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What Are The Various Types of Kidney Stones?

Different Types of kidney stones are determined and classified according to their chemical compositions.  The chemical composition of kidney stones is influenced, to a large extent, by diet, lifestyle habits, and hereditary factors.

Kidney Stones

Once a patient has passed a kidney stone it is important that the stone to be analyzed, in order to determine its chemical composition.  This helps the physician to understand the deficiencies or conditions within the patient's body, which may have caused the stone to develop.


With this information, an appropriate course of treatment and prevention strategies (including diet) can be determined. In particular, diets that are designed to help prevent kidney stones should be uniquely formulated, and should take into account the type of kidney stone and other specific medical conditions affecting each patient.

Four Basic Types of Kidney Stones

Kidney stones can be made up of a variety of substances, but there are four (4) basic types.  They are:

  • Calcium stones, 

  • Struvite stones, 

  • Uric Acid stones, and

  • Cystine stones.

Calcium Stones

Calcium stones are the most common type of kidney stones.  Approximately 80% of all kidney stones are classified as calcium stones.  They are composed mainly of calcium oxalate or calcium phosphate.  These stones are often associated with elevated calcium levels in the blood and urine.  Over an extended period of time, excessive levels of calcium can lead to the formation of calcium stones.

High levels of calcium in the blood can be as a result of various health conditions.  These include parathyroidism (malfunction of the parathyroid glands, which control the metabolism of calcium and phosphorus), and multiple myeloma (bone cancer).  A diet heavy in refined carbohydrates (especially sugar), meat (especially red meat), and poultry are among the main contributing factor of calcium stones.

Another very important contributing factor is dehydration or insufficient fluid intake.  Inadequate intake of fluids (especially water) causes the urine to become concentrated, which increases the likelihood of kidney stones formation.

Struvite Stones

Struvite stones (also referred to as staghorn kidney stones) accounts for approximately 10% of all kidney stones.  These types of kidney stones are made up of magnesium and the waste products of ammonia.  This type of kidney stone is sometimes called infection stone since it is usually associated with patients who have had repeated cases of bacterial urinary tract infections.  Struvite stones also tend to occur more frequently in women than men.

The bacteria that cause urinary tract infection produce a substance, which makes the urine less acidic.  Urine that is less acidic is an indication that not enough acid is being excreted in the urine.  When the urine becomes less acidic, struvite is then able to settle and form stones.

Uric Acid Stones

These types of kidney stones only account for about 5% of all kidney stones.  Uric acid stones are caused by high concentrations of uric acid in the urine, and are often associated with gout.


Gout is a disorder caused by excess uric acid in the bloodstream, which is deposited in joints.  This causes inflammation and destruction of joints.

Uric acid stones are formed when bits of uric acid begin to bind together.  Over time, a solid mass develops resulting in the formation of uric acid stones.

Cystine Stones

Only about 2% of all kidney stones are cystine stones.  This type of kidney stone is usually caused by a condition known as cystinuria.  This condition is usually present at birth and affects the patient's ability to properly process amino acids.  This causes the formation of stones, composed of cystine (a type of amino acid), in the kidneys or bladder.


Most types of kidney stones can be prevented by proactively adopting an appropriate diet and healthy lifestyle habits.  Persons with a personal or family history of kidney stones should be aware of the type of kidney stone to which they are susceptible.  This helps with the formulation of appropriate measures (such as diet and exercises) that can assist in preventing recurrence.

The importance of adequate daily consumption of fluids should be noted.  Adequate fluid intake (especially water), on a daily basis, is a basic but very important measure that can help to prevent the formation of all types of kidney stones.

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