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Your Questions Answered: Kidney Stones

Your Questions Answered

In this month’s Your Questions Answered series we take a look at some of the common urological conditions that people experience.

Mr Leye Ajayi is a Consultant Urological Surgeon at St John and St Elizabeth Hospital, specialising in minimally invasive surgery for urinary tract stone disease, prostate cancer and other conditions of the urinary tract. Here, he speaks to us about some of the most common questions that are asked by patients with kidney stones.

What are kidney stones?

Kidney stones are a calcified substance that forms in the urinary tract. There are trace elements within the urinary tract which most patients usually pass this without any problems, but sometimes these form into a larger stone, and that’s when it causes a problem and blocks the kidney.

What causes kidney stones? 

The cause of kidney stones in most of our patients is dehydration – they just haven’t been drinking enough water. The problem is exacerbated when they exercise a lot, and sweat as a result.

There are also certain metabolic genetic disorders: certain patients who have infections and certain patients who have a high uric acid level in their urine which causes them to form kidney stones. There are also some other genetic disorders such as renal tubular acidosis which affects the way urine acidifies and can result in kidney stones.

What does having a kidney stone feel like?

Many people have described it as the most excruciating pain that exists. It’s a sudden onset of pain in the side of the loin, which is overwhelming and essentially poleaxes the patient. It can also be associated with nausea and vomiting. If the kidney is obstructed it can cause the patient to have a fever. Often it’s an emergency, which results in a visit to the local accident and emergency, where the patient requires prompt analgesia in an effort to relieve the pain.

What is the treatment?

While the majority of patients pass the stone spontaneously, there are a number of treatments available should this not occur.

In some cases we have to go in internally, through the natural corridors of the body – through the urethra, up into the bladder and the ureter, and then we can laser the stone using a holmium laser.

When a patient has a very large kidney stone, it’s not possible to use a laser, so we sometimes have to come from the back using true keyhole surgery, with a procedure called a percutaneous nephrolithotomy, where we essentially make a little puncture to the kidney. We don’t actually cut the kidney – we dilate it, which gives straight access into the kidney so we can then break the stones and remove them.

There is also a non-surgical technique called lithotripsy, where we lie the patient on a machine and focus electromagnetic energy under the patient which breaks the stone into sand particles in the hope that the patient can then pass them spontaneously.

Interested in a consultation with our experienced team?

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