Overview

The four main types of kidney stones are:

Calcium stones.

Most kidney stones are made of calcium compounds. Conditions that cause high calcium levels in the body, such as hyperparathyroidism, increase the risk of calcium stones.

Uric acid stones.

Some kidney stones are made of uric acid, a waste product in urine. You're more likely to have uric acid stones if you have:

• Low urine output.
• A diet high in animal protein, such as red meat.
• An increase in how much alcohol you drink.
• Gout.
• Inflammatory bowel disease.

Struvite stones.

Some kidney stones are struvite stones. These can be serious, because they are often large stones and may occur with an infection.

Cystine stones.

Stones made of a chemical called cystine are less common. They're more likely to occur in people who have a condition that results in too much cystine in the urine (cystinuria).