Phosphorus, timed urine

Alphabetical Test listing

Phosphorus, timed urine-206

Phosphorus, timed urine
Inorganic phosphorus
Urine, 24 hr
  1. Measure and record total urine volume
  2. Mix well
  3. Pour an 8 mL aliquot of the well mixed sample into a Urine aliquot transport vial/tube -10mL (AHL)

24 hr urine collection container, no additive


Refrigerated (preferred) - 2 days

Ambient - 1 day

Frozen - 6 months

  • Improper labels (unlabeled or mislabeled)
  • Hemolysis (some procedures)
  • Delay in transport
  • Improper storage temperature affecting results
  • Inappropriate timing of collection
  • Improper container
  • Leaking container resulting in compromised specimen
  • Quantity not sufficient (QNS)
AHL - Chemistry: C
1 day



0.4 - 1.3 g/24 hrs


The human body contains nearly a kilogram of phosphorus. Nearly 80% of this amount is in the form of calcium phosphate salts which are contained in, and give rigidity to, bone. The rest is distributed through all other cells of the body where its role is important and complex. Much of the metabolism of carbohydrates involves esterification of intermediary metabolites with phosphate. In fact, the metabolism of all food terminates in the formation of adenosine triphosphate (ATP). The breakdown of ATP to ADP produces the energy needed for chemical reactions involved in cell function, maintenance, and growth. Phosphate is also an integral part of the structure of the nucleic acids, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) which transfer genetic information.

High urinary phosphorus occurs in primary hyperparathyroidism, vitamin D deficiency, renal tubular acidosis, and with diuretic use. Phosphates are among the substances which may be lost in the Fanconi syndrome. Renal loss of phosphate may itself lead to rickets or osteomalacia. Low urinary phosphorus occurs in hypoparathyroidism, pseudo-hypoparathyroidism, and Vitamin D intoxication.