Kidney Stones

Size is the best predictor: stones under 4mm pass spontaneously in about 80% of cases, 4-6mm pass in roughly 60%, and stones over 6mm rarely pass without intervention. Location matters too — lower ureteral stones (near the bladder) pass more easily than upper ureteral stones. Your urologist will assess size and location on a CT scan and advise whether to wait (with pain relief and high fluid intake — 2-3 litres daily) or proceed to intervention. Alpha-blockers like tamsulosin can help relax the ureter and facilitate passage. If you develop fever during this waiting period, seek emergency care immediately — an obstructed infected kidney is a surgical emergency.

Extracorporeal shockwave lithotripsy (ESWL) uses focused shockwaves from outside the body to fragment stones into small pieces that then pass in the urine. It works best for stones under 2cm in the kidney or upper ureter that are not too dense. It's done as a day procedure without general anaesthesia. Success rate for suitable stones is around 70-85%. ESWL doesn't work well for very hard stones (calcium oxalate monohydrate, cystine), very large stones, or stones in the lower ureter — ureteroscopy or percutaneous nephrolithotomy (PCNL) are alternatives for those situations.

The most important prevention step for any stone type is drinking enough water to produce at least 2-2.5 litres of urine daily — in Indian heat this often means drinking 3+ litres. For calcium oxalate stones (most common): limit high-oxalate foods (spinach, beetroot, nuts, chocolate, tea) but don't restrict calcium — dietary calcium actually binds oxalate in the gut and reduces absorption. Reduce animal protein (meat, fish, eggs) as it raises urine acid and calcium. For uric acid stones: reduce meat and purine-rich foods (red meat, organ meats, shellfish), stay well hydrated, and alkalinise urine if needed. Stone composition analysis after your first stone guides specific prevention.

Surgery removes or fragments the stone but doesn't cure the underlying tendency to form stones — that requires dietary and lifestyle change. Percutaneous nephrolithotomy (PCNL) is a keyhole procedure where a nephroscope enters the kidney through a small back incision to remove large or complex stones; it's highly effective for stones over 2cm. Ureteroscopy uses a thin flexible scope through the urethra to reach and laser-break stones in the ureter or kidney. Both procedures are well established in India. However, without addressing the metabolic reasons why stones form (dehydration, diet, metabolic conditions like hyperparathyroidism), recurrence rates remain high regardless of how the stone was removed.

Yes — and the prevalence in Indian children is rising. Dehydration in a hot climate is the primary driver, combined with diets high in salt and animal protein. Children in the stone belt states are particularly affected. Signs in children include unexplained abdominal or flank pain, blood in urine, and recurrent urinary infections. Paediatric kidney stones warrant full metabolic evaluation because in children there is often an underlying metabolic cause (hypercalciuria, hyperoxaluria, cystinuria) that needs specific treatment, not just general dietary advice. The cornerstones of prevention are the same as adults: high fluid intake and an appropriate low-salt, low-animal-protein diet.