Urine Phosphate
Code:
UPHOS
Sample Type:
Random urine – plain, no preservative
24 hour urine (24 hour collection bottle)
Ref Ranges/Units:
Random urine: 15-50 mmol/L
24 hour urine: 12.9 – 42 mmol/24 hour
Turnaround:
Same Day
Stability:
Adjust to pH 2.0
6 months at 2‑8°C (when acidified)
Special Precautions/Comments:
Additional Information:
Phosphate homeostasis is controlled by vitamin D, fibroblast growth factor-23 (FGF-23) and parathyroid hormone (PTH). Vitamin D acts to increase serum phosphate by increased intestinal absorption. PTH and FGF-23 act to decrease serum phosphate by increasing renal excretion. PTH also increases serum levels by increasing bone resorption.
Urine phosphate is measured to investigate hypophosphataemia. It is measured alongside serum phosphate, serum creatinine and urine creatinine to calculate renal tubular reabsorption of phosphate (TmP/GFR). A low TmP/GFR indicates renal loss of phosphate.
South of Tyne & Wear Pathology Centre
