Kidney Stones: Tests & Diagnosis









Kidney stone is a painful medical condition that is also known as renallithiasis. A kidney stone is made of mineral and acid salts. When your urine becomes thickened, crystallization of minerals happens and gradually they stick together, causing a stone formed. In some cases, kidney stones simply pass out naturally via urine though pretty painful. While in other cases, surgical or non-invasive therapy is needed to manage the acute symptoms.  

What Are the Symptoms of Kidney Stones?

Once a stone is formed, it may block or occlude the ureter or any other parts of the urinary system, thus presenting as waves of pain and discomforts which are very hard for patients to cope with. Besides the common systems, such as nausea, vomiting and sweating, below are 2 other main symptoms of kidney stones:

  • Renal colic. Renal colic is the pain felt mainly in the deeper parenchymal tissues of the kidney. It can start all of a sudden and then weans off over time. The location is usually between the mid-ribs or sides of the abdomen, and the patients often struggle to find a comfortable position to reduce the intensity of the pain.
  • Blood in the urine. If the blockage is large, the stones may rupture the blood vessels and results in blood loss via urine. This is not, however, a conclusive indicator for kidney stones as blood can discharge in urine in other kidney related diseases as well.

Diagnosing Kidney Stones

1. What Are the Kidney Stone Tests?

If you show signs of renal stones, your doctor will conduct a series of tests in order to make a conclusive decision, such as X-rays, CT scans, urine tests and blood tests. Moreover, your family history, GI disturbances, other kidney disorders, history of medication or other health issues can significantly help your doctor with diagnosing kidney stones.

  • UrinalysisUrinalysis is a test which will use a urine sample. The sample is taken from a patient, then tested in the health care provider’s office or sent to a lab to analyze if there’s presence of stones in urine.
  • Blood Tests. A patient will be drawn blood at a health care provider’s office or commercial facility, and then the sample will be sent to a lab for analysis to check the condition and function of the kidneys, and if there are other problems causing the formation of the kidney stones.
  • Abdominal X-rays. An X-ray is used to get a pictorial view of the kidneys in order to have a complete image of the stones in your body. It can help determine the size, shape and location of the kidney stones. This helps to decide further treatment more easily. In some cases, contrast dyes are used to view an image with even more details.
  • CT scans. It is an advancement in the imaging techniques already available. During a CT scan, a computer is used to construct an image on your internal bodywith the help of radiations passing through your body. The image obtained from these techniques is clearer and more detailed than an X-ray. In addition, like an X-ray, it is a non-invasive method which makes it useful for analytical purposes.

2. How to Prepare for the Test

Kidney stones can be quiet painful, and in cases of large stones, your doctor might refer you to a specialist. Here are some helpful techniques that may help you get prepared for the kidney stone test:

  • Before the test, ask your doctor if you need to go on dietary restrictions.
  • In addition, it might help the doctor if you can provide your symptoms—related or unrelated to kidney stones may both help.
  • Also, take a friend or a family member with you for support since it must be hard for a nervous patient to remember all the things.
  • Further, keep in mind the questions that you want to inquire, such as the size of the kidney, treatment options or any alternative therapies, etc.

Understand the Your Test Results

1. General Results

If you are going to have a kidney stone analysis soon or already have had one, then it is very important for you to know the type of kidney stones in order to understand the treatment measures. But before that here are some general results after taking a kidney stone test that you should be aware of:

  • Calcium oxalate and calcium phosphate makeup majority of the stones; they can occur either together or individually.
  • A very small portion of kidney stones are made from a protein called cysteine.
  • Almost 15% of the kidney stones are composed of magnesium ammonium phosphate.
  • 10% of all kidney stones compose of uric acid.

2. Understand Your Type of Kidney Stones and the Treatment for It

Types of Kidney Stones

Diagnosing Kidney Stones

How to Treat It

Calcium Stones


Formations of calcium stones are very common. Calcium stones are usually made of phosphate, maleate and calcium oxalate. Common sources of oxalate are spinach and vitamin C. Kidney stones formed from calcium normally affects young men from 20-30 years old.

  • To treat calcium stones, low oxalate diet is required. Try to avoid foods that have oxalate content. Foods and beverages like beer, hot cocoa, nuts, tea, sesame butter, spinach and chocolate milk have high content of oxalate.
  • Even if you have kidney stones, continue to take calcium in moderate doses can aid in controlling the formation of oxalate. Taking vitamin B6 can also reduce urine output of oxalate.
  • Your doctor may also recommend that you follow low sodium diet which can aid in preventing calcium kidney stones.


Uric Acid Stones

Uric acid stones occurs due to uric acid, which is a by-product of protein metabolism. People who follow high purine diet, suffer with gout or undergo chemotherapy often get diagnosis of uric acids. Uric acids commonly affects men rather than women.

  • Treatment of uric acid stones includes low purine diet. This may require you to avoid foods high in purine like red meats, legumes and organ meats.
  • Gout is also associated with insulin resistance. To treat this, refined carbohydrates are restricted.
  • Acidic urine can cause uric acid stone formation. To lower the risk, potassium-magnesium citrate is part of the treatment to make the urine basic.

Struvite Stones

Struvite stones may result from infections. Urease is an enzyme that is produced by certain bacteria in the urinary tract. The enzyme aids in creating the ammonium that is needed for the type of stone production. The stones then grow rapidly, thus forming "staghorn-calculi".

Unlike other stones, struvite stones thrive in basic conditions and part of the treatment is urine acidification as stated in calcium phosphate stones.

Your health care provider may also treat your kidney stone by prescribing antibiotics against the infection.  

Cystine Stones


Cystine stones are not common and normally occurs due to genetic predisposition. Diagnosis of Cystinuria is done with combination of family history, presence of cystine crystals and measurement of the urinary cystine excretion.


  • Even if you have genetic disposition in developing cystine stones, you can still do something about it. The best way to prevent the formation of cystine stones is to increase fluid intake.
  • Likewise, it is important to decrease your salt intake. Doctors may ask you to lessen salt intake to reduce the cystine excretion. Intake of 50meq of sodium daily is recommended.


Watch this video and learn more about how the kidneys function and different treatment for kidney stones: