The tubular reabsorption of phosphate (TRP) is a calculated parameter which gives information about phosphate handling by the kidney. The TRP is the fraction of filtered phosphate which is reabsorbed by the tubules.
SPECIMENS: 5 mL blood in a heparin tube for phosphate (Pp) and creatinine Cp) and a random urine in a plain container for phosphate (Pu) and creatinine (Cu).
| TPR = 1 - (Pu x Cp) / (Pp x Cu) |