Kidney stones can develop for various reasons: high calcium levels in the urine, high oxalate levels in the urine, bacterial infections, gout, a hereditary disease, the malabsorption of fat and even a high amount of vitamin C. People with kidney stones can experience blood in their urine, nausea, vomiting and pain.
Types of Kidney Stones
Kidney stones are a common disorder: Approximately 7 percent of American women and 13 percent of American men have this problem, according to John Asplin, M.D., and medical director of Litholink Corporation, in "Harrison's Principles of Internal Medicine." There are four kinds of kidney stones. Cystine stones form if someone has a genetic problem in which their kidneys cannot transport four amino acids, including cystine. Uric acid stones can form in those with high uric acid levels in the urine. Struvite stones can develop from a bacterial infection, and there are calcium stones.
Calcium Stones
Calcium oxalate and calcium phosphate stones are the most common kind of kidney stone. At least 75 percent of kidney stones are made of calcium, says Benjamin Parker, M.D., of the Division of Nephrology at the University of California, in "Pathophysiology of Disease." Most of the time, these stones develop because people have hypercalciuria, or high amounts of calcium in their urine. Crystals of calcium form, grow and come together to form a stone. Some people who have a high amount of uric acid in their urine form calcium stones instead of uric acid stones.
Calcium Stones and Vitamin C
Hyperoxaluria, or high amounts of oxalate in the urine, can lead to calcium stones. This can happen in people who have a problem absorbing fats because the excess fat will join to calcium, leaving high amounts of oxalate. Normally, calcium will join with oxalate. Very high amounts of vitamin C, not a lack of vitamin C, also can lead to calcium oxalate kidney stones because vitamin C can be changed to oxalate. This is more likely in people who have had kidney stones and is why, according to the National Institutes of Health, those who have had renal stones should not take more than 500 mg a day of vitamin C.
Symptoms and Diagnosis of Kidney Stones
A person with a kidney stone might have hematuria, or red blood cells in the urine. They might see red urine, or their urine might not look red but the lab detected the red blood cells. They can have nausea, vomiting and pain in their back or side. A diagnosis will include a urinalysis, or an examination of the urine by the lab, as explained in The Merck Manual for Healthcare Professionals by Glenn Preminger, M.D., director of the Comprehensive Kidney Stone Center. An ultrasound, X-ray or CT also might be conducted.
Types of Treatment
Dr. Preminger describes kidney stone treatment in The Merck Manual for Healthcare Professionals. It includes pain medications, and the physician might advise people to drink more fluids to help the kidney stones pass. There is medication available that might help the stones pass, but any stones that do not pass on their own within six weeks usually need to be removed. A surgeon can use a procedure called extracorporeal shock wave lithotripsy to break up the stones so that they become small enough to pass, or use an instrument called an endoscope.
References
- "Harrison's Principles of Internal Medicine"; Anthony Fauci, M.D., Dennis Kasper, M.D., Dan Longo, M.D. et al.; 2008
- National Institutes of Health: Diet for Kidney Stone Prevention
- "Pathophysiology of Disease: An Introduction to Clinical Medicine"; Stephen McPhee, M.D., Gary Hammer, M.D., Ph.D.; 2010
- The Merck Manual for Healthcare Professionals: Urinary Calculi
