Stones of the Kidney

Stones of the Kidney, Ureter and Bladder

Stones in the urinary tract are common. Often these do not produce symptoms and are detected accidentally. Some of the conditions causing stones are genetic in nature. Recurrence of these stones is common, although difficult to diagnose correctly but if not treated in time may lead to permanent damage to the kidney.

Recurrent stone disease should always be investigated thoroughly to find out the underlying cause.

Investigations Involve

Analysis of the stone if it has been passed spontaneously or removed surgically.

Urine routine examination to look for crystals of oxalates, uric acid, cystine or other salts.

Blood tests are done for levels of calcium, uric acid, oxalate, acid content, phosphorus, magnesium, parathormone levels etc. Kidney function also needs to be evaluated at the time.

X Rays are carried out to know whether the stones are radioopaque (seen on X Rays) or radiolucent (seen only on USG).

Urine tests are done to know specific gravity, acidity, calcium excretion, urate excretion, citrate excretion etc.

For urine tests, 24 hour collection of urine is collected in acidic and alkaline media and then analysed.

In most cases of recurrent stone formations, a cause can be found or excluded and a proper therapy is instituted.

Stone Disease of the Kidneys

Stone Disease of the Kidneys.

Stone formation in the kidneys is a common disease. About 1in 8 men and 1 in 20 women suffer from the symptomatic stone disease. Stone formation without symptoms is even more common.

About ¾ of the stones contain calcium and 10% have uric acid. Rest are due to combinations and rare diseases.

Calcium Stones

These contain calcium oxalate or calcium phosphate. Former is more common.

The risk factors for stone formation are

In Urine 

Low volume , High calcium in urine, high acid concentration and low citrate levels.

In Diet

Water and fluid intake is low, fruits are seldom eaten, food has high oxalate level or if calcium content of the diet is on the lower side.

Other diseases with high risk for stone formation are overweight, gout, diabetes, recurrent urinary tract infection etc. Bariatric surgery is a very significant risk factor.

If kidneys have certain diseases like the inability to excrete acid, a stone formation may occur.

Symptoms: Stones if they are in the urinary path (ureters or urethra) pain colicky in nature often radiating from back to lower abdomen or upto urine passage opening (urethra) may occur. This pain is at times very severe necessitating urgent consultation.

Urine may be passed in drops and is often red in colour due to blood.

If the passage of urine is blocked due to stone at any site, high pressure develops upstream of the blockage. If not treated early this may permanently damage the kidney.

In India, an untreated stone disease is a common cause of permanent renal failure.

Stone analysis, various urine tests aid in finding the underlying cause of stone formation. A cause is found in about ½ of the cases.


Stone disease can usually be prevented by adequate water intake, fruits or fruit product ingestion, enough calcium and lower salt in the diet and early complete treatment of urinary tract infection.

Eating lower oxalates in the diet is of questionable value.

Small stones pass spontaneously with more fluid ingestion and alpha blockers. Large stones need to be removed by surgery.