What is a Kidney Stone ?

The kidney acts as a filter for blood, removing waste products from the body and making urine. It also helps regulate electrolyte levels that are important for body function.

In some people, Chemicals/Minerals crystallize in the urine and form the beginning, or nidus, of a kidney stone. Theses stones are very tiny when they form, smaller than a grain of sand, but gradually can grow over time to several Centimeters big.

Types of Kidney Stone

Calcium stones:

Most kidney stones are calcium stones, usually in the form of Calcium Oxalate. Calcium stones may also occur in the form of Calcium Phosphate.

Struvite Stones:

Struvite stones form in response to an infection, such as a urinary tract infection. These stones can grow quickly and become quite large, sometimes with few symptoms or little warning

Uric acid stones:

Uric acid stones can form in people who do not drink enough fluids or who lose too much fluid, those who eat a high-protein diet, and those who have gout. Certain genetic factors also may increase your risk of uric acid stones.

Cystine stones:

These stones form in people with a hereditary disorder that causes the kidneys to excrete too much of certain amino acids (Cystinuria).

Kidney Stones Imaging

  1. CT KUB Scan: It is the investigation of choice for detection of Kidney Stones. Almost all stones are detectable on CT scans. It is not advisable for children.
  2. X-Ray KUB: It is done when ultrasound and CT scan facility is not available. Radio-opaque stones may be visualised in the Kidneys, Ureters or Bladder. It is generally not recommended due to exposure to radiation and poor diagnostic value.
  3. Ultrasound KUB: Ultrasounds can sometimes be useful, because it gives details about the presence of hydronephrosis, suggesting that the stone is blocking the outflow of urine. Radiolucent stones, which do not appear on X-Rays, may show up on ultrasound imaging studies.

Other advantages of renal ultrasonography include its low cost and absence of radiation exposure. Ultrasound imaging is useful for detecting stones in situations where X-rays or CT scans are discouraged, such as in children or pregnant women.

Signs and symptoms

A kidney stone may not cause symptoms until it moves around within your kidney or passes into your ureter – the tube connecting the kidney and bladder

Severe pain in the side and back, below the ribs extending upto groin.

Nausea and vomiting

Fever and chills if an infection is present

Pain while urinating pink, red or brown urine cloudy or foul-smelling urine

Persistent need to urinate

Risk Factors:

Factors that increase your risk of developing kidney stones include:

Family or personal history:

If someone in your family has kidney stones, you are more likely to develop stones, too. And if you have already had one or more kidney stones, you are at increased risk of developing another.

Other medical conditions:

Diseases and conditions that may increase your risk of kidney stones include renal tubular acidosis, Cystinuria, Hyperparathyroidism, certain medications and urinary tract infections.


High body mass index (BMI), large waist size and weight gain have been linked to an increased risk of kidney stones.


Not drinking enough water each day can increase your risk of kidney stones. People who live in warm climates and those who sweat a lot may be at higher risk than others.

Digestive diseases and surgery:

Gastric bypass surgery, inflammatory bowel disease or chronic diarrhoea can cause changes in the digestive process that affect your absorption of calcium and water, increasing the levels of stone-forming substances in your urine.



USG is investigation of choice for suspected stone X-ray, Ultrasound, CTKUB

Urine Test

The 24-hour urine collection test may show that you’re excreting too many stone-forming minerals or too few stone-preventing substances.

Blood Test

Blood tests may reveal too much calcium or uric acid in your Blood. It can help monitor the health of your kidneys and other medical conditions.

Analysis of Passed Stones

You may be asked to urinate through a strainer to catch stones that you pass. Lab analysis will reveal the makeup of your kidney stones. Your doctor uses this information to determine what’s causing your kidney stones and to form a plan to prevent more kidney stones.


ESWL : Extracorporeal Shock Wave Lithotripsy

Extracorporeal shock wave lithotripsy (ESWL) is the procedure to break the kidney stones in smaller parts for their easy passage through the urinary tract.

The patient may feel discomfort and there would be dull ache for 1-2 days after treatment.

patient may require multiple sessions.

PCNL : Percutaneous Nephrolithotomy

It is a minimally invasive procedure to remove kidney stones by a small puncture(upto 1 cm) through the skin.

Due to advent of newer and less invasive surgical options, PCNL is now generally used to remove  stones > 2cms in size.

It is usually done under General or Spinal Anaesthesia and the patient can be discharged the next day.

Laser URS

Laser URS can be recommended by your surgeon if you have large stone in the ureter bladder. It is a minimally invasive procedure where your doctor inserts telescope like instrument called Ureteroscope through the opening of your urinary tract and examine, ureters & bladder then locates the kidney stone and breaks apart using laser energy which means there are no cuts and incision made.

RIRS (Retrograde Internal Surgery)

It is a minimally invasive procedure for removal of Renal and Upper Ureteric Stones. A flexible fiberoptic endoscope is placed into the urethra, into the bladder and then through the ureter into the kidney. The stone is seen through the scope and and then can be removed intact in case of small stones or vaporised by a laser in case of larger stones.

It is generally done under General Anaesthesia. There is minimal bleeding and pain and the patients can be discharged the same day.

Mini PERC (Miniaturised Percutaneous Nephrolithotomy)

It is the latest surgical modality for treatment of surgical stones which cannot be operated by RIRS. Due to advancement of technology, the kidney stone can be operated through a very small “keyhole” incision which reduces bleeding and improves recovery period as compared to standard PCNL.

It is usually done under General or Spinal Anaesthesia and the patient can be discharged the next day.