Kidney stones are small hard stones that form in the kidney because of backlog compounds, usually caclium, in the claret. Kidney stones occur in nigh v% of the population and are ordinarily fabricated of calcium. Hyperparathyroidism is the number one cause of kidney stones. Every person with a kidney rock should exist tested for a problem with their parathyroid glands. Almost half of all people with kidney stones have a parathyroid tumor in their neck that must be removed or the kidney stones will return. Learn what kidney stones are and what you should exercise to prevent them from coming back. Almost doctors exercise not practice the correct testing of parathyroid glands in patients with kidney stones.

What Causes Kidney Stones?

Kidney stones develop because the kidney is cleaning and filtering the blood of impurities. If you have also much of certain elements in your blood, the kidney will try to right it and remove the impurities which tin can collect to form stones if present in high amounts. By far the number i impurity in the claret that the kidney wants to get rid of is excess blood calcium. When at that place is too much calcium (or other minerals) in the blood, the kidney tries to remove it causing it to collect in the center of the kidney where information technology clumps together into one or more small stones. It is possible that the stones actually form in the bladder, but almost ever, kidney stones form in the kidney (thus their name!). And yes, kidney stones they really do look similar small stones.

What are Kidney Stones Made of?

At to the lowest degree ninety% of kidney stones are made upwardly of calcium and the number one cause of kidney stones is hyperparathyroidism, a disease caused by a problem with the parathyroid glands. The other 10% of kidney stones are made up of other blood impurities such as uric acid, and other very rare compounds. Kidney stones are discussed on this website because most are fabricated of calcium and the amount of calcium in our bodies is controlled by the parathyroid glands. It is the task of the parathyroid glands to command the amount of calcium in our claret and in our bones. However, about 2 per centum of people will develop a problem with their parathyroid glands during their lifetime (this entire website is about parathyroid problems), and all patients with a parathyroid problem will accept bug with calcium. Thus, by far the virtually common crusade for kidney stones is hyperparathyroidism--a disease of calcium acquired by a tumor on one or ii of the parathyroid glands. Nonetheless, this statement is merely true for people who just started having kidney stones, not people who have had many stones for many years.

Kidney stones occur in all people world wide at the aforementioned rate: between iii and 5% of the population. However, in our patients that we operate on for hyperparathyroidism, 38% of men have stones and 20% of women have stones. Thus not everybody with a parathyroid problem will get kidney stones (but they do get other problems!). And as well, not everybody with kidney stones has a parathyroid problem. All the same, if yous are reading this page because you recently had a kidney stone, you lot MUST exist checked for a parathyroid problem (we volition tell you how to do this later on this page). Untreated hyperparathyroidism doesn't just cause kidney stones, it likewise causes high blood pressure, osteoporosis, fractures, coronary centre disease, atrial fibrillation (middle problems), stroke, renal failure, GERD, and even increases your risk of several cancers. Avoiding more kidney stones is but one small function of why you must exist checked for hyperparathyroidism if you have kidney stones. IMPORTANT... practice not assume that your doctor is automatically checking you lot for a parathyroid trouble. Less than 20% of doctors (including urologists) cheque patients for parathyroid bug when they go a kidney rock. Then keep reading and make sure you are getting checked correctly. I important fact that must be stated: people with kidney stones due to parathyroid tumors usually don't take lots of kidney stones for many years. Instead, they have one or a couple of stones and they never had them before. This page is written for people who have a new onset of kidney stones, not people who have had dozens of stones for dozens of years. We volition talk over this at the bottom of the page.

4 Types of Kidney Stones

In that location are 4 different kind of kidney stones, shown in the tabular array beneath. The get-go two, however, are both generically chosen "calcium kidney stones" and they differ simply in the kind of other mineral that is combined with the calcium. It is not of import for y'all (or your doctor) to distinguish between the two types of calcium kidney stones. They behave the same, the treatment is the same, and they are both acquired by a parathyroid problem about half of the time.

Kidney Stone Blazon Percentage of all Stones Caused by Hyperparathyroidism ?
Calcium Oxalate kidney stones 85% Aye, about one-half of them
Calcium Phosphate kidney stones viii-10% Yes, at least 80% of them
Uric Acid kidney stones 5% No
Struvite kidney stones 2-3% No
Cystine kidney stones very rare, <0.01% No

As you can see, almost 95% of people with a kidney stone have a calcium-containing kidney stone. Some of them will accept parathyroid disease. Thus, everybody with a kidney rock must exist checked for an underlying parathyroid problem and so it can exist addressed. Information technology is likewise very of import for you to understand that you and your doctor may non know what kind of rock y'all had. Unless you take hold of it (or they remove it during surgery), nobody volition e'er know. Thus, if you lot don't know what kind of kidney stone you had, then it must exist assumed that yous had a calcium-kidney rock because 95% of stones are calcium stones. Therefore you should expect that you be checked for hyperparathyroidism (they should too bank check for claret levels of uric acid to check for uric acid stones, but that is less than five% of stones). The stones occurring with struvite are due to long-term bladder infections so that doesn't get confused with calcium stones, and cystine stones are a genetic trouble that is far besides rare to be discussed here.

Why Did You Get Kidney Stones?

If y'all accept kidney stones, y'all should check your blood calcium level. If your calcium level is high, then you need to get a PTH level checked. Note: The post-obit table and this web folio is written for people with NEW ONSET of kidney stones, not people who have had lots of stones for many years.

Claret calcium and parathyroid hormone (PTH) levels:
Did a bad parathyroid gland cause the Kidney Stones?

Blood Calcium Level Parathyroid Hormone PTH
(normal range xv-65 pg/ml) 		Acquired the Kidney Stone ? Grouping
United States
mg/dl		 Canada / Europe mmol/l
9.0 - 10.0 2.25 - ii.50  several 35 or below No 1
9.0 - 10.0 two.25 - 2.50 several 35 to 80 Unlikely 2
9.0 - 10.0 2.25 - ii.l several lxxx to 100 Unlikely iii
ix.0 - ten.0 2.25 - 2.50 several 90 or above Possible - check over again four
9.5 - 10.5 2.37 - 2.62 several 35 to 80 Probably- check again 5
10.four - xi.0 2.58 - 2.75 45 or above Yes 6
10.0 - 10.seven 2.25 - two.67 55 or above Yes 7
11.0 or above 2.75 or in a higher place 35 or above Aye 8

Note, to understand this table, you need to know that i normal blood calcium level means nothing. Nigh e'er yous are going to need at least two calcium and ii PTH levels. If the blood calcium level is normal, than it must be checked over again (because calcium levels go up and downwardly all the fourth dimension in people with a parathyroid tumor). Thus, the first cavalcade is for people who got their blood calcium checked more than one time and information technology was NORMAL, and so they got it checked a second time and it was higher. The showtime cavalcade is for people who had their calcium checked several times. If you had ane calcium level and it was high, then you are very close to having the reply---yes, the rock was caused by a parathyroid tumor. Near always, one loftier calcium level in a patient with RECENT onset of kidney stones is almost always due to a parathyroid tumor. Remember, the upper limit of normal blood calcium in adults over age 35 is 10.0 mg/dl (2.5 mmol/l). Many labs practice not report blood calcium normal ranges according to the patients age, instead showing an upper limit of normal of 10.5 (ii.62 mmol/l) which is the upper limit of normal for teenagers. We have an entire page dedicated to the normal range of calcium according to age. Teenagers and twenty-somethings have blood calcium levels that are higher than adults over 35. A calcium level of 10.5 mg/dl is perfectly normal in a teenager, only it is not normal in an adult over 35 years old.

Most people with kidney stones will be in Groups 1, 6, 7, and 8:

  • Grouping 1: multiple normal calcium levels and mutiple parathyroid hormone levels less than 35, it is very unlikely that they have a parathyroid tumor causing their kidney stones.
  • Grouping 6: multiple calcium levels, some in the nine's and some in the 10's, several parathyroid hormone levels above 45. This is a very commonly missed parathyroid/kidney stone group and these patients are overlooked all the time until they become a second or third bout of kidney stones and showtime needing operations for kidney stones.
  • Group 7: multiple calcium levels that are high normal or loftier, parathyroid hormone levels above 55. This group is too commonly ignored by their doctors until they go a second or tertiary tour of stones. Then everybody is kick themselves in the butt for missing the obvious parathyroid tumor that should have been removed years earlier.
  • Group 8: blood calcium levels above xi.0 mg/dl and PTH levels to a higher place 35. This should be very easy for any doctor to know, although the "normal" PTH level confuses many doctors. When the calcium is ever high, the PTH shouldn't be "normal", information technology should be low. Fifty-fifty if the PTH levels are not checked, claret calcium levels of 11.0 mg/dl and a kidney stone means primary hyperparathyroidism virtually 100% of the fourth dimension.

Also annotation that this kidney stone/parathyroid table has a different normal range for blood calcium levels in the The states compared to almost other countries. This is considering the US measures calcium in different units than virtually other countries. This is like measuring distance in miles or kilometers. It doesn't affair; it is nonetheless measuring distance, or in the case of calcium, the concentration of calcium in the blood. Always get a copy of your lab results: the units are always correct on the written report.

Measuring just claret calcium may not exist plenty
to rule out hyperparathyroidism as cause of kidney stones.

Many doctors will not measure parathyroid hormone levels to check to run across if y'all have a parathyroid tumor equally the cause of the kidney stones. They will see that your calcium "is normal", or "just a little fleck high" and presume (incorrectly) that a parathyroid tumor is non the crusade of the kidney stones. For these reasons, measuring blood calcium lone is not adequate to determine if a patient with stones has hyperparathyroidism or non:

  1. Calcium levels in patients with main hyperparathyroidism are variable. Most people with a parathyroid tumor (which must be removed)have calcium levels that go up and down, high sometimes and normal occasionally. Thus, if your doctor measures your calcium one fourth dimension after a kidney rock and says "your calcium was normal, so you don't have a parathyroid tumor as the cause" you may want to check that calcium over again. You cannot determine if somebody has a parathyroid tumor by measuring One blood calcium level. If the calcium is high, then cool--we figure it out. If the calcium is normal, then that doesn't hateful a thing, it must exist measured again, and the PTH must be measured.  Said differently: ane high calcium and new onset of kidney stones--> its hyperparathyroidism. One normal blood calcium and new onset of kidney stones--> we don't know and boosted calcium levels must be measured and parathyroid hormone (PTH) levels must be measured.
  2. Labs exercise not report claret calcium normal ranges co-ordinate to the patient's age. We have an unabridged page on this topic, simply the bottom line is that it is almost never normal for adults over age 35 to have blood calcium levels over x.0 mg/dl (2.5 mmol/l in Canada and Europe). If you lot have blood calcium levels of ten.0 mg/dl or higher and you accept a kidney rock, you accept greater than 90% hazard that you have a parathyroid tumor equally the cause. The trouble is that most labs will report a normal range of 10.five mg/dl (two.62 mmol/l) which is normal for teenagers, only not normal for adults over age 35. Be conscientious of the normal range on your labs! Adults should have calcium levels "in the 9's". We have a Hypercalcemia Calculator, that volition tell you the exact normal range of claret calcium for yous. Attempt it!

Kidney Stones and Hyperparathyroidism

Kidney stones occur in about iv% of people, but are much more common in people with blood calcium levels over 10.0 mg/dl (the upper limit of normal for adults over age 35). It is VERY of import to understand that the chances of getting kidney stones are Non higher if your blood calcium goes higher. Said differently, a calcium of 12 does non give yous college chances of getting kidney stones than a calcium of 11.  Many doctors don't understand this and say "your calcium isn't that high, we can but lookout man it for at present until information technology gets higher". That presumes that a very high calcium level is more dangerous than a mildly elevated calcium level--and it is not. Very mild elevations of blood calcium are just equally dangerous every bit very high elevations of calcium. The graph below is from eighteen,700 of our patients that we operated on for primary hyperparathyroidism. It shows the occurrence of kidney stones co-ordinate to how high the blood calcium is. The ruddy line shows that nearly 4% of all humans go kidney stones. However, the blackness line shows that 22.five% of patients with hyperparathyroidism get kidney stones. The important thing for you to see (and teach your doctor), is that the incidence of stones does non go up as the blood calcium goes college. That is, a calcium of 12.five mg/dl does not accept a higher incidence of kidney stones than a calcium of ten.5 mg/dl.

Information technology'due south all about duration!  How long has the calcium been loftier?

This adjacent graph shows the same patients but this fourth dimension we graphed them according to how long their calcium was in a higher place 10.0 mg/dl (the upper limit of normal for adults over historic period 35) (2.51 mmol/fifty for our European and Canadian friends). So this time the bottom Ten axis is the number of years their calcium has been above 10.0 instead of how loftier the blood calcium was in the previous graph.  You tin see that the longer a person has high calcium the higher the gamble of getting kidney stones. Fifty-fifty very mild elevations of calcium for a few years dramatically increases the incidence of kidney stones.

Kidney stones vs years of high calcium

Kidney Failure

One thing that nosotros are non showing on these graphs is that the office of the kidney (how good it works to filter and make clean the blood) decreases over fourth dimension likewise. Non only do patients go kidney stones when they take high calcium for a few years, they as well begin to develop kidney failure. Nearly half of all patients who have blood calcium levels even a lilliputian bit high for 10 years will begin to get a decrease in GFR, the number nosotros apply to determine the health of the kidney. By xv years of even mild high calcium, fourscore% of patients will have some renal failure, commonly it is Stage III kidney failure at this time.  Nosotros have a blog discussing kidney failure and stones which includes x-rays and pictures.

Men vs Women; Young vs Old.

Men get kidney stones twice as often as women. This is true of all kidney stones, whether they are acquired by a parathyroid tumor or non. The incidence of stones increases with age, with the pinnacle being around threescore years of age.  Wow, guess what, the incidence of hyperparathyroidism increases with age, with the peak incidence beingness at age 60.

24 Hr Urine Test for Urine Calcium Levels

There is a test to measure the amount of calcium in your urine. This is almost always done past having you collect your pee in a jug for 24 hours and keeping that jug in your fridge the entire time (disgusting!). This test is supposed to tell your doctors if you take too much calcium in your urine, and from this they are supposed to tell you lot if you are at risk for more than stones. The concept being that people with higher calcium in their kidneys are more likely to get kidney stones. Unfortunately, it isn't that unproblematic and this exam is pretty worthless. Let's take a expect at the 24-Hour-Urine results for 10,000 of our patients who had hyperparathyroidism. This graph shows the amount of calcium forth the bottom X axis from a low almost null upwards to 1000 mg/24 hours (extremely high). The normal range is less than 350, but y'all can see that near patients with hyperparathyroidism have urine calcium that is in the normal range. We and then made every patient with kidney stones have a cherry-red dot, and those that never had a kidney stone accept a blueish dot. And guess what, they are exactly the aforementioned. The amount of calcium in the urine is the aforementioned for those with kidney stones and those without kidney stones.

If the corporeality of calcium in the urine had an influence on the formation of kidney stones in people with a parathyroid tumor, then all the blue dots (no stones) would be on the left side of the graph (low urine calcium levels) and all the red dots (do take stones) would exist on the correct side of the graph (high urine calcium).  Merely this is not the case. The ruby and the bluish dots are distributed equally along the x-axis. Thus, a 24 hour urine test cannot be used to determine which patient with high claret calcium or hyperparathyroidism is at risk of getting a kidney stone. So if your doctor wants to exercise this examination for y'all (and tells you to keep your pee in the fridge for a few days--UGH), you lot may want to take this folio to them and testify them that we can't tell who will and volition not get stones past how much calcium is in the urine.

Equally a review from above, fifty-fifty mildly elevated calcium in the Blood will dramatically increase your risk of kidney stones (and many other problems), with the risk beingness related to the duration of loftier calcium (how many years above 10.0 mg/dl), and not related at all to how HIGH the claret calcium is in the Claret or in the urine.

Signs that a parathyroid tumor is Non causing your kidney stones.

We've seen thousands upon thousands of people with kidney stones due to hyperparathyroidism. We have found a couple of things that are important for y'all and your medico to know. The typical patient with stones due to hyperparathyroidism has had one or two stones. Often information technology is one or two attacks, but the urologist says there are more inside. Usually these people accept never had a kidney stone earlier. The kidney rock problem is new. This is in distinct contrast to people who say "I've had 35 kidney stones over the past 20 years", because that is usually a kidney problem, not a parathyroid problem. Sure it is possible that you had kidney stones when you were 25 that weren't due to a parathyroid problem... and now 40 years later on you get another kidney rock assail that is due to a parathyroid tumor. We see this frequently and this is classic for a parathyroid tumor--the commencement rock was not related to parathyroid bug, and the 2nd one many years later was.

This page is written for a person who never had stones, or had a rock decades agone, and now has a new stone that is causing problems. That person has most a l% gamble that a parathyroid tumor is causing the new stone problem. If you have lots of stones for many years, so it is possible, just unlikely that a parathyroid problem is the crusade, and instead yous almost surely accept a kidney problem as the cause. Delight folks, if you accept had dozens of stones over many years, don't call u.s. (or any physician for that matter) and demand to have your parathyroid tumor removed. Lots of kidney stones over many years are well-nigh never caused by a parathyroid problem. Delight exercise not enquire for a consult with united states of america and and so tell us y'all have had stones for yr. We will put our hair out.  Hyperparathyroidism causes NEW onset of stones in people who don't otherwise accept stones. Yeah, it is possible that you are a rock former for many years, and THEN you got a new parathyroid problem. (yes it is true that you tin have diabetes and and then intermission your arm--the two are unrelated).

This folio was last updated: 08/17/2021