Kidney Stones Types

A number of materials can form kidney stones, including calcium and uric acid. Kidney stones develop as minerals and other wastes accumulate, adding layers upon layers and eventually forming masses large enough to cause obstructions and other problems.

Kidney Stone Formation

Hard masses develop when waste materials are not dissolved adequately in urine. Microscopic crystals of waste material remain in the kidney. Over time, the crystals grow in size, until they are large enough to cause blockages or other kidney stone symptoms. These deposits are also called calculi (plural for calculus).

The most common elements of calculi are calcium, oxalate, phosphate and uric acid. Kidney stone formation occurs when excessive amounts of waste material accumulate and cannot be dissolved in the urine. Conversely, calcium and other materials may be present in normal amounts, but the body possesses insufficient water to process enough urine to dissolve them.

Certain substances that occur naturally in urine help break down and dissolve waste material, the most notable of these substances are citrate, magnesium and pyrophosphate. A deficiency of these substances can also promote the growth of stones.

Calcium Oxylate