Kidney Stone

Almost 30% of the world population are suffering or have suffered from kidney stones. If youve been detected with one don’t worry ! We at Urocentre are there to help you. First we will understand regarding the symptoms, investigations and then the treatment options available for the management of these stones.

Symptoms of Stone Disease

The symptoms of the renal stone disease include one or more symptoms of these:

Pain in the flank region: This is the most common and persistant symptom associated with the renal stones. It may vary in intensity from being very severe and intolerable to mild and aching pain which may radiate from the flank region to the groin region.

Nausea and vomiting: these symptoms are also common with the stone disease as the nerve supply of the bowel and kidney overlap in our body hence these symptoms are also common after the irritation/inflammation of the urinary tract.

Fever : If the stones are associated with the bacterial infection in kidney then may lead to fever.

Blood in the urine: It may also be presenting symptom along with pain in the patients, as the stone causes the irritation/inflammation of the urinary tract in the kidney this leads to the hematuria or blood in urine.

Foul smelling urine: This may also be a symptom when the urine is infected due to chronic indwelling bacteria in the kidney stone.

Symptoms of renal failure: These may also be present if the obstructing stone is present in both the kidneys leading to the stasis of urine in the body or in cases of only one functioning kidney where the stone obstructs the outflow of urine from the kidney.For the symptoms refer to the section of renal failure.

Risk Factors for Kidney / Renal Stones

There are some risk factors for the formation of the kidney stones that we need to understand and work on. These include

Dehydration/less water intake. 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 due to less amout of urine production which is not enough for flusing the forming stones.
Family or personal history. If someone in your family has kidney stones, you’re more likely to develop stones,as the excretion of certain stone forming compounds have a genetic link. And if you’ve already had one or more kidney stones, you’re at increased risk of developing another.
Foods that we eat. Eating a diet that’s high in oxalates,protein, sodium (salt) and sugar may increase your risk of some types of kidney stones. Too much salt in your diet increases the amount of calcium your kidneys must filter and significantly increases your risk of kidney stones.
Obesity. High body mass index (BMI) and obesity have been linked to an increased risk of kidney stones due to the increased load to various stone forming compounds in the urine.
Various surgeries. Gastric bypass surgery, inflammatory bowel disease or chronic diarrhea 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.
Other medical conditions. Diseases and conditions that may increase your risk of kidney stones include renal tubular acidosis, cystinuria, hyperparathyroidism, certain medications and some urinary tract infections.

How can we detect and diagnose Renal Stones

Kidney stones are most commonly diagnosed on an ultrasound. But there are some other tests too that can help to diagnose the stones and help the doctor to manage the stones.

Ultrasonography: in this test the sound waves travel through the body and various body organs are seen according to the amount of the sound waves reflected by them. This test is very good to assess the kidneys it tells the presence of the stones ,its approximate size, location in the kidney and stasis of urine in the kidney (hydronephrosis).

X ray KUB(kidney,ureter,bladder): this is the xray of the abdomen which extends from the below the chest area to the pelvic area.usually the stones appear as the radiopacity at the kidney shadow area but radiolucent stones are not visible over the xrays

Plain CT KUB: This is a very sensitive test to diagnose the presence of the stone, their location, size presence of hydronephrosis, density of the stone very accurately.it is investigation of choice for the acute colic pain.

Contrast studies(CT IVU/ IVU): In these investigations we use contrast which is injected in the veins and then excreted in the urine. This along with the details of the stone also tells about the functional status of the kidney and better for the visualization of the urinary tract.

How do we treat Kidney Stones

Now let us discuss the treatment of the renal stones in a simple manner. Principally the treatment of the renal stones is based on the number, total size and the location of the kidney stones.

For the kidney stone of size less than 8mm the treatment is mainly nonoperative/conservative. This includes some dietary modifications and fluid changes. Here are some suggestions:

Fluid changes: The amount of fluid needed to help prevent kidney stones varies for each person For example, some people sweat more than others and need to drink more, hence what we want for our patients to produce more than two litres of urine per day. A helpful indicator that you’re drinking enough water is the colour of your urine. If it’s dark yellow, you’re probably not drinking enough.
Decrease/reduce salt intake: A diet high in sodium can cause kidney stones by increasing the amount of calcium in urine.Sodium can also cause high levels of the amino acid cystine in urine, leading to cystine stones.
Decrease sugar intake . Food and drinks with high natural and added sugars can increase your risk of developing kidney stones. When we consume sugar, urine calcium level rises and your urine volume goes down, contributing to kidney stones.
Do not avoid calcium-rich foods: While high levels of calcium in the urine put you at risk for developing kidney stones, this doesn’t mean you should avoid calcium-rich foods. Calcium can actually deter substances in the digestive tract that contribute to kidney stones.
Reduce protein intake: Limit your consumption of animal proteins, such as beef, chicken, pork, fish, and eggs. Too much animal protein can also increase the amount of calcium in the urine and reduce the amount of citrate, a form of citric acid that acts as a stone inhibitor
Adopt balance diet: A diet rich in fruits and vegetables, whole grains, and legumes is important for people with any form of kidney stones. Eating a healthy diet ensures that you get enough potassium, magnesium, and citrate, which are all nutrients that may help prevent kidney stones.
Consider limiting oxalate-rich foods. If you’ve had calcium-oxalate stones, you may want to limit your consumption of foods high in oxalate.Examples of foods high in oxalate include beans, berries, nuts, soy, sweet potato, wheat bran, and dark green vegetables such as spinach.

A number of drugs are available which help in dissolution of the stones:

Potassium citrate:which lowers the acidity of urine. Lowering urine acidity can help prevent uric acid and cystine stones. This medication also raises the citrate level in the urine, preventing calcium stones.
Thiazide diuretics lower calcium levels in the urine, helping to prevent calcium stones. They also increase the amount of urine produced, which helps prevent stones from forming.
Allopurinol prevents the breakdown of substances called purines into uric acid, lowering the amount of uric acid in the urine. It’s mostly used to prevent uric acid stones.
Cystine-binding thiol drugs are given to people with cystine stones. These drugs bind to cystine in the urine, preventing cystine crystals from forming and developing into stones.

Indications for the Surgical treatment can be

Failure of the medications to get the stone removed
Bothering pain on/off not settling down
Stone leading to urinary tract infection

Options for treatment can be:

ESWL(Extracorporeal shock wave lithotripsy) : it is treatment where the high energy shock waves(of sound) are focused over the kidney stone and then blasted. This is a very effective treatment for the smaller sized, radiopaque, less dense stones. It’s a daycare treatment, where no incision/cut is made over the body and no anaesthesia is required(except in the children). Usually this form of treatment may require 2 or 3 sessions depending on the stone composition.
RiRS(Retrograde intrarenal surgery): this is also a very effective treatment modality for the clearance of the small stones.here a small very flexible scope is passed upto the kidney from the urethra,bladder, ureter and then to kidney and using laser energy the stone is fragmented to dust. This technique has got higher clearance rates and very effective for the small stones.
MINIPCNL: in this procedure the kidney is directly excessed through the small hole made from the surface of the skin and then scope and lithoclast are passed through the dilated hole. The stone is fragmented using the lithoclast or the laser and then is removed. This procedure has the highest stone clearance rates among all above mentioned procedures

For the stone of size( 8 to 20mm)

Here the conservative management usually fails and hence operative management is the considered the first option. Available options are:

ESWL: this is only effective when the stone density is less which is measured in HU. The HU should be less than 1000 so that this technique be effective and the skin to stone distance should be less than 10cm so that the shock waves can target and reach the stone.

RIRS(Retrograde intrarenal surgery)

MINIPCNL/PCNL: in this procedure the kidney is directly excessed through the small hole made from the surface of the skin and then scope and lithoclast are passed through the dilated hole. This procedure has the highest stone clearence rates among all above mentioned procedures

For the stone of size( more than 20mm)

Because of the large size of the stone the operative management is the considered the first option.

PCNL: in this procedure the kidney is directly excessed through the small hole made from the surface of the skin and then scope and lithoclast are passed through the dilated hole. The stone is fragmented using the lithoclast or the laser and then is removed. This procedure sometimes may require 2 sessions for complete clearance of the stones if there are a large number of stones or very large sized stones.