Nepedia
Back to Discover
Advanced Reader
🧬

Kidney stone disease

life science Maturity 11-13 Next article →

Kidney stone disease, also called urinary stone disease, is a condition known as a crystallopathy. It occurs when there is an excess of minerals in the urine and not enough liquid for hydration. This imbalance causes tiny crystals to clump together and form hard masses called calculi. These stones can form anywhere in the upper urinary tract. Because they often form in the kidney, they are frequently called renal calculi.

Blausen 0595 KidneyStones
Blausen 0595 KidneyStones

This condition affects between 1% and 15% of people globally at some point in their lives. It is a widespread medical issue that continues to rise in prevalence worldwide.

The formation of these stones happens through a specific three-phase process. First, the urine becomes supersaturated. This means the urine contains more solutes than it can normally hold in a solution. During this phase, nucleation occurs, which is the creation of initial seed crystals. Next, the stones undergo a growth phase where single crystals expand in size. Finally, aggregation occurs when multiple crystals clump together into an organized mass.

Staghorn Kidney Stone Progression
Staghorn Kidney Stone Progression

This process often happens more quickly through heterogeneous nucleation, where crystals grow on a solid surface like the renal papilla.

Medical professionals classify kidney stones in two primary ways. They are first classified by their specific location in the urinary tract. Nephrolithiasis refers to stones located in the kidney. Ureterolithiasis describes stones found in the ureter. Cystolithiasis refers to stones located in the bladder.

Stones are also classified by their chemical composition. The most common type is calcium oxalate, which makes up 70% to 80% of human stones. Other types include calcium phosphate, uric acid, struvite, or cystine.

Calcium oxalate crystal
Calcium oxalate crystal

Many factors influence whether a person develops these stones. Genetics play a role, as twin studies suggest a heritability of about 50%. Environmental factors and lifestyle also matter significantly. Dehydration from low fluid intake is a major risk factor. High dietary intake of animal protein can increase the risk by creating an acid load in the urine. This increases the excretion of calcium and uric acid while reducing citrate.

Staghorn Kidney Stone 08779
Staghorn Kidney Stone 08779

Additionally, diets low in magnesium or high in sodium can contribute to stone formation.

Symptoms can vary depending on the size and movement of the calculus. A very small stone may pass through the urine stream without any symptoms. However, if a stone grows large enough to block the ureter, it causes renal colic. This is extremely sharp, intermittent pain that radiates from the flank to the groin.

Pos-renal
Pos-renal

This pain often comes in waves lasting 20 to 60 minutes due to the contractions of the ureter. Other symptoms include blood in the urine, nausea, vomiting, and frequent urination.

Humans have been dealing with this condition for thousands of years. Descriptions of surgery to remove kidney stones date back as far as 600 BC. In ancient India, a person named Sushruta performed these early procedures. In modern times, the scale of the disease is significant. In 2015, there were approximately 22.1 million cases reported globally. This resulted in about 16,100 deaths. The disease has become more common in the Western world since the 1970s.

Treatment and prevention focus on managing symptoms and reducing future risks. For small stones, doctors may use medications like tamsulosin to help them pass. Larger stones might require medical procedures like extracorporeal shockwave therapy (ESWT) or laser lithotripsy (LL).

Lithotriptor machine
Lithotriptor machine

To prevent stones, doctors recommend drinking enough fluids to produce more than two liters of urine per day. Avoiding soft drinks containing phosphoric acid, such as colas, is also advised. Maintaining proper mineral levels through diet can help keep the urinary system healthy.

593 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (18)
File:Pos-renal.png
Pos-renal.png
File:Kidney stone composed of calcium oxalate showing sharp edges.jpg
Kidney stone composed of calcium oxalate...
File:Staghorn Kidney Stone Progression.png
Staghorn Kidney Stone Progression.png
File:Struvite crystals dog with scale 1.JPG
Struvite crystals dog with scale 1.JPG
File:Calcium oxalate crystal.jpg
Calcium oxalate crystal.jpg
File:Calcium phosphate crystal.jpg
Calcium phosphate crystal.jpg
File:Uric acid crystal.jpg
Uric acid crystal.jpg
File:Struvite crystals.jpg
Struvite crystals.jpg
File:Cystine crystals.jpg
Cystine crystals.jpg
File:Surface of a kidney stone.jpg
Surface of a kidney stone.jpg
File:Kidney stones, Uric acid.JPG
Kidney stones, Uric acid.JPG
File:Lenticular kidney stone.jpg
Lenticular kidney stone.jpg

+ 6 more

More to explore

✨ What else?

Related topics you might enjoy

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.