Kidney stones
What are kidney stones?
Your kidneys play an important role in filtering blood and removing extra water and waste products (chemicals) that are passed through the body as urine. Sometimes these chemicals can clump together as solid crystals known as kidney stones (also called renal calculi). Kidney stones are one of the most common disorders of the urinary tract. Kidney stones can be of varying shapes and sizes, ranging from the size of a grain of sand to a golf ball. Some can be extremely painful and have the potential to block the flow of urine and cause other serious complications.
Anyone can develop kidney stones, but they are more common in men than in women. The lifetime risk of developing them is one in 10 men, and one in 35 women. At any one time, 4-8% of Australians will have kidney stones.
Kidney stone symptoms
Symptoms of kidney stones are not usually obvious unless they move from where they were first formed and pass into your ureters (tubes that connect the kidneys to your bladder).4If a stone lodges in your ureters it can block the flow of urine, which is when you’re most likely to experience symptoms.
The most common symptom is pain known as ‘renal colic’. This pain usually occurs in your side and back, just below your ribs and it may:
be severe, sharp or gripping
radiate to the lower abdomen and groin
come in waves, or fluctuate in intensity
have a burning sensation when urinating
Other symptoms of kidney stones may include:
nausea and vomiting
blood in your urine
fever with hot and cold sweats
cloudy or bad-smelling urine
small stones that resemble gravel in your urine
feeling like you need to urinate urgently
reduced amount of urine flow (flow that stops entirely is a medical emergency)
What causes kidney stones?
There is no single, definite cause of kidney stones but there are several factors that can increase your risk. These include:
not drinking adequate amounts of water
high levels of substances such as calcium, oxalate, cystine acid or uric acid in your urine
underlying medical conditions such as:
o urinary tract infection (UTI)
o diseases of the digestive tract
o inflammatory bowel disease
o hyperparathyroidism
o sarcoidosis
o some cancers
o gout
o high blood pressure
o obesity
medications such as antiviral drugs, or those to treat kidney disease, cancer or HIV
eating foods high in salt
having had previous kidney stones
having a family history of kidney stones
Types of kidney stones
There are four types of kidney stones. Knowing the type of kidney stone you have may help determine the cause and treatment, and help you reduce the risk of developing further stones in the future. The four types of kidney stones are:
1. Calcium stones
The majority of kidney stones are calcium stones which are made up of calcium and oxalate, or calcium and phosphate.
2. Struvite stones
These usually occur after a urinary tract infection and are usually large, horn-shaped stones.
3. Uric acid stones
These stones are usually in people who lose too much fluid due to chronic diarrhoea or malabsorption, or in people who eat high-protein diets or have diabetes or metabolic syndrome.
4. Cystine stones
Cystine stones are rare and look more like crystals than stones. They usually occur in people with a hereditary disorder.
How are kidney stones diagnosed?
Sometimes kidney stones can be found by chance during tests for other health conditions. However, if your doctor suspects you have a kidney stone, you may undergo several tests which include:
urine and/or blood tests
ultrasound
CT scans
X-rays, including an intravenous pyelogram (IVP) where a contrast dye is injected into your bloodstream before the x-ray to evaluate the kidneys, ureters and bladder
If you pass a stone while urinating, collect it if possible and take it to your doctor for analysis. This can help determine what kind of stone it is, how to treat it and steps to take to help prevent more from forming.
How are kidney stones treated?
Most of the time, kidney stones will pass on their own within three to six weeks. During this time, you should drink adequate amounts of water to help flush them through. It may be necessary to take pain relief medication during this time, although if the pain is severe, you may be admitted to hospital where stronger pain relief can be given to you.
If stones are too large to pass through, or they block the flow of urine or cause bleeding or an infection, other treatments may be necessary. These include:
Ultrasound treatment to break down the kidney stone into smaller pieces so they can pass through. This is usually used for stones that are less than 2cm in size
A small surgical procedure to remove the stone via a small incision in your back
A procedure called a ureteroscopy where an instrument (ureteroscope) is inserted through the urethra into the bladder and then into the ureter to where the stone is located. If the stone is small, it may be removed, but if it is large, the stone is broken up into smaller pieces and removed.
What are the complications of kidney stones?
Kidney stones have the potential to cause some serious complications such as acute kidney injury or chronic kidney disease, which is why it’s important to seek medical treatment if you suspect you have kidney stones.
When to see your doctor
If you notice any kidney stone symptoms, consult your doctor. You should seek immediate medical attention if you have:
severe pain that makes it difficult to sit in a comfortable position
pain with nausea and vomiting
pain with fever and chills
trouble urinating
blood in your urine
Can you prevent kidney stones?
There are several lifestyle changes you can make to prevent the formation of kidney stones, including:
drinking plenty of fluids, especially water
limiting drinks that contain phosphoric acid (e.g. cola and beer)
avoiding UTIs and treating them quickly if you develop one
limiting your intake of animal protein such as red meat, poultry, eggs and seafood
drinking fruit juices such as cranberry, orange and grapefruit
including dairy foods in your diet
reducing your salt intake
checking with your doctor before you take calcium supplements
If you have had kidney stones before your doctor may prescribe you medication to be used in combination with lifestyle measures, to prevent further stones from forming. Medication will depend upon the type of stone you had but it may include18:
calcium stones — medication to increase your urine flow
struvite stones — long-term use of antibiotics to prevent UTIs
uric acid stones — medication to reduce uric acid levels and medication to keep your urine alkaline
cystine stones — medication to reduce the amount of cystine in your urine
Kidney stones can be caused by numerous factors, including medication. At MediADVICE we can help you manage your health with a Medication Review, where one of our Pharmacists will review your medication and discuss which ones, if any, may be contributing to your symptoms, and how we can best help you manage them. Our friendly Pharmacists can also provide advice on products that may assist with your symptoms or may refer you to your doctor for further treatment.
Book a Medication Review at MediADVICE today