Urinary Stones

The lifetime prevalence of kidney stone disease typically ranges from 1% to 15%. While it is relatively uncommon in individuals under 20 years of age, it is two to three times more prevalent in men than in women. The condition is more common in hot, dry, and arid climates such as mountains, deserts, and tropical regions. In India, kidney stones are particularly prevalent in the northern regions and the Deccan Plateau. Additionally, the incidence of stone disease shows seasonal variation, with the highest occurrence during the summer months. The risk of developing kidney stones also increases with body weight.

Around three-fourths of kidney stones are composed of calcium, making them visible on X-rays. Calcium oxalate stones are the most common type in India, accounting for approximately 93% of cases. Non-calcium stones, such as struvite (infection-related stones) and uric acid stones, are also present. Uric acid stones, however, are not visible on a standard X-ray but can be detected through a CT scan.

How Can We Suspect Stone Disease?

Kidney stones typically present with severe pain, often starting in the flank region and radiating down to the groin or genital area. This pain can be intense, and the patient may feel nauseous or even vomit. Despite tossing and turning in bed, the pain remains unrelieved. Other symptoms may include a burning sensation while urinating, frequent urination with small amounts of urine, and occasionally blood in the urine. A fever with chills is a serious sign of infection and should not be ignored.

In some cases, kidney stones may silently damage the kidney, causing significant complications. A stone may block the drainage from the kidney, leading to hydronephrosis (swelling of the kidney). In extreme cases, this can result in complete loss of kidney function.

How Is the Diagnosis of Stone Disease Made?

When there is a suspicious history or non-specific abdominal pain, diagnostic tests are needed to confirm the presence of kidney stones. Stones larger than a few millimeters can often be detected using ultrasound and X-rays. However, these methods have certain limitations and may miss smaller stones. A plain CT scan of the abdomen is highly accurate, with up to 98% sensitivity in detecting even the smallest stones, including those that may not be visible on X-rays. For proper evaluation, patients may require specialized radiological tests such as IVP (Intravenous Pyelogram) or CT-IVP before considering any surgical intervention.

When Should Kidney Stones Be Treated?

While kidney stones are common, many smaller stones or crystals pass through the urinary system without causing major problems. However, as the size of the stone increases or as it moves further from the bladder, the likelihood of spontaneous clearance decreases. Small renal stones located on the periphery of the kidney can often be safely monitored with periodic ultrasound examinations. However, some stones require surgical removal if they cannot be managed with observation or medication.

Indications for Treatment

• Small stones obstructing urine flow from the kidneys
• Large (staghorn) stones in the kidneys
• Stones in the upper ureter causing pain
• Ureteral stones greater than 5 mm causing pain
• Bladder stones larger than 1 cm
• Stones in a single kidney (whether congenital or following the removal of the opposite kidney)
• Infected stones
• Recurrent urinary tract infections (UTIs) due to stones
• Stones in individuals working as pilots or in the military, where frequent movement or strain is involved