Who is at risk for kidney stones?
- Urinary tract stones are more prevalent in men than in women. According to estimates, approximately 12% of men and 7% of women in the U.S. are likely to develop stones in the urinary tract at some point in their lives.
- People in the age group of 20-49 years, and those who are vulnerable to multiple attacks of kidney stones.
- People who already had suffered from more than one kidney stone.
- People who have a family history of kidney stones
- Kidney stones are highly common in Asians and Caucasians when compared to Native Americans, Africans, or African Americans.
- Uric acid kidney stones are common in people who are suffering from Hyperuricemia; a medical condition in which a person has high uric acid levels in the blood.
- Pregnant women may develop kidney stones. This is mainly due to pregnancy-related changes including increase in the progesterone levels, reduced fluid intake, decrease in the capacity of the bladder due to the enlarged uterus and a slight increase in excretion of calcium in urine.
- Significant reduction in the volume of urine
- Excessive stone-forming materials in the urine. A typical kidney stone consists of calcium in combination with oxalate or phosphate. Certain other chemical compounds which can form stones in the urinary tract are uric acid, magnesium ammonium phosphate and the amino acid, cystine.
- Dehydration caused by reduced consumption of fluids or rigorous exercise without sufficient fluid replacement.
- Severe obstruction to the flow of urine.
- Change in climate: The inhabitants of hot and dry regions are more likely to become dehydrated and are vulnerable to stone formation.
- Infection in the urinary tract can result in struvite or infection stones.
- Inherited metabolic abnormalities
- Different kinds of medical conditions such as Gout, Hypercalciuria, Hyperparathyroidism, Renal tubular acidosis, inherited metabolic conditions such as cystinuria and hyperoxaluria, diabetes and high blood pressure
- People suffering from inflammatory bowel disease
- Individuals who have undergone intestinal bypass or Ostomy surgery.
- Certain medications including some diuretics, calcium-containing antacids, and indinavir (Crixivan), a drug used for the treatment of HIV infection.
- Dietary factors such as insufficient intake of fluids that results in dehydration, high consumption of animal protein, a diet rich in salt, excessive consumption of sugar, excessive intake of vitamin D supplementation and excessive consumption of foods rich in oxalate such as spinach.
- Sometimes, decreased levels of consumption of dietary calcium may change the calcium-oxalate balance, resulting in increase in the excretion levels of oxalate and the potential to form oxalate stones.
Signs and Symptoms
- Sudden and severe cramping pain in the low back and/or side, groin, or abdomen.
- The abdominal, groin, and/or back pain usually increases and decreases in severity. Sometimes, the pain may be so intense that it could be accompanied by nausea and vomiting.
- Presence of blood in the urine.
- If there is infection in the urinary tract along with the stones, it could cause fever and chills.
- Difficulty in urinating, urgency to urinate, penile pain, or testicular pain may happen due to kidney stones.
Diagnosis of kidney stones
Imaging tests are generally done to confirm the diagnosis. The most common test which is performed for detecting stones or obstruction in the urinary tract is the helical CT scan without contrast material. It is a highly effective diagnostic tool.
However, in pregnant women or those who need to avoid the powerful exposure to radiation, an ultrasound examination may be performed for the diagnosis.
Treatment for Kidney stones
In most cases, kidney stones pass through the urinary tract on their own within a period of 48 hours if plenty of fluid is consumed and the body is kept hydrated. During this period, certain medications and anti-inflammatory drugs are prescribed for alleviating the pain. Intravenous pain medications can be administered if the patient suffers from nausea and vomiting.
There are various factors which influence the ability of a kidney stone to pass through the urinary tract. These mainly include the size and weight of the person, the size of the stone, prior stone passage, prostate enlargement and pregnancy. A 4 mm stone usually has an 80% chance of passage while a 5 mm stone only has a 20% chance. Stones which are larger than 9 mm-10 mm can pass only with specific treatment. Certain medications such as calcium channel blockers and alpha blockers have been used to enhance the passage rates of kidney stones.
If the kidney stones do not pass on their own, a procedure known as lithotripsy is generally used. In this process, shock waves are used to disintegrate a large stone into smaller pieces so that they can pass through the urinary system.
How can kidney stones be prevented?
Here are a few general guidelines you can follow to prevent kidney stones:
Drink plenty of water
Based on the cause of the kidney stones and a person’s medical history, dietary changes or medications are usually recommended to reduce the likelihood of developing kidney stones.
If you have a tendency to form calcium oxalate kidney stones, it is better to cut down on foods rich in oxalate, such as spinach, rhubarb, swiss chard, wheat germ, and peanuts.