Dr Tariq Jagnarine
Family Medicine, Endocrinology/ Diabetes
Kidney stones develop when dissolved minerals build up inside the kidneys. A low fluid consumption, dietary factors, and a person’s medical history may contribute to this development. Kidney stones may be small and pass unnoticed through the urinary tract, but some grow to the size of a golf ball. Larger stones can cause severe pain as they leave the body. Without treatment, kidney stones can lead to urinary problems, infections, and kidney damage.
Kidney stones are a common problem throughout the world, and the incidence appears to be growing. Dietary factors and climate change may contribute to this increase, as one study indicates.
CAUSES
There are four different types of stone: calcium, uric acid, struvite, and cystine.
• Calcium stones form when the kidneys retain the excess calcium that the muscles and bones do not use, rather than flushing it out of the body. The calcium combines with other waste products to form crystals such as calcium oxalate, which clump together to make a stone.
• Uric acid stones result from a lack of water in the body. Urine contains uric acid, when there is not enough water to dilute the uric acid, the urine becomes more acidic.
• Struvite stones can form after a UTI. They consist of magnesium and ammonia.
• Cystine stones develop when cystine, a substance present in the muscles, builds up in urine. This occurrence is rare.
The American Urological Association says that people who are susceptible to kidney stones should consume enough fluid to produce 2.5 litres (l) of urine each day. On average, this means consuming close to 3 litres of fluid a day, sourced from foods and beverages.
Apart from dehydration, factors that increase the risk of kidney stones include:
• Family or personal history of kidney stones
• Aged 40 years or older, although they can sometimes affect children
• Sex, as they are more common in males than females
• Diet that is high in protein and sodium
• Sedentary lifestyle
• Obesity
• Diabetes
• High blood pressure
• Pregnancy
• Recent surgery on the digestive system
• Health conditions that affect how the body absorbs calcium, such as inflammatory bowel disease and chronic diarrhoea
• Various medications
SYMPTOMS
Kidney stones do not always cause symptoms. A person may pass very small stones out of the body in the urine without being aware of them.
When symptoms appear, they commonly include:
• Pain in the groin, the side of the abdomen, or both, and to the upper back.
• Blood in the urine
• Vomiting and nausea
• Urinary tract infection that can be recurrent (UTI)
• Fever and chills, if there is an infection
• An increased need to urinate
• Burning sensation
If kidney stones block the passage of urine, a kidney infection may result. The symptoms include:
• Fever and chills
• Weakness and fatigue
• Diarrhoea
• Cloudy, foul-smelling urine
DIAGNOSIS
Various tests can show whether a kidney stone is present. A physical examination may identify the kidneys as the source of pain.
• Urinalysis can reveal blood in the urine, or signs of an infection.
• Blood tests can help identify complications.
• Imaging tests, such as a CT scan or ultrasound, will reveal any structural changes. Imaging tests can help doctors determine:
• Whether a stone is present
• the size and location of any stone
• whether there are any blockages
• the condition of the urinary tract
• whether complications have affected other organs
During pregnancy, an ultrasound is preferable to a CT scan, as it does not involve radiation.
COMPLICATIONS
When kidney stones remain inside the body, complications can develop. If they block the tube that connects the kidney to the bladder, urine will not be able to pass out of the body. This dysfunction increases the risk of a UTI or kidney infection. If recurring kidney stones cause blockages in the urinary system, this can increase the risk of chronic kidney disease. About 50% of people who have had a kidney stone develop another one within 5–7 years.
• Recurrent Kidney Stone
• Urinary Tract Infection
• Urinary Obstruction
• Sepsis
• Kidney Damage- Short term and eventually Chronic if not treated
TREATMENT
Treatment will focus on managing symptoms and removing the stone. There are various ways to do this. Treatment may involve:
• A high intake of fluids by mouth or intravenously
• Pain relief medication
• Medications to help speed up the passage of stones
• Large stones
Large stones may need other types of intervention, such as shock wave lithotripsy, ureteroscopy, or percutaneous nephrolithotomy (PCNL).
• Shock waves involve the use of ultrasound waves to break the stone into smaller pieces to make it easier to pass.
• Ureteroscopy is done by passing a long, thin tube through the person’s urethra as far as the ureter, which connects the bladder and the kidney. They will then use laser energy to break up the stone.
• PCNL involves passing a long, thin instrument through the back and into the kidney, where it can break up or remove the stone using laser energy. This procedure requires general anaesthesia.
There may be a risk of complications, such as an infection, after removing a large kidney stone. A doctor should explain the possible complications beforehand, so that if any develops, a person can recognise the signs.
HOME REMEDIES
A person can usually treat small kidney stones at home. Some recommendations include:
• Drinking plenty of fluid and waiting for the stone to pass
• Using over-the-counter drugs to relieve pain and nausea
• Alpha-blockers to help the stone pass more quickly
• Avoiding salt and sodas
• Continue to drink plenty of fluid after the stones have gone, to prevent new ones from forming.
• Some foods may benefit kidney health and help reduce the risk of kidney stones.
• Herbs and spices- Guidelines from the American Family Physician (AFP) note that people have long used herbal remedies for kidney stones. However, there is uncertainty regarding their safety, effectiveness, and possible interactions with other drugs.
• Chemical compounds in green tea, berries, and turmeric may help prevent infection
• Parsley may boost urine production
• Some research suggests that vitamin D deficiency is common among people with kidney stones, but there is not enough evidence to show that vitamin D supplements are safe or effective for preventing stones.
FOODS TO AVOID
• Limiting foods that contain the following substances may help prevent stones from developing:
• Excessive protein
• Sodium (salt)
• Sugar, such as high fructose corn syrup
• Vitamin C supplements
Kidney stones are a common problem. Not drinking enough fluid is a major causative factor; but dietary habits, obesity, and a sedentary lifestyle can all contribute. Anyone who has symptoms of a kidney stone, urine infection, or kidney infection should seek medical advice to prevent complications from developing.
