Renal calculi, also known as kidney stones, are hard deposits of minerals and salts that form within the kidneys or urinary tract. They can range in size from a grain of sand to a golf ball, and can cause severe pain when they pass through the urinary tract.
Calcium oxalate is the most common type of kidney stone, but other types can also form, including struvite, uric acid, and cystine stones. Risk factors for developing kidney stones include dehydration, a diet high in certain types of foods, a family history of kidney stones, certain medical conditions, and certain medications.
Symptoms of kidney stones may include severe pain in the back, side, or lower abdomen, pain during urination, blood in the urine, nausea and vomiting, and frequent urination. Treatment may include medications to manage pain and nausea, drinking plenty of fluids to help pass the stone, and in some cases, surgical intervention to remove the stone.
Preventative measures to reduce the risk of kidney stones include drinking plenty of water, reducing salt and animal protein in the diet, and avoiding foods high in oxalates, such as spinach, chocolate, and nuts. In some cases, medications may be prescribed to help prevent the formation of kidney stones.