Kidney Stones – Causes, Diagnosis, Treatment and Prevention

Kidney stones or Renal Calculi is the common term for Nephrolitiasis, a sometimes extremely painful condition where a build up of calcium, oxalate and uric acid creates hard crystal structures which vary in size from very small to golf ball like.

The kidneys are two bean shaped structures which lie near the middle of the back just under the ribs. They are responsible for removing excess water and wastes from the blood, passing it out through the ureters as urine. They are also involved in maintaining the balance between sodium and potassium in the body and in the detoxification of the blood.

Kidney stones can form anywhere in the urinary tract, are mostly passed out without any problems but when they get stuck the pain is of an extraordinary intensity.

Kidney stones occur at least once in the lifetime of about 10% of the population, more often in women and the peak age is from 20 to 40. The incidence is higher in Caucasians and because of the higher likelihood of dehydration it is more common in hot climates.

Causes of Renal Calculi:

The exact cause is not known but predisposing factors include;

· Dehydration which causes a reduced urine production and allows the coagulation of substances that should be dissolved in the urine.

· Obstructions, particularly in immobilised patients in whom urination is often impaired allowing the solids to clump together.

· Infections which may well be the result of bacteria growing behind the initial obstruction.

· Metabolic factors such as gout, defective metabolism of oxalates, excessive intake of vitamin D and calcium and genetic defects.

· Bowel disease, Ileal bypasses or renal tube defects.

· Uric acid kidney stones which form when the uric acid level in the kidneys is higher than that in the blood.

Signs and Symptoms of Kidney Stones

Most renal calculi are small enough to pass through the ureters without any pain at all but when they get to a size where they obstruct the opening of the ureter they can cause intense pain of a level often compared to that of child birth. Typically the pain travels across the back and through the abdomen into the genital region varying in intensity as the peristaltic contractions in the ureters come and go. Sometimes the stones may be present in the renal pelvis and this may present as a dull pain which is more constant. When the pain is severe it may be accompanied by nausea, vomiting, abdominal distension, fever and blood in the urine.


Patient observation, x-rays, ultrasound, intravenous pyelograms, urinalysis MRI and CT scans are used alone or in combination to confirm diagnosis and to determine the size and location of the stones.

Treatment of Kidney Stones

Treatment is dependent on the size and location of the stones but in 90% of cases the stones are less than 5mm in diameter and can be allowed to pass naturally after increased fluid intake either by drinking or by the administration of an IV solution. Strong analgesics or other pain relief methods such as powerstrip pain patches need to be administered to control the pain and lessen the spasms. Sometimes a diuretic is added to promote urine flow and further calculus formation. Walking if possible should also be encouraged. Most stones will pass within 72 hours but for some it can take weeks.

Larger stones can be either broken up with a form of shock wave therapy called Lithotripsy or they can be manipulated and removed by introducing a cytoscope into the urethra.


Recent studies have shown that the restriction of dairy food which used to be advised is probably incorrect and that foods rich in calcium will actually help prevent kidney stones, however the impact of calcium supplements is not certain and it may pay to avoid them. Very recent research on Cell signaling molecules seems to indicate cell signaling supplements may well help to bring the body back into balance.

As with so many health problems, exercise is highly recommended because movement will help stones to mobilize. Adequate hydration is essential to prevent recurrence.