What is a Kidney Stone?
Kidney stones are hard deposits of minerals and salts that form in the kidneys. They range in size from tiny grains of sand to as large as a golf ball. While small stones can pass through the urinary tract on their own, larger stones may require surgery.
Factors such as diet, excess body weight, certain medical conditions, and specific medications or supplements can contribute to their formation. Kidney stones can affect any part of the urinary tract, including the kidneys and bladder.
Symptoms of Kidney Stone
A kidney stone usually doesn’t cause problems until it starts moving around inside the kidney or moves through the tubes connecting the kidney and bladder.
It might stop urine flow, expand the kidney, and cause painful spasms in the tube connecting the kidney and bladder.
You may then experience the following signs and kidney stone symptoms:
- Pain in the side and back, below the ribcage, is severe and intense
- Pain in the lower abdomen and groin that radiates
- Urinating causes pain or a burning sensation.
- Blood in the urine
- Frequent urge to urinate
- Urinating in small amounts
- Nausea
- Fever and chills
As a kidney stone passes through the urinary tract, the pain it causes may vary—for example, it may migrate to a new spot or rise in intensity.
Types of Kidney Stones
Understanding the type of kidney stone can inform its cause and guide preventive measures. If possible, save the kidney stone and bring it to the doctor for analysis.
Calcium Stones
- The majority of kidney stones are calcium stones, primarily calcium oxalate.
- Oxalate is produced by the liver or consumed through diet and is found in fruits, vegetables, nuts, and chocolate.
Struvite Stones
- Develop due to urinary tract infections.
- It can grow rapidly and become large with minimal warning signs.
Uric Acid Stones
- Associated with high-protein diets, diabetes, metabolic syndrome, chronic diarrhea, or malabsorption.
- Genetic factors may increase risk.
Cystine Stones
- Formed in individuals with cystinuria, a hereditary condition.
- Kidneys excrete excessive amounts of specific amino acids.
What are the causes of Kidney Stones?
Here are some kidney stone causes:
Dehydration
Inadequate fluid intake leads to concentrated urine, promoting mineral crystallization.
Dietary Factors
High intake of sodium, oxalate, and animal proteins, combined with low calcium and fluid intake, increases stone risk by promoting mineral buildup in urine.
Family History
People with a family history of kidney stones are more likely to develop them, suggesting either a genetic predisposition or shared environmental factors that contribute to stone formation.
Medical Conditions
Conditions like urinary tract infections, cystic kidney diseases, hyperparathyroidism, and inflammatory bowel diseases can alter urine composition or kidney function, predisposing individuals to kidney stones.
Obesity
Metabolic changes associated with excess weight increase urinary excretion of calcium, uric acid, and other substances contributing to kidney stone formation.
Risk factors of Kidney Stones
The following factors enhance the chance of getting kidney stones:
Dehydration
- Inadequate water intake raises the risk of kidney stones.
- People in hot, dry areas or those prone to heavy sweating are at higher risk.
Obesity
High BMI, large waist circumference, and weight gain increase the risk of kidney stones.
Digestive Diseases and Surgery
- Inflammatory bowel disease or gastric bypass surgery can disrupt calcium and water absorption.
- This disruption may elevate the concentration of stone-forming chemicals in urine, increasing the risk of kidney stones.
Diagnosis of Kidney Stones
Blood Testing
- Detects excess calcium or uric acid in the blood.
- Helps monitor kidney health and identify potential medical concerns.
Urine Testing
- 24-hour urine collection may reveal abnormal levels of stone-forming minerals or chemicals.
- The doctor may recommend multiple urine samples over consecutive days.
Imaging
- Various imaging tests, including high-speed or dual-energy computerized tomography (CT) and ultrasound, can detect kidney stones.
- Even microscopic stones can be identified.
- Abdominal X-rays are less commonly used.
Treatment Options for Kidney Stones
Small Stones with Minimal Symptoms:
Drinking Water
Adequate hydration (1.8 to 3.6 liters/day) helps dilute urine and prevent stone formation.
Surgery Options for Large Stones
Percutaneous Nephrolithotomy
- Surgery to remove large kidney stones using a small telescope inserted through a small incision in the back.
- Requires anesthesia and hospitalization for recovery.
Ureteroscopy
- Insertion of a thin tube with a camera through the urethra and bladder into the ureter to remove or break up small stones.
- It may require general or local anesthesia.
Prevention of Kidney Stones
Stay Hydrated
Maintain adequate urine volume by drinking plenty of water throughout the day.
Balanced Diet
Consume a diet rich in fruits, vegetables, and whole grains while limiting sodium, animal proteins, and oxalate-rich foods.
Monitor Calcium Intake
Ensure appropriate calcium intake from dietary sources to prevent calcium oxalate stone formation.
Limit Oxalate-Rich Food
Reduce your intake of oxalate-rich foods such as spinach, nuts, and chocolate to lower the risk of stone formation.
Maintain Healthy Weight
Proper diet and physical activity can help you maintain a healthy weight and lower your chance of developing kidney stones.
Kidney stones are a common yet painful condition that requires effective treatment. Symptoms include severe pain in the back or side, blood in the urine, and frequent urination. The causes of kidney stones can vary, including dehydration, certain foods, genetics, or underlying health conditions.
Kidney stone diagnosis is typically made through imaging tests like X-rays or CT scans, along with urine and blood tests. Treatment depends on the size and type of kidney stone and may include medication, lifestyle changes, or procedures like lithotripsy or surgery to remove the stone. Prompt diagnosis and treatment are crucial to managing pain and preventing further complications.
