Clinical Biochemistry

Phosphate (urine)

Test Background
Renal stones affect on average between 12-15 % of Caucasians (this figure varies among other population groups). Recurrence rates of up to 50 % within 5 years are not uncommon. Risk factors for recurrent renal calculi include low urine output, impaired renal function, hypophosphataemia and hypomagnesaemia, in addition to increased uric acid turnover, hypercalcaemia and hyperoxaluria.

Clinical Indications

• Recurrent stone formation and/or family history of stone formation
• Phosphate testing is often performed as a follow-up to an abnormal calcium level and/or related symptoms, such as fatigue, muscle weakness, cramps or bone problems

Reference Range

Sample Required
24 hour urine collection acidified

Sample Volume
24 hour urine collection

Turnaround Time
2 days