Kidney Stones: Causes, Types, Symptoms and Diagnosis

What is Kidney Stone?

Kidney stone is a medical condition that happens due to the crystallisation of minerals present in the urine. The stone are hard, stone-like deposits of salt and minerals, and can develop anywhere in the urinary tract but they are most common in the kidneys or ureter. Although not a life-threatening condition, it can cause some uncomfortable symptoms, particularly pain and discomfort in the belly and back area, nausea, and blood in the urine, hence it requires timely treatment. kidney stones can be prevented by drinking plenty of fluids every day.

Types of Kidney Stones

Following are the types of kidney stones —

1. Calcium oxalate stone

This is the most common form of kidney stone. Calcium oxalate stones form when calcium combines with oxalate in the urine. Consuming foods high in oxalate, such as black tea, beetroots, spinach, sweet potatoes, and nuts, increases the risk of calcium oxalate kidney stones.

2. Calcium phosphate stone

Certain metabolic conditions and medications can cause calcium phosphate kidney stones. Problems with functioning of the urinary system and kidneys can also lead to calcium phosphate stones in the urinary tract.

3. Uric acid stones

These stones are common in people who consume a high-protein diet or have diabetes or metabolic syndrome. Some cases of uric acid stones are also related to excessive loss of fluid from the body due to chronic diarrhoea or malabsorption. A family history of uric acid stones is also a risk factor.

4. Struvite stones

Struvite stones form due to certain types of urinary tract infections. These stones grow rapidly and are more common in women. If left untreated, struvite stones can occupy a large part of the kidney and lead to loss of kidney function.

5. Cystine stones

These stones are common in people with a hereditary condition called cystinuria. The condition leads to accumulation of amino acid cystine in the urine. This amino acid causes stones to form in the kidneys as well as other parts of the urinary tract.

Causes of Kidney Stones

One of the main factors that leads to the formation of kidney stones is the concentration of crystal-forming substances in the urine. High amounts of these substances in the urine, such as calcium, uric acid, and oxalate, can prevent the fluid in the urine from diluting. In some cases, the urine lacks substances that prevent crystallisation or the crystals from sticking together. This leads to the formation of kidney stones.

Kidney stones can also form due to various other factors, including:

1. Dehydration

Drinking less or not enough water can lead to concentrated urine, which increases the risk of stone formation.

2. Genetics

A family history predisposition can increase the risk and likelihood of developing kidney stones.

3. Diet

High intake of a diet rich in protein, sodium (salt), and sugar can contribute to the development of kidney stones.

4. Pre-existing medical conditions

Certain health conditions such as hyperparathyroidism, UTI, and cystic kidney diseases can increase the risk of developing kidney stones.

5. Obesity and certain surgeries

These factors can also increase the likelihood of developing kidney stones.

6. Certain medications

Medicines like diuretics, antacids containing calcium can increase the level of substances that form stones.

Symptoms of Kidney Stones

Kidney stones can cause a range of mild to severe symptoms, such as:

• Severe pain in the side and back, particularly below the ribs
• Pain in the lower abdomen and groin
• Intermittent pain that fluctuates in intensity
• Pain and discomfort while urinating
• Urinating more often
• Passing small amounts of urine
• Cloudy or foul-smelling urine
• Passing red, pink, or brown urine due to the presence of blood in it
• Fever and chills in case of infection
• Feeling sick or nauseous
• Vomiting

Diagnosis of Kidney Stones

Kidney stones are diagnosed in the following ways:

1. Blood tests

Blood tests are done to check the level of calcium or uric acid in the blood. The tests can also help check the health and function of your kidneys.

2. Urine test

This is done to check the presence of too many stone-forming materials in urine.

3. Imaging tests

These are done to check if stones are present in the urinary tract. Instead of simple X-rays, doctors recommend high-speed CT scans to detect both big and small stones.

4. Analysis of kidney stones

The doctor may also analyze the stones present in urine to understand what is causing them and how to prevent the condition.

Treatment Options for Kidney Stones

The treatment for kidney stones depends on the size and type of stones and their causes.

1. Small kidney stones

If the stones are small and you are experiencing minimum symptoms, the condition can be treated in the following ways —

• Drinking more water: Drinking about 2.5 to 3.5 litres of water a day can help you get rid of small kidney stones through urine.
• Taking prescribed medicines: Your doctor may prescribe certain medications to relax the muscles in the ureter and help pass kidney stones more easily.
• Taking painkillers: Small kidney stones can cause pain and discomfort, especially when you are being excreted from the body. To relieve this pain, your doctor may prescribe a mild painkiller.

2. Large kidney stones

Large kidney stones may not pass on their own, so they are usually removed in the following ways —

• Sound waves: Sound waves are used to break stones into small pieces so they can be easily passed in the urine.
• Surgery: A small incision is made in the back to remove the stone surgically.
• Ureteroscope: A lighted tube (i.e., Ureteroscope) is used to locate the stone. Once the stone is located, doctors use special tools to break it into small pieces that will pass in urine.

Prevention of Kidney Stones

A) Lifestyle Tips

The following are some simple lifestyle tips that can help prevent kidney stones —

• Increase your fluid intake: Drink water and other fluids throughout the day to increase urine output. This is important to dilute urine and prevent the formation of kidney stones.
• Consume less oxalate-rich foods: High consumption of oxalate-rich foods and beverages can significantly raise your risk of forming calcium oxalate stones. Therefore, it is wise to restrict the intake of foods and beverages rich in oxalate, such as spinach, beetroot, sweet potato, black pepper, tea, and okra, especially if your kidneys tend to form calcium oxalate stones.
• Consume less salt and animal protein: Reduce your salt intake and opt for non-animal sources of protein, such as legumes.

B) Diet and Nutrition Recommendations

The following are some important diet and nutrition recommendations for kidney stones:

• Drink at least 2.5 litres of fluids every day.
• Limit the consumption of oxalate-rich foods.
• Consume more calcium-rich foods but avoid calcium supplements.
• Limit your protein intake, as excess protein will increase urinary excretion of oxalate and lead to calcium oxalate kidney stones.
• Limit your intake of salt to decrease your chances of developing stones.
• Do not take high doses of vitamin C supplements.

Complications & Risks Associated

Kidney stones can lead to several complications and risks, especially if left untreated. It also depends on the size and location of the stones and whether they are causing obstruction. Here are the main complications- associated with kidney stones:

1. Experiencing severe pain

This is one of the most common complication. The pain is typically experienced in the back or side, which can also radiate to lower abdomen and groin. The pain can be excruciating and may require medical assistance for relief.

2. Obstruction of urine flow

Kidney stones can restrict or block the normal flow of urine, leading to hydronephrosis i.e. swelling of the kidneys and potentially causing damage to the kidney over time, if not treated promptly.

3. Damage to the kidney tissue

Recurrent or persistent stones can cause damage to the kidney affecting its function and potentially leading to chronic kidney disease.

4. Infection

A blocked kidney can lead to urinary tract infection (UTIs) which may require antibiotics and further management.

5. Urinary complications

Stones in the urinary tract can cause either frequent urge to urinate, or difficulty in urinating, or blood in the urine i.e. hematuria.

6. Complications during pregnancy

Kidney stones during pregnancy can lead to complications such as preterm labor, low birth weight, or hypertension if not managed carefully.

7. Increased risk of future stones

Once an individual has had a kidney stone, they are at a higher risk of developing another stone in future.

Conclusion

To sum up, kidney stones can cause immense pain and discomfort as well as affect your quality of life. Moreover, severe cases of the condition can lead to complete loss of kidney function. Therefore, it’s important for individuals who have had kidney stones or are at risk for them to work closely with healthcare providers to manage their condition through certain lifestyle modifications and dietary adjustments, and sometimes medications to reduce the risk of complications. Early recognition and management of symptoms are crucial in preventing risks associated with kidney stones.

Source: kidneyfund, nyulangone, mayoclinic, betterhealth, kidneystonemelbourne, kidney.org