Kidney Stones
Kidney stone prevention and long-term care
Passing one stone is misfortune. Passing a second is usually preventable, and the workup that prevents it is straightforward.
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Why do kidney stones need a nephrologist?
Kidney stones are hard mineral deposits that form when certain substances in the urine become concentrated enough to crystallize and clump together. They are common, and without changes roughly half of people who form one stone form another within about ten years. A urologist manages a stone that is causing an acute blockage. Nephrology handles the other half of the problem: working out why stones are forming in your case, and reducing the chance of the next one.
Why do kidney stones keep coming back?
Stones are a symptom of urine chemistry, not a random event. Low fluid intake is the most common contributor, because concentrated urine gives crystals a chance to form. Beyond that, high urine calcium, low urine citrate, high oxalate, high uric acid, and unusually acidic or alkaline urine each push in the same direction, and most stone formers have more than one of these at once. Diet, climate and sweat losses, certain medications, gastrointestinal conditions, and inherited tendencies all feed into the picture.
What is a metabolic evaluation for kidney stones?
The single most useful test is a 24 hour urine collection, done at home, which measures volume along with the substances that drive stone formation. It is paired with blood work covering calcium, uric acid, kidney function, and electrolytes. If you have caught a stone, sending it for analysis is enormously helpful, because the stone type points directly at the treatment.
This evaluation is what turns generic advice into a specific plan. Two patients with the same symptoms can need almost opposite dietary changes depending on what their urine shows.
What kidney stone prevention actually works?
Fluid comes first, and the target is defined by output rather than intake: most stone formers are aiming to produce at least two to two and a half litres of urine a day, which usually means drinking noticeably more than that feels necessary.
- Reducing dietary sodium, which drives calcium into the urine
- Moderating animal protein intake rather than eliminating it
- Keeping normal dietary calcium, since restricting calcium raises stone risk instead of lowering it
- Limiting very high oxalate foods when the urine study shows high oxalate
- Adding citrate, through citrus or prescription potassium citrate, when urine citrate is low
- Thiazide diuretics for high urine calcium, or allopurinol for uric acid stones, where indicated
How does nephrology work with urology on stones?
A stone that is obstructing the urinary tract, causing uncontrolled pain, or accompanied by infection needs urologic treatment, and those referrals are made promptly. Prevention work then continues afterwards, which is the part that determines whether you are back in the same position in three years.
When should you ask for a nephrology referral?
Any of the following is a reasonable reason to be seen. If you are unsure, call the office and we will help you work out whether an appointment makes sense.
- A second stone, or a first stone at a young age
- A family history of kidney stones
- Stones on both sides, or several stones seen on imaging
- A stone that turned out to be uric acid, cystine, or struvite on analysis
- Stones alongside gout, inflammatory bowel disease, or previous bowel surgery
- Reduced kidney function in someone who forms stones
Common questions
- Should I cut calcium out of my diet to avoid stones?
- No. This is the most common misunderstanding about stone prevention. A low calcium diet increases the risk of calcium oxalate stones, because dietary calcium binds oxalate in the gut and stops it reaching the urine. Normal dietary calcium is protective; calcium supplements are a separate question worth discussing.
- How much water should I drink?
- Enough to produce at least two to two and a half litres of urine a day, which for most people means drinking somewhat more than that. Pale urine through the day is a reasonable everyday check.
- Do all kidney stones need surgery?
- No. Many smaller stones pass on their own with fluids and pain control. Procedures are reserved for stones that are obstructing, causing infection, too large to pass, or not moving after a reasonable period.
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This page is general education about a medical condition. It is not medical advice and is not a substitute for diagnosis or treatment by a qualified clinician. For guidance about your own kidney health, please speak with Dr. Baig or another licensed healthcare provider.