Kidney Stones
Kidney stones are among the most common conditions seen by urologists. Unfortunately, kidney stones can also be among the most painful. Not surprisingly, Los Angeles urologist Michael Safir, M.D. has seen his fair share of patients who have been afflicted by kidney stones. A well-known urologic surgeon with specialized training in nephrology (the study of the kidneys), Dr. Safir uses the most advanced techniques available for the diagnosis and treatment of kidney stones at his Beverly Hills and West Hills urology offices.
What are kidney stones?
Kidney stones, also known as renal calculi, are concretions formed from crystals that separate out of the urine. Originally dissolved salts, they precipitate out of the urine much like rock candy crystals precipitate out of supersaturated sugar water.
What is the cause of kidney stones?
There is no simple, generalized answer that explains why people get kidney stones. Some people may just be genetically more prone to developing them. Diet is certainly a factor, but a predisposition to form kidney stones is at the foundation of the problem. If you have certain inherited disorders such as polycystic kidney disease, you have a much higher chance of getting kidney stones. Understanding some of the better-known specific causes of kidney stones is easier if you understand the different types of kidney stones.
Different Types of Kidney Stones
There are many different kinds of kidney stones; they may form from a variety of substances found in the urine. They come in all shapes and sizes. When people speak about “urinary stones,” although this implies stones forming in any part of the urinary tract, most urinary stones are, in actuality kidney stones. A kidney stone may make its way from the kidney through the ureter, into the bladder, and eventually out of the body via the urethra. No matter where it ends up, it is still a kidney stone, not a bladder stone. Major types of kidney stones include:
Calcium stones (also called calcium oxalate stones) - The most common type of kidney stones, these are formed by two substances normally found in your body – calcium and oxalic acid. When they combine, they form an insoluble salt called calcium oxalate, which precipitates out of the urine, forming stones. The genetic tendency to produce either too much calcium or too much oxalate in the urine can cause this problem, and a low-oxalate diet may be prescribed.
Uric acid (or urate) stones - These stones are caused by uric acid overproduction, which is what happens if you have gout.
Cystine stones - Cystine is an amino acid that is a component of many proteins. Some people have a rare genetic disorder (called cystinuria) that prevents cystine from being reabsorbed back into the blood; instead, excess cystine gets concentrated in the urine, producing stones.
Struvite stones - Struvite stones have an important difference from the other major types of kidney stones: they are always associated with urinary tract infections (UTIs).