What does a kidney stone look like?

Kidney stone are tiny crystals that can form into small, pebble-like stones in the kidneys. Some may also block the urinary tract. Therefore depending on the composition of the kidney stones, their appearance may vary.

This article will explain kidney stones, their causes, symptoms, treatment options, and prevention.

What do they mean?

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Trusted Source kidney stones can form when there is a high level of certain substances in the urine, such as Calcium.

The size of kidney stones can vary, and they can be either smooth or jagged. They are often brown or yellow.

Which types of kidney stones are there?

There are four main types of kidney stones.

Source :- https://www.caresathome.com/blog/kidney-stone

Calcium stone

One 2016 article, Trusted Source, says that calcium stones are the most prevalent type of kidney stone.

Calcium stones can contain calcium oxalate or calcium phosphate.

Calcium oxalate stone comprises calcium oxide dihydrate (COD) and calcium oxalate monohydrate (COM).

A kidney stone made from calcium oxalate and COD crystals will have jagged edges. A kidney stone made from calcium oxalate and COD crystals, the more common type, will have a smoother surface.

 Brushite is another crystal that forms tiny rosettes from very thin, sharp crystals.

Brushite is another crystal that forms tiny rosettes out of very fine, sharp crystals.

Uric acid stone

A 2018 article stated that uric acid stone accounts for 3-10%Trusted source kidney stones.

Uric acid stones look almost pebble-like. These stones can appear hard from the outside but soft on the inside because they contain different uric acids and calcium oxalate monohydrates.

Struvite stone

Struvite is the next most common type, with 7-8%Trusted Source of people having them.

These stones are more powerful than other stones.

Cysteine stone

Cysteine stones can be caused by cystinuria. This condition can be passed down from one generation to the next.

Cysteine, a type of amino acid produced by the kidneys, leaks into the urine in cystinuria patients.

Cysteine stones can be compacted, opaque to a small extent, amber.


The following symptoms are indicative of kidney stones:

  • Sharp pains in the back and side, lower stomach, groin, and side
  • The urine may contain pink, red, or brown blood
  • A constant need to urinate and pain when urinating
  • Being unable to urinate or able to urinate only a little
  • Urine that smells or is cloudy
  • nausea
  • vomiting
  • fever
  • Chills


The kidney can filter out most waste chemicals from urine, including Calcium and phosphate. , however, the kidney may not filter out these harmful substances.

According to the National Kidney Foundation, this can occur when there are too many waste products and not enough liquid in a kidney. This causes crystals to form.

These crystals can form into kidney stones.

Sometimes, however, these stones can be difficult to pass. This causes the body to retain urine, causing pain.

Removing kidney stone

Some people may pass kidney stones without the need for medical treatment.

The Urology Care Foundation states that smaller stones are more likely than larger stones to pass because they are less likely to block the urinary tract.

A stone can take up to six weeks to pass. Drink plenty of water.

When a kidney stone is removed, people are more likely to feel pain. People should seek medical attention if the pain becomes unbearable.

So doctors may recommend stronger pain relief medications, anti-nausea medication, or a medicine called Tamsulosin. Tamsulosin relaxes a portion of the urinary tract called the ureter. This makes it easier to pass a kidney stone.

A doctor might ask someone to use a device for catching kidney stones. This will allow them to identify the type and suggest treatment.

Passing stone depending on size.

One article states that the average size for a ureter (in) is 3-4 mm (in).

The size of a person’s kidneys will determine their chances of passing them.

  Stone size (in mm)                               How many people pass (%)
Below 480
More than 620

   Medical treatment  

A doctor might recommend surgery to remove large kidney stones and stones that block the bladder.

 A urologist is a specialist in kidney surgery and can remove or break down kidney stones.

There are three types of surgery Trusted Source.

  • Shockwave lithotripsy: This breaks down kidney stones into smaller pieces that can pass through the urinary system.
  • Ureteroscopy and Cystoscopy: These procedures use a camera that finds stones in the bladder or urethra. After a urologist has found the kidney stones, they can either remove them completely or break them down into smaller pieces passed through the urine.
  • Percutaneous kidney lithotomy: A urologist will place a camera into the kidney through its back to remove any stones. The urologist might use a laser to remove large stones.


A person can help do the following to help prevent kidney stones:

Keep hydrated

Unless they have severe kidney disease, the NIDDK recommends consuming 6-8Trusted Source 8-ounce glasses of water per day.

It is best to drink water to dilute urine, but citrus drinks like orange juice or lemonade can protect Trusted Source against kidney stone formation. They contain citrate, which prevents crystals from becoming kidney stones.

Take your medication

The table below Trusted Source outlines which medications a doctor might prescribe for each type of kidney stone.

Type of kidney stoneMedication
Calcium stonesPotassium citrate

Uric acid stones

Potassium citrate
Struvite stonesAntibiotics

Acetohydroxamic acid
Cystine stones
Mercaptopropionyl glycine

Potassium citrate


The following nutrition tips can help keep them away from returning if they know what type of kidney stones have, they had in the past.

Type of kidney stoneNutrition advice
Calcium oxalate stonesreduce the intake of oxalates, such as nuts and nut products, legumes, rhubarb, spinach, and wheat bran

reduce the intake of sodium

limit animal protein, such as dairy products, eggs, fish, and meat
Calcium phosphate stonesreduce the intake of sodium

limit animal protein, such as dairy products, eggs, fish, and meat

limit legumes, soy foods, nuts, and sunflower seeds
Uric acid stoneslimit animal protein, such as dairy products, eggs, fish, and meat

limit legumes, soy foods, nuts, and sunflower seeds

eat a healthful diet and increase physical activity if a person has obesity
Uric acid stones
stay hydrated

Avoid caffeinated and sugary drinks.

A 2019 study Trusted source found that caffeine, particularly coffee, can increase the likelihood of developing recurring kidney stones.

Drinks with a lot of sugar can also increase the likelihood of Trusted Source developing kidney stones.

Risk factors

Several factors could increase the likelihood of someone forming kidney stones.

  • Not drinking enough water 
  • Too much or too little exercise
  • Obesity
  • weight loss surgery
  • Too much salt and sugar in food
  • Fructose-containing foods and drinks should be avoided

Pre-existing conditions

If they have had kidney stones, people are more likely to trust a Source.

  • A blockage of the urinary tract
  • obesity
  • cystinuria
  • gout
  • Recurrent Urinary Tract Infections
  • Cystic kidney disease
  • digestive problems
  • Hypercalciuria is an inheritable condition in which the urine has too much Calcium.
  • Hyperoxaluria is a condition in which the urine contains too many oxalates.
  • Hyperparathyroidism is a condition in which the body releases too many parathyroid hormones therefore with more Calcium in the blood.
  • Hyperuricosuria is a condition in which the urine has too many uric acids.
  • Renal tubular acidosis is when the kidney doesn’t remove acids from the urine and keeps the acid in the blood.


The following medications make it more likely for people to develop kidney stones.

  • Diuretics are used to help the body eliminate excess water.
  • Calcium-based antiseptics
  • Indinavir is a drug that combats HIV
  • topiramate, an anti-seizure medication


According to the NIDDK Trusted, doctors diagnose kidney stones through a medical history and physical examinations.

A doctor might request a sample of your urine.

In addition a doctor can determine the type of kidney stones in a person’s urine and blood by performing tests.

Doctors might also order an abdominal radiograph or a CT scanner.

These tests enable a doctor to see how many kidney stones someone has and how big they are.

How to visit a doctor

If you have symptoms of kidney stone disease, you must see a doctor.

According to the trusted Source, kidney stones can be prevented by seeking treatment.

  • Urine containing blood
  • Severe pain
  • Urinary tract infections and kidney infections
  • Loss of kidney function


There are four types of kidney stones. Each one is made up of different chemicals. So each type of kidney stone is different and may need a different medication to prevent them from coming back.

Although people can sometimes pass kidney stones by themselves, they might need to be assisted by a doctor. A person may need surgery if a kidney stone becomes stuck or very large.