Urinary Stones - Urolithiasis

The development of urinary stones is most commonly related to:
Decreased urine volume
Increased excretion of stone-forming components
Inadequate urine drainage, which may lead to stasis
Decrease in urinary citrate levels leading to deposition of calcium
Deficiency of vitamins a or c - these conditions can also lead to the" hyper triad: hyperparathyroidism, hypercalcaemia, and hyperuricosuria.

Treatment
When a stone causes no symptoms, watchful waiting is a valid option. For symptomatic stones, pain control is usually the first measure, using medications such as nonsteroidal anti-inflammatory drugs or opioids. More severe cases may require surgical intervention. For example, some stones can be shattered into smaller fragments using extracorporeal shock wave lithotripsy. Some cases require moreinvasive forms of surgery. Examples of these are cystoscopic procedures such as laser lithotripsy or percutaneous techniques such as percutaneous nephrolithotomy. Sometimes, a tube (ureteral stent) may be placed in the ureter to bypass the obstruction and alleviate the symptoms, as well as to prevent ureteral stricture after ureteroscopic stone removal.

Prevention
Recurrence of renal stones is common and therefore patients who have had a renal stone should be advised to adapt and adopt several lifestyle measures which will help to prevent or delay recurrence:
Increase fluid intake to maintain urine output at 2-3 litres per day.
Reduce salt intake.
Reduce the amount of meat and animal protein eaten.
Reduce oxalate intake (foods rich in oxalate include chocolate, rhubarb, nuts) and urate-rich foods (eg, offal and certain fish).
Drink regular cranberry juice: increases citrate excretion and reduces oxalate and phosphate excretion.
Maintain calcium intake at normal levels (lowering intake increases excretion of calcium oxalate).
Depending on the composition of the stone, medication to prevent further stone formation is sometimes given - eg, thiazide diuretics (for calcium stones), allopurinol (for uric acid stones) and calcium citrate (for oxalate stones).