What is kidney stone?
Kidney stone is a solid crystal that forms in a kidney when substances that are normally found in urine gets concentrated. Kidney stones vary in size. The small stone may pass on its own, causing little or no pain. A large stone may get stuck along the urinary tract blocking the urine flow and causing severe pain. Kidney stones are one of the most common disorders of urinary tract. Other terms used for kidney stones are urolithiasis, nephrolithiasis or renal calculus.
Kidneys are classified on the basis of their chemical composition as calcium oxalate, calcium phosphate, uric acid, struvite, cystine.
What causes kidney stone?
- Kidney stones are formed when there is decrease in urine volume and or excess of stone forming substances like calcium, oxalate, phosphate etc. in urine.
- Dehydration from reduced fluid intake or strenuous exercise without adequate fluid replacement
- High dietary intake of animal protein, sodium, refined sugars, fructose, excessive intake of oxalate containing foods such as spinach,cola drinks etc
- Obstruction to the flow of urine
- Conditions that can lead to increased risk of kidney stones are:
- Hypercalciuria (high calcium in urine) an inherited condition
- Family history of kidney stones
- Gout, a condition with increased amount of uric acid in blood and urine
- Hyperparathyroidism, a condition in which parathyroid gland releases too much hormone causing increased calcium in blood
- Cystic kidney disease, renal tubular acidosis, cystinuria, hyperoxailuria, inflammatory bowel syndrome
- History of gastro intestinal tract surgery
- Some medications like diuretics, calcium based antacids, the protease inhibitor indinavir (used to treat HIV infections)
What are the symptoms of kidney stone?
- Excruciating intermittent pain radiating from the flank to the groin or to the genital area and inner thigh. This particular type of pain is known as Renal colic, is often described as one of the strongest pain sensation known.
- Urinary urgency
- Nausea and Vomiting
- Burning sensation during urination
How is it diagnosed?
- Urine analysis
- Blood test
- Abdominal X ray
- CT scan abdomen
How to prevent kidney stone?
Preventive strategies include some combination of dietary modifications and medications.
- Increasing fluid intake (2-3 litres of water per day)
- Depending upon the type of kidney stone a person has, Limiting the intake of sodium, calcium, animal protein, oxalate rich foods like spinach
What is the treatment for kidney stone?
Treatment of kidney stones usually depends on their size and what they are made of, as well as whether they are causing pain or obstructing the urinary tract. Small usually pass through the urinary tract without treatment. Still the person may need pain medication and should drink lots of fluids to help the stone to move along.
- Pain control may consist of oral analgesics or intravenous medication depending upon the duration and severity of pain
- Person may be given intravenous fluids if he becomes dehydrated due to vomiting or an inability to drink fluids.
- Some medications like diuretics are used to increase the passage of stones
A person with a larger stone or one that blocks the urine flow causes great pain and may need more urgent treatment:
- Lithotripsy: This procedure breaks up the kidney stone into smaller pieces to pass more readily through the urinary tract.
- Ureteroscopy: This procedure is done to find out or retrieve the stone with a small basket or to break the stone up with laser energy.
- Percutaneous nephrolithotomy: This procedure is to locate and remove the stone.