Kidney or Renal Stones
Kidney stones are also known as Renal stones or renal calculi. They are made up of different types of crystals. The usual site of their origin is kidneys, but they might migrate to any part of the urinary tract; ureter, bladder or urethra. They are usually painful and may present as an acutely painful condition, requiring immediate medical intervention.
- Oxalate stones: They are the commonest type of kidney stones. A diet low in oxalate can help in preventing development of this type of renal stones. Food items that are rich in oxalate are spinach, cocoa, beet etc. Most of the stones are originated from oxalate, good amount of dietary consumption of calcium reduces the risk of developing calcium stones.
- Uric Acid Stones: These are commoner among males as compared to their female counterparts. People diagnosed with gout are more likely to develop this type of stones. Patients on chemotherapy are at high risk of developing this type of stones. Excessive acidity in the urine often predisposes to this type of stones. A purine rich diet tends to increase the acidity of urine, this is found in animal proteins mainly, like some fishes and meats.
- Struvite stones: Women having urinary tract infections are at risk of developing struvite stones. This form of stones can be large and may cause obstruction of the urinary tract. They usually result from infections in the kidney. Treatment of the underlying infection can help in reducing the chances of developing this form of stones.
- Cystine stones: Cystinuria is a genetic defect that leads to leaking of cystine from the kidneys into urine. This leads to the chances of developing cystine stones.
- Less consumption of water, and hence less production of urine increases the chances of renal stones.
- Males are more likely to develop renal stones
- Past history of renal stones
- Inflammatory bowel disease
- Certain medications like diuretics, anti-seizure drugs, etc.
- High Salt intake
Acute pain is one of the most important manifestation of renal stones. The pain is usually felt when the stone starts migrating from the kidneys to the ureters. The pain may be felt in the affected side of the abdomen or back. In males, the pain may radiate to the groin area. The pain may be felt on and off or may be continuous. Other important symptoms of renal stones are:
- Haematuria or blood in urine
- Frequent urge to urinate
In some cases, the stones may be too small and may pass down the ureter and eventually through the urethra without any pain. For cases where the stones are considerably larger, they may cause obstruction of urine in the ureter leading to infection in the kidneys. When stuck in ureters, the stone may irritate the walls and cause pain and bleeding.
Diagnosis of a renal stone can be made through a complete physical examination along with some basic radiological and blood examinations:
- X-ray abdomen
- Kidney function tests
- Urine routine and microscopic examination
- Intravenous pyelogram
- Retrograde pyelogram
- Ultrasound of kidneys
- MRI abdomen
- CT Abdomen
The line of treatment is decided depending upon the type of stone. Increasing water intake to up to 10 to 12 glasses can help in keeping the patient well hydrated, especially in case of nausea and vomiting.
Pain killers may be prescribed to subside the pain to some extent. Antibiotics are given for treatment of infection when the same is the underlying cause.
Extracorporeal Shock Wave Lithotripsy is a procedure where sound rays are used to dissolve the stones and break them into smaller fragments. This is usually conducted under anaesthesia.
In some cases, a percutaneous nephrolithotomy may be advised where a hole is made in the lower back to remove the stones with the help of an endoscope.
Ureteroscopy may be done in many cases to visualize and remove the stone.
Adequate water intake is the key to prevention of renal stones. Reducing intake of food rich in oxalate and increasing citrate intake can help in reducing certain types of stones. Keeping salt in diet low and maintaining a healthy weight are very helpful.