Urolithiasis

Kidney stones can develop in 1 or both kidneys and most often affect people aged 30 to 60.

They’re quite common,with more than 10% of people affected.

Kidney stones are usually found in the kidneys or in the ureter, the tube that connects the kidneys to your bladder.

The  majority of patients will not have any other stones later in their life, there are though a few risk factors that raise the chance of recurrent stone formation such as:

• eat a high-protein, low-fibre diet
• low fluid intake
• are inactive or bed-bound
• have a family history of kidney stones
• have had several kidney or urinary infections
• have had a kidney stone before, particularly if it was before they were 25 years old
• anatomic abnormalities of the kidneys like horseshoe kidney ,ureteropelvic junction obstruction and ureteral strictures
• certain metabolic abnormalities
• previous urinary diversion
• previous bowel resection, bariatric surgery or Crohn’s disease
• take certain medications like aspirin,diuretics,antiepileptics etc.

The single best way to prevent kidney stones is to make sure you drink plenty of fluids each day to avoid becoming dehydrated.

You should aim to drink up to 3 litres of fluid throughout the day, every day.

You’re advised to:

• drink water, but drinks like tea and coffee also count
• add fresh lemon juice to your water
• avoid fizzy drinks
• do not eat too much salt

If you already had a stone, then your Urologist will discuss more specific ways to prevent stone formation based on the stone composition.

The most precise and reliable method to diagnose those stones is CT scan.This is usually done in cases of severe pain and for investigations for urinary symptoms, blood in the urine,chronic back ache or they are found incidentally when a scan is done for other reasons. When CT scan is not available, an ultrasound scan can be done initially.

Very small kidney stones are unlikely to cause many symptoms. They may even go undetected and pass out painlessly when you pee.

Larger kidney stones can cause symptoms, including:

• pain in the back or groin – men may have pain in their testicles
• a high temperature
• feeling sweaty
• severe pain that comes and goes
• feeling sick or vomiting
• blood in your urine
• urine infection

A kidney stone that blocks the ureter, the tube that connects your kidney to your bladder, can cause a kidney infection.This is because waste products are unable to pass the blockage, which may cause a build-up of bacteria.

The symptoms of a kidney infection are similar to symptoms of kidney stones, but may also include:

• a high temperature
• chills and shivering
• feeling very weak or tired
• cloudy and bad-smelling urine

In this case the blocked kidney needs to be unblocked by putting an internal stent or a tube to the kidney called nephrostomy.

No, small ureteral stones are likely to pass spontaneously with or without the aid of painkillers and medications that relax the ureter. On the other hand big kidney stones are impossible to pass spontaneously and surgery to remove them is necessary.

If a patient has a stone there are multiple factors that play a role in the decision as to whether it needs treatment like its size, location, possible composition, patient’s previous history and overall health status. The main types of surgery for removing kidney stones are:

• shockwave lithotripsy (SWL)
• ureteroscopy
• percutaneous nephrolithotomy (PCNL)

Shock wave lithotripsy involves using ultrasound (high-frequency sound waves) to pinpoint where a kidney stone is.Ultrasound shock waves are then sent to the stone from a machine to break it into smaller pieces so it can be passed in your urine.

SWL can occasionally be an uncomfortable form of treatment, so it’s usually carried out after giving pain killing medication.

It is considered the least invasive form of treatment and it is suitable for smaller kidney stones that look “soft” on imaging.

More than 1 session of SWL may be necessary to successfully treat kidney stones.

Ureteroscopy involves passing a long, thin telescope called a ureteroscope through the urethra and into the bladder.It’s then advanced up into the ureter, which connects your bladder to your kidney.

The Urologist may either try to gently remove the stone using another instrument, or they may use laser energy to break it up into small pieces so it can be passed naturally in your urine.

It is a very safe and effective way of treating ureteric and kidney stones and the patient can usually go home on the same day of the operation 

Percutaneous nephrolithotomy involves using a thin telescopic instrument called a nephroscope that is put directly to the kidney through a small incision of the skin.It is considered nowadays the most invasive modality for stone treatment and it is reserved for very large stones of the kidney.With the evolution of ureteroscopy the indications for percutaneous nephrolithotomy are becoming rarer and rarer. 

When a kidney or ureteral stone is removed,the fragments are sent for analysis so that the Urologist knows the exact composition.Then if the patient is deemed to be at high risk for stone recurrence based on the stone composition or medical history,further metabolic evaluation is warranted. This will help identify,if possible,the underlying metabolic abnormality responsible for stone formation and guide further treatment and prevention strategies.