The Other Causes of Kidney Stones

• Heredity. There is no consensus as to why kidney stones form.: Some people are more susceptible to forming kidney stones, and heredity certainly plays a role. The majority of kidney stones are made of calcium, and hyperuricemia (high levels of calcium in the urine), is a risk factor. The predisposition to high levels of calcium in the urine may be passed on from generation to generation. Some rare hereditary diseases also predispose some people to form kidney stones. Examples include people with renal tubular acidosis and people with problems metabolizing a variety of chemicals including cystine (an amino acid), oxalate, (a type of salt), and uric acid (as in gout).

• Geographical location: There is also a geographic predisposition in some people who form kidney stones. There are regional "stone belts," with people living in the Southern United States, having an increased risk. This is likely because of the hot climate, since these people can get dehydrated, and their urine becomes more concentrated, allowing chemicals to come in closer contact and begin forming the nidus of a stone.
• Diet: Diet may or may not be an issue. If a person is susceptible to forming stones, then foods high in calcium may increase the risk, however if a person isn't susceptible to forming stones, nothing in the diet will change that risk.
• OTC products: People taking diuretics (or "water pills") and those who consume excess calcium-containing antacids can increase the amount of calcium in their urine and increase their risk of forming stones. Patients with HIV/AIDS who take the medication indinavir (Crixivan) can form Indinavir stones.