Kidney stones: an expert's overview: part 1
Written by:Kidney stones are an extremely common medical problem, which can cause immense pain. In the first article of a two-part series, we speak to renowned consultant urological surgeon Mr Jyoti Basu, who gives us an insight into the formation of kidney stones, common symptoms and when to seek medical attention.
What are kidney stones, and what causes them to develop in the urinary system?
Kidney stones are stones which are commonly made up of calcium and oxalate; these types occur most frequently. There are also other types of stones such as uric acid stones, which are made up of a combination of calcium, magnesium, and aluminium phosphate.
Furthermore, some rare types of stones can occur due to metabolic abnormalities like cysteine, which occur when there is an inborn error of metabolism. This error takes place when people have a developmental abnormality whereby they cannot handle the cystine (an amino acid) in their body.
As a result, the cysteine, which is normally reabsorbed back, cannot be reabsorbed. The groups of cysteine then filter through the kidneys and form clumps of stones. These types of stones are not very common but can affect around 1- 2% of people.
The most common types of stones are:
- Calcium oxalate stones
- Uric acid stones
- Stru white or infective stones
- Calcium phosphate stones
There are several theories as to why they form but one of the most common reasons that they occur is due to the lack of fluid. People are habitually concentrating their urine too much because of their lack of fluid intake, as well as their natural tendency to form stones.
If people have a natural tendency to form stones because of their genetic makeup, they will form stones and obviously compounded by this, are circumstances such as:
- Living in a very hot climate.
- Experiencing a lot of stress.
- Working in a very hot environment.
- Not drinking enough.
- Having a propensity to form stones.
What are the common symptoms and signs of kidney stones, and when should I seek medical attention?
Symptoms of kidney stones are varied. Patients can vary from being completely asymptomatic to being in extreme agony. Surprisingly, sometimes people don't even know that they have any stones. If the stone is in the kidney, the majority of the time, it won’t cause a problem unless there is an associated complication, such as an infection.
If this is the case, patients then start to realise there is a stone because they get pain, discomfort and bleeding. The pain can be in the kidney region or in the loin. When the stone then moves down into the ureter or the pipe joins the kidney down to the bladder, then they get to start to get the severe, agonising pain.
Some people have described this pain to be worse than labour. The most severe complication is when the stone comes down and blocks the kidney because it is lodged in the ureter. It can move and then the urine on top gets piled up and that gets infected.
This potentially life-threatening condition is referred to as an infected obstructed kidney. It is a medical emergency which has a mortality rate and requires urgent medical attention. Frequently patients are going into ITU or HTU because they're septic and the only way to deal with this is to drain the kidney by putting in a drain colon nephrostomy.
As previously mentioned, in some cases stones can be completely asymptomatic, and they present with a massive stone, called a staghorn calculus. Patients can have a staghorn calculus and be completely oblivious to it; they only find out because they've had a CT scan for something else, and the stones appear on the scan.
How are kidney stones diagnosed, and what imaging techniques are used to detect and evaluate them?
Kidney stones are diagnosed based on the symptoms, therefore if somebody has got pain, blood in the urine or discomfort, it will be necessary to visit a doctor.
In most cases, the patient will complain of pain in the region of the kidneys, in the back or just under the ribcage. Doctors will consider kidney stones as a possible cause, after thorough examination.
By and large the first modality of investigation, other than doing a urine test (which may show signs of blood or infection), is to do an ultrasound scan. The ultrasound scan can give doctors an indication as to what's happening.
Although an ultrasound scan is not the investigation of choice, in primary care or with GPs, an ultrasound scan will probably be done in order to determine what is happening. However, the diagnostic test of choice for a stone is a CT scan. Once the ultrasound scan has been performed and the GP of the primary care has revealed a stone, it is important to confirm the position, location, and exact size by a CT scan, because an ultrasound scan cannot always accurately record the size of the stones. A CT scan is crucial to determine what type of stone it is.
If you are suffering from kidney stones and would like to book a consultation with Mr Basu, simply visit his Top Doctors profile today.
