Kidney Stones: Symptoms, Causes & Treatment

Kidney stones are hardened masses that form inside the kidneys and can move through the urinary system. They may feel like severe lower back pain that spreads to the groin, and can also cause nausea, vomiting, painful urination, blood in the urine, and fever.

The risk of kidney stones may be higher with low fluid intake, genetic predisposition, or a diet high in sodium, protein, potassium, phosphorus, or calcium. Stones may be made of calcium oxalate, calcium phosphate, uric acid, struvite, or cystine.

Treatment for kidney stones depends on the size, location, and type of stone, as well as symptoms. A kidney specialist or urologist may recommend medications, diet changes, or procedures to break up or remove the stone, depending on its size and location.

Main symptoms

The main kidney stone symptoms are:

• Lower back pain that can limit movement

• Back pain that may radiate to the groin

• Blood in the urine or cloudy urine, in some cases

• Frequent urge to urinate

• Pain when urinating (dysuria)

• Fever

In addition, if the urinary tract becomes blocked, urine flow may stop, increasing pain and discomfort.

Symptoms of kidney stones are more likely when the stone is large or moving through the urinary system, and their intensity can vary depending on the stone’s location.

How to pass a kidney stone

A kidney stone may pass on its own, depending on its size and location. Smaller stones are more likely to pass through the urine, while larger stones may require medical treatment.

According to the National Institute of Diabetes and Digestive and Kidney Diseases, drinking plenty of fluids and taking pain-relief medication may be recommended when a kidney stone can pass on its own. A doctor may also recommend an alpha-blocker, such as tamsulosin, to help some ureteral stones pass more easily.

Medical care is needed for severe pain, fever, vomiting, blood in the urine, or difficulty urinating.

Online symptom quiz

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Confirming a diagnosis

Kidney stones are diagnosed by a nephrologist, urologist, or primary care provider based on symptoms and imaging tests, such as an abdominal ultrasound or CT scan.

These tests can also help identify the size and location of the stone. This information is important for choosing the most appropriate treatment.

The provider may also order a urine test to check electrolyte levels in the urine and identify the composition of the stone. This can help guide treatment more accurately.

Types of kidney stones

Kidney stones can be made up of different substances, such as calcium, uric acid, cystine, or struvite.

The main types of kidney stones are:

• Calcium oxalate stones: The most common type of kidney stone, usually associated with increased intake of high-oxalate foods and increased calcium and oxalate levels in the urine.

• Calcium phosphate stones: Stones formed from calcium and phosphate, often linked to metabolic or urinary conditions

• Uric acid stones: Diamond-shaped stones mainly associated with a high-protein diet.

• Struvite stones: Also called ammonium magnesium phosphate stones, these stones typically develop due to bacterial infections.

• Cystine stones: Stones caused by an inherited (genetic) condition that leads to excess cystine in the urine, making crystals more likely to form.

The type of kidney stone is identified by a healthcare provider through diagnostic tests, which helps guide the most appropriate treatment and ways to prevent new stones from forming.

What causes kidney stones?

Risk factors for kidney stones include:

• Low fluid intake, which makes the urine more concentrated

• A diet high in protein and/or sodium and low in fiber

• Recurrent urinary tract infections (UTIs)

• Genetic predisposition

• Inflammatory bowel disease

• Hyperparathyroidism

• Obesity and a sedentary lifestyle

• Frequent use of aspirin, antacids, and diuretics

Kidney stones can also be caused by rare conditions, such as primary or secondary hyperoxaluria. These conditions can cause oxalate to build up in the body, increasing the risk of kidney stone formation.

Kidney stone treatment

Treatment for kidney stones varies according to the size and location of the stone, its composition, and the severity of symptoms.

The main treatments for kidney stones are:

1. Medication

Pain medications, such as diclofenac, acetaminophen, tramadol, or ketorolac, may be recommended or prescribed to help relieve an episode of renal colic.

Another medication the doctor may recommend is tamsulosin, which works by relaxing the muscles of the ureter. This can help stones that are 4 to 10 mm pass more easily when they are in the ureter.

The doctor may also prescribe medications, such as hydrochlorothiazide or chlorthalidone, to help prevent calcium-based kidney stones.

2. Surgery

Surgery for kidney stones is recommended for stones larger than 6 mm or when a stone is blocking the passage of urine. It can be performed using different techniques, depending on where the stone is located.

These techniques include extracorporeal shock wave lithotripsy, percutaneous nephrolithotomy, and ureteroscopy.

3. Diet

A kidney stone diet should be guided by a registered dietitian. Foods with a high water content, such as cucumber, squash, or watermelon, are generally recommended, along with increased water intake, to help the stone pass.

Limiting salt and reducing daily protein intake may also help prevent kidney stones from forming.

4. Natural treatments

Home remedies for kidney stones, such as drinking chanca piedra tea or hibiscus tea, may help increase urine volume and make it easier for the stone to pass. These teas may also have anti-inflammatory properties, which can help relieve symptoms.

However, it is important to emphasize that natural treatment does not replace the treatment recommended by a healthcare provider. A nephrologist can help identify why kidney stones are forming and recommend ways to prevent new episodes.