type stones. Until now it was managed to identify more than 30 crystalloid compounds in human urinal stones, but in most cases 8-10 compounds are present. More stone-forming factor can be present at the same time, e.g. more acidic urine, increased uric acid discharge in the congestive bladder causes stone consisting of uric acid.

Lithopedion formation:

The final composition of urine is formed in the collecting tract, but stone-formation was also observed in the upper part of nephorn. The "higher" the crystals are formed in the ureter the high is the super saturation, the high is the risk of stone-formation. The most important step of lithopedon formation is enacted in the renal papilla and/or on the surface of it.

Fixation of lithopedion:

The fixation of lithopedions suitable for growing to stone can be understood easily, if the nucleator (matrix, clump, aspiration) is so big that it can not leave the urinary channel, and also the microscopic crystals generated on it.

The frequent stones:

The stones can be categorized by different aspects (place of formation, residential place, chemical constitution, growth rate, size, shape, hardness, transmits or not X-ray, first or repetitive, single side or double side). According to the formation place its denomination can be identical with the name of residential place's name (parenchuma-stone, papilla-stone, calyceal-stone, diverticulum-stone, pyleum or renal pelvis stone, uruter-stone, bladder and urinary channel stone). The weight of urinary stones can be from 10 mg up to 1 kg. The biggest stones were found in bladder.

Calcium-oxalate-monohydrate (whewellit). It grows most frequently by fixing on papilla. These have generally dark-brown colour. The surface is slick, thus the probability of discharge of stones smaller than 5 mm is very high. The compact, radial and banded versions are counted as hardest. These can be broken up not easily, they regenerate after years. Whewellit is the most common urinal stone: in 40-50 case of 100 stones this is the main component.

Calcium-oxalate-dihydrate (weddellit) is the second common stone. These are also at sight crystalline, their surface is covered by randomly placed, colourless, 0,2-5 mm size, hard, rigid, sharp and picky crystals, therefore these are tending to inclusion, spontaneous discharge is sustained, causing bloody urine. These are growing fast, even in a year it can recrudesce. The modern, motionless life-style, plentiful feeding is contributing to the generation of these.

Calcium-phosphates (whitlockit, apatites). These substances form rarely stone, these are more frequent in mixtures or as collateral materials. These produce the strongest shade on native X-ray pictures. These forms in case of normal urine - above pH 6. Their colour is white in urinal channels, they are soft, fragile (in prostates stones brown and hard).

Magnesium-ammonium-phosphate-hexahydrate (struvit). Fast growing and big size forming stones (e.g. coral stones). Inside these could be even white, outside these are generally drab, ochreous, sometimes brownish. These are soft, cretaceous, well fragmentable. Pure struvit are to be observed generally at the arm-ends of coral stone's beaker. In case of such stone we shall always consider a ground disease with metabolism malfunction (e.g. hyperparathyreoidismus, hypercystinuiry).

Uric acid, uric acid dihydrate. Their characteristic ochreaous or brick red colour is originating from bounded urine pigments. The stones consisting of anhydrous uric acid have lamellar structure, are concentrated, very hard, especially ones generated in bladder. The difficulty of shock-wave fragmentation of these is very near to whewellites. Uric acid dehydrate stones are drab, consisting of crystals grown loose together, are easily fragmentable. These produces light shade on native X-ray pictures, therefore these type of stones are called X-ray negative. These are coprecipitating from urine more acid as average. Generally these are formed in males above 50 years, having picnic figure. As main part is uric acid in 5 % of stones.

Ammonium -hydrogen -urate and sodium-hydrogen-urate-monohydrate: Belongs to rare stones. Salt containing ammonia can generated as an effect of urease, furthermore because of e.g. phlogistic psilosis, laxativumabusus.

L-cystine: Rare stones (1%), ochreous, transparent, laureate-like stones. Relatively frequent in children. If generated parallel then their repeated occurrence can be expected. They grow fast and big, forming also coral stones. They are not very hard, but in spite of this resist quite well to shock wave.

Stone analysis:

Beyond urological examinations the reasons of stone formation can be determined based on chemical constitution, morphology of stones, localisation of components and substances of stone-weed. The detailed stone analysis helps not only in determination of stone formation, but also the selection of therapy and follow-up of it. The kidney stone alone does not mean illness.


The symptoms caused by kidney stones depend on location, size and mobility of stones. The stones resting in the parenchyma do not cause any symptom or occlusion, occasionally blunt waist-pain can occur.

Symptoms: pain, bloody urine, mattery urine, stone discharge, anuria

Blunt pains: The bigger stones, which quite do not move in the well-system, are causing indefinite, blunt pains in waist area. These pains could be increased for movement, overstrain.

Bloody urines: The volume of blood is not significant; in general there is no strong bleeding. The presence of it is for stone, but the lack of it does not mean that there is no stone in the urine collecting and/or discharge system.

Mattery urine: Existing infection beside the stone can cause it.

Stone discharges: frequent sharp urine is caused sometimes by urinary sand, urinary groat discharge.

Anuria: it can be recognized if the stones cause occlusion at both side simultaneously.

Examination of nephritic patients
  • Physical examination
  • Microscopic analysis of urine
  • Blood test
  • Body temperature-rise, fever
  • Ultrasonic examination
  • Native X-ray picture
  • Selection urography
  • Retrograde pyelography
  • Isotoperenography

Treatment: Conservative or operative

With the conservative treatment our aim is to eliminate the pain spasms and facilitate the discharge of stones (2-3 mm) kept suitable for discharge. The elimination of spasm can be attempted by giving antispasmodic (e.g. algopyrine) and hematoxylin-eosin antispasmodic medicines (No-Spa) in combination, which could complete with plentiful drinking, warm bath. The extracorporeal shock wave lithotripsy is minimal an invasive treatment (ESWL = Extracorporel Shock Wave Lithotripsy). The desired result can be achieved in case of stones less than 2cm of material calcium-oxalate-dihydrate, struvit + carbonate-apatite, of stones less than 1 cm of material calcium-oxalate-monohydrate, uric acid, cystine. The stone brakes up but not in all cases can be discharged. The duration of treatment is 45-60 minutes, during what the stone gets 3500-4000 shock waves. There could be need for more treatment in order to break up the stone totally. The treatment does not need causing wound to the patient.

Percutan nephrolithotomia (PCNL) method was introduced in Hungary by Csaba Tóth in 1984 for removal of stones, tumours, stenosises and or nerve-cells of kidney and ureter. The stones having a size greater than 1 cm are broken intrarenal by the breaking-boogie introduced via the nephroscope controlling the operation visually, both as monotherapy and combined with ESWL. The targeting channel could be broaden also via a cm-wide acusection on the skin until the well-system, by the equipment introduced into the channel, and the stone can be taken out. This causes wound to the patient. It is contra-indicated at patients having untreated blood coagulation malfunction. In case of having kidney stones both side first that stone is taken out, which kidney is higher endangered by the stone or which is having better function. Also in case of children can be applied the percutan stone removal and the intrarenal stone break up.

Essence of the operation:

The patient shall be examined and prepared as for surgical operation. The anaesthesia may be lumbar or local anaesthesia. If the kidney stone is less than 1 centimetre diameter, it can be tackled by forceps and removed. It the kidney stone is larger than 1 cm, then by energy transmitter introduced via work canal of nephroscop the stone will be broken into small pieces that can removed by forceps or by sucking.

The operation is finished by installation of nephrostomic drain. The nephroscop can be easily introduced into the upper part of distended ureter without damage The stone suspended in the middle part or lower part of ureter can be collected into the Dormina -bascet introduced through the nephroscop and removed in such way. The complication can be perforation, bleeding or damage of neighbouring organ. The percutaneous nephrolithotomy is complemented some times with insection of narrow calyx stem, and the expansion of ureter, and pipe is installed from the renal pelvis into the atmosphere.

This endocalicotomy (ECT) is always performed if the calyx stem containing the stone is very narrow. The nephrostomic drain is removed after 6 weeks. Percutaneous nephrostomy (PNS). Slack urine is removed from kidney cavern by a Percutaneous installed plastic pipe. This is a paliative surgical intervention. For solving the pyeloureteral passage or blockage of ureter not always the PNS is selected as first method. A retrograde installed uretercatheter , or a double -J- stent can also remove the slack urine, but precondition of this methode is that the uretercatheter shall be slide beside the barrier causing blockage up to the renal pelvis.

Dissolution of stones:

The anhydrous lithic acid stone and lithic acid hydrate can be dissolved by alcalisation of urine if the urine is not infected, and if the surface of stone is not covered by phosphate layer. Firstly in Hungary Dezső Frang performed succesful dissolution of stones.


The kidney stons can be renewed again after removal or leaving. All kind of kidney stones must be analysed for determination of their chemical composition. By knowing the chemical composition of stones we can use specific methods for prevention of stone formation.

General rules:
  1. Abundant intake of liquid (approximately 2 litres per day)
  2. more body exercise
  3. prevention of exsiccation of organism
  4. medication treatment of diapyesis in ureter (tooth, tonsilla, prostata, bladder, renal pelvis)
  5. formation of manner of life without stress
  6. anatomical coarctation
  7. ingestion of Rowatinex can be advised for facilitating motility of ureter and renal pelvis

Prevention of lithic acid stone formation:

By regular ingestion of citrate mixtures the pH value of urine shall be maintained between 6.2 - 6.8. Abundant intake of liquide shall be ensured, and diluted fruit tee or juice is also beneficial. Among meat types game, inmeatswhich are rich in purine are not advised. Poultry and fish can be consumed moderately. Nutrition by potato, cauliflower and culinary plants is advisable.

Prevention of calcium-oxalate stone:

magnesium-, potassium-, sodium-, citrate, atrophin, hypothaizid, sedativum, vitamin B - can be given as intermixture. It is advised to moderate consumption of food containing lot of calcium (milk, cottage-cheese) as well as food containing oxalate (rumex, spinach, rheum, cocoa, chocolate. Consumption of tomato, pumpkin, mushroom and lean meat, fish will be useful.

Prevention of Struvit + carbonate-, apatite stones formation:

Treatment against urea-demolisher bacteria, which are responsible for stone formation in alkaline urine shall be applied. We cannot prevent it efficiently by diet, but it is advisable to moderate consumption of food, which are influencing the pH value of urine into alkaline direction (such as milk, dairy products, culinary plants).

Prevention of Cystine stone formation:

Main emphasis is on abundant intake of liquid, ensuring the daily urine quantity of 3 litres (during 24 hours) and uniform diluted urine production shall be ensured also at night.

Fruit juices, soups, alkaline mineral waters, different types of tee, water are advisable daily in different variations. By increasing the pH of urine above 8 the solubility of cystine can be increased, but at the same time the danger of precipitation of calcium-phosphate increases. It is advisable to moderate consumption of such foods as lean meat, chicken, fish, milk, cheese, egg, bean, lentil, rice, cacao, cabbage, cauliflower, Brussels sprouts. Advisable consumption of mushroom, cow head meet, pig tongue root, pig lung, pease, earth-nut, nut, butter, oil, apple, banana, melon, china-orange, peach, apricot, plum, grape.
Resource: Prof. dr. Berényi Mihály - Az Urológia tankönyve