What are kidney stones?
Kidney stones, or renal calculi, are hard masses of salts and minerals formed within the urinary tract. These could be as small as a sand particle or as big as a ping pong ball and can occur in any part of the urinary tract. They are initially small and gradually increase in size over time.
Urine passes from the kidney to the bladder via a tube known as the ureter. The stones may cause excruciating pain, bleeding, and blockage of the ureter depending on the size of the stone.
What are the different types of kidney stones?
- Calcium stones
- Uric acid stones
- Struvite stones: Chronic urinary infections lead to the formation of ‘struvite stones’ which are composed of magnesium ammonium phosphate
- Cystine stones (these are rare)
What causes kidney stones?
- A positive family history
- Medical conditions like cystinuria, hyperparathyroidism, repeated urinary tract infections
- Gastric bypass surgery
- High consumption of sugar, salt, and animal proteins
- Certain medicines such as anti-epileptic medicines, calcium supplements etc.
What are the symptoms of kidney stones?
Kidney stones don’t cause pain unless they move within the kidney or pass into the ureters. The pain typically occurs on one side of the back or the abdomen, and it may radiate to the groin region. The pain is sharp, intense, and cramping kind and it may come and go. Other symptoms include –
- Frequent urge to urinate
- A small quantity of urine
- Blood in the urine
- Discolouration of urine (orange, brown or pink colour)
- Cloudy or foul-smelling urine
- Fever and chills
- Nausea and vomiting
Are all stomach aches related to kidney stones?
How are kidney stones diagnosed?
If you report symptoms of kidney stones, your doctor may first enquire about the details of your symptoms, your previous medical history and the list of medicines you are taking. Your doctor will examine you and advise the following tests –
- Blood tests – For detecting infections, evaluating your kidney’s functioning and detecting any possible factors such as too much calcium or uric acid that can be contributing to kidney stones
- Urine tests – To analyse the quantity of urine, presence of blood, the composition of urine and signs of infection
- Imaging – You may be advised to take an ultrasound, X-ray or CT to understand the location, size and shape of your stones
- Analysis of stones – You may be asked to urinate through a strainer. The stones thus collected would be analysed in the lab to find out the composition. This helps in understanding the underlying cause of the stone formation and further treatment planning to prevent stone formation
What are the treatment options for kidney stones?
Smaller stones which are less than 5mm may pass through the urine on their own with the help of medicines. You may be advised to drink a lot of water (around 2 to 3 litres every day). The medicines prescribed include –
- Allopurinol (for uric acid stones)
- Medicines that promote urination (Diuretics)
- Antibiotics (to treat urinary tract infections)
- Phosphate solution (prevents the formation of calcium stones)
- Sodium citrate or bicarbonate (decreases the acidity of urine)
- Pain relief medicines
- Medicines to prevent vomiting
In some cases, the stone may be huge, block the passage of urine and lead to infections. In such cases, they are removed through surgical procedures. The procedures for removing huge stones include –
- Extracorporeal shock wave lithotripsy (ESWL) – Ultrasound shock waves are directed towards the stones to produce strong vibrations. The strong vibrations cause fragmentation of the stones which are removed through the urine
- Percutaneous nephrolithotripsy (PCNL) – A small incision is made in your flank area through which a tube is passed to the kidney under X-ray guidance. A telescope and other instruments are then passed through this tube and used for breaking the stone and removing it. Patients undergoing this procedure experience less postoperative pain, are discharged more quickly and resume work and daily activities sooner
- Ureteroscopy – Your doctor inserts a thin tube containing a camera (called a ureteroscope) into your ureter via your urethra and bladder. After detecting the stone, it is broken into small pieces and the pieces are removed with small instruments. Then a small tube (stent) is placed temporarily to relieve swelling and promote healing
What are the complications of kidney stones?
- Infections that lead to the collection of pus in kidneys (renal abscess)
- Severe infection that spreads in the blood and is life-threatening (sepsis)
- Scarring and perforation of the ureter
- Leakage of urine due to perforation or rupture of the ureter. (Urine extravasation)
- Loss of kidney function
- Painful retention of urine if the bladder is blocked by a stone
Can kidney stones recur?
Renal stones are likely to recur if the underlying risk factors are not addressed. There is around a 50% chance of recurrence of stones within 5 years. Ensure that you are drinking plenty of water and following a kidney-friendly diet with less salt and animal proteins.
I have kidney stones. What dietary and lifestyle modifications should I make?
- Drink plenty of water – This helps flush out excessive minerals and salt from the body
- Reduce the consumption of animal proteins – Animal proteins promote the formation of uric acid stones. Hence, it is advisable to replace animal proteins with plant-based proteins
- Restrict salt intake and limit intake of food that contains high amounts of salt
- Avoid overconsumption of calcium, vitamin D and C supplements. Rely on dietary sources for these
- Limit intake of food substances high in oxalates such as spinach, lady’s finger (okra), baked potato etc
- Maintain healthy body weight through diet modifications and regular exercise
How do I prevent kidney stones?
You can reduce your risk of developing the condition through the following ways –
- Drink plenty of water (unless your doctor says otherwise). Make it a point to consume at least 2 litres of water every day
- Have a healthy balanced meal. Limit your intake of sugar, salt and red meat
- Make regular exercise part of your life to maintain a healthy body weight