# What are kidney stones and what are their main types? Canonical page: https://clinicsjo.com/en/faq/what-are-kidney-stones-and-their-main-types Language: en Category: kidney Publisher: ClinicsJo Published: 2026-09-13T08:09:52.253Z Content updated: 2026-09-13T08:09:52.253Z Translation (ar): https://clinicsjo.com/ar/faq/what-are-kidney-stones-and-their-main-types Kidney stones are hard, pebble-like pieces that form in one or both kidneys. These stones develop when levels of certain minerals in the urine become high, causing them to clump together and harden. They can be as small as a grain of sand or as large as a pea, and in rare cases, they can reach the size of a golf ball. Typically, small stones pass through the urinary tract without medical assistance or with minimal pain, but larger stones may become lodged in the urinary tract, causing an obstruction in urine flow and severe pain or bleeding. It is important to seek immediate medical attention if symptoms such as severe pain or bleeding appear to prevent complications like urinary tract infections or loss of kidney function. ## The Main Types of Kidney Stones Treatment options for kidney stones typically depend on their size, location, and composition. There are four main types of kidney stones: - **Calcium stones:** Calcium stones, including calcium oxalate and calcium phosphate, are the most common. The calcium found in food does not increase the chances of developing calcium oxalate stones. Typically, excess calcium that is not used by the bones and muscles goes to the kidneys and is flushed out with urine. When this does not happen, the calcium remains in the kidneys and combines with other waste products to form kidney stones [\[2\]](). - **Uric acid stones:** Uric acid stones may form when the urine contains excess acidity. Consuming large amounts of fish, shellfish, and meat, especially organ meats, can increase uric acid in the urine [\[2\]](). - **Struvite stones:** Struvite stones may form after a urinary tract infection. These stones can develop suddenly and grow large quickly [\[2\]](). - **Cystine stones:** Cystine stones result from a hereditary disorder called cystinuria, which causes the amino acid cystine to leak through the kidneys into the urine [\[2\]](). ## The Importance of Identifying Stone Type Identifying the type of kidney stone helps in developing an effective treatment and prevention plan. For example, treating uric acid stones may require dietary changes to reduce urine acidity, while struvite stones may require treatment for the underlying infection. A urinalysis can help identify the presence and type of crystals, providing an indication of the likely stone type [\[3\]](). If you are experiencing symptoms of kidney stones, early diagnosis and identification of the stone type can reduce the risk of serious complications. ## When Should You Seek Emergency Care? Although many kidney stones pass on their own, some symptoms require immediate medical help. These symptoms include severe pain in the back or side that does not go away, blood in the urine, fever and chills, vomiting, foul-smelling or cloudy urine, or a burning sensation when urinating [\[1\]](). These signs may indicate that the stone is stuck and causing an obstruction or infection, which requires urgent medical intervention to prevent kidney damage or other complications. For additional information on kidney stones, including causes, symptoms, treatment, and prevention, you can visit [Kidney Stones: Causes, Symptoms, Treatment, and Prevention (Arabic)](). ## Medical references - [Kidney Stones]() - [Definition & Facts for Kidney Stones]() - [Crystals in Urine]() General health education; not a substitute for individualized clinical assessment. Citation URL: https://clinicsjo.com/en/faq/what-are-kidney-stones-and-their-main-types#answer