What is it?
A kidney stone is a particle that forms in our kidneys, and if it’s big enough, it can get stuck.This is extremely painful. The pain typically comes in waves, beginning from the lower back and radiating to the groin. Other symptoms can include nausea, vomiting, and fever.
The risk of someone in the developed world having kidney stones during their lifetime is 10-15%. 65-80% of those with kidney stones are men. The average age of onset is somewhere in the 40s, and a fair number of those who had have kidney stones once will have them again.
What causes it?
Many substances can be the building blocks of kidney stones – these include calcium, ammonia, uric acid, and cysteine. Basically anything that increases the amount of these minerals in the urine is also a risk factor of developing kidney stones. Examples of this include high dietary intake of certain things, metabolic dysfunctions, and some medications. Dehydration is also a major factor in stone formation.
What happens during it?
If you cook pasta and add salt to the cooking water, you’ll notice that only a certain amount of salt dissolves into the water, while the rest remains as small but visible particles. Dissolving happens when water molecules form bonds with the salt ions. Because one ion attracts many water molecules and there are only so many water molecules available, some of the salt has to remain in solid form. This point where the liquid can’t dissolve anymore of the solid substance is called a saturation point. If this happens in our urine, either due to too little liquid or too many minerals, kidney stones can form.
Our urine contains minerals. If they form particles, they most often remain very small and are removed from our bodies with urine. Sometimes these minerals can aggregate into too big particles, and these particles can get stuck inside the kidney or the tubes that lead from the kidneys to the bladder.
How can it be treated?
Most kidney stones pass spontaneously. This can take weeks, though, and pain medication is often a very good idea.
Large kidney stones with little chance of going away spontaneously can be managed through a number of ways. The most popular one is trying to break the stones down with ultrasound. Sometimes, a long thin tube can be passed along the urine pathway, and when it comes to the kidney stone, the doctor can either try to remove it or to break it down with laser.
Sources: https://en.wikipedia.org/wiki/Kidney_stone, http://www.nhs.uk/Conditions/Kidney-stones/Pages/Treatment.aspx