DR CHEW-LIN YIP | UROLOGIST

Dr Chew-Lin Yip assesses and treats kidney and ureteric stones for patients across Mandurah, Rockingham, Murdoch and the wider Peel and southern Perth region — both after renal colic and when stones are found incidentally on a scan.

Stones form when minerals dissolved in urine crystallise and clump together. They may remain in the kidney without symptoms or move into the ureter, the narrow tube draining the kidney to the bladder, where they can obstruct urine flow.

A stone obstructing the ureter typically causes renal colic: severe pain in the loin, often radiating to the groin and coming in waves, frequently with nausea and vomiting. Patients are often restless with the pain.

Other presentations include blood in the urine, recurrent urinary infection or no symptoms.

Seek urgent assessment at an emergency department if pain occurs with fever or shaking chills, if fluids cannot be kept down, or if there is only one functioning kidney. An obstructed kidney with infection requires same-day treatment.

A non-contrast CT scan of the urinary tract is the standard investigation and shows the size, position and density of a stone. Blood and urine tests assess kidney function and look for infection.

Treatment depends on stone size and position, whether the kidney is obstructed, and whether infection is present.

Conservative management. Many small stones pass with fluids, pain relief and time. Medication may help relax the ureter. Progress is monitored to ensure the kidney does not remain obstructed.

Surgical treatment. Stones that are unlikely to pass, obstruct the kidney or keep causing problems may be treated with telescopic laser surgery, shockwave treatment from outside the body, or, for large kidney stones, surgery through a small tract in the flank. Dr Yip will discuss which approach suits the individual stone.

Urgent drainage. When an obstructed kidney is infected, the priority is drainage with a ureteric stent or a tube placed into the kidney through the back. Definitive stone treatment follows after infection settles.

After one stone, further stones can occur. Prevention starts with drinking enough fluid to keep the urine pale through the day. Dietary measures depend on the stone type. For patients who form stones repeatedly, blood and urine testing may identify an underlying cause that can be treated.