Overview
- Major component of bones and teeth (80-85% of phosphorus is bound there).
- Major intracellular anion.
- Also important in energy metabolism and acid-base balance.
- Parathyroid hormone is main regulator - excreted through kidneys.
- Marker of bone disease, parathyroid function and renal function.
Uses
In combination
Result data
Normal (reference) values
UK
- 0.8-1.6 mmol/l (mEq/l).
- 2.5-6.0 mg/dl.
- Conversion factor: g/dl x 0.3229 → mmol/l.
Abnormal values
Hyperphosphatemia
- High phosphate diet (meat/offal).
- Chronic renal failure
. - Acute renal failure.
- Fanconi's disease
(Basenji
). - Renal cortical hypoplasia
(Cocker Spaniel)
. - Nephropathies (in Dobermann
and Soft Coated Wheaten Terrier 
- Osteolytic bone neoplasia
. - Hypervitaminosis D (calciferol poisoning
). - Bladder rupture
. - Phosphate enema toxicity.
- Intravascular hemolysis.
- Tumor cell lysis.
- Metabolic acidosis
.
- Administration of oral phosphate-binding agents, eg aluminium hydroxide.
- Hypercalcemia of malignancy
. - Primary hyperparathyroidism
. - Hyperadrenocorticism
. - Treatment of diabetic ketoacidosis
. - Eclampsia
. - Carbonic anhydrase inhibitors.
- Renal tubular disorders.
- Respiratory alkalosis.
- Hyperthermia.
- Vitamin D deficiency.
Errors and Artifacts
False increase- Hemolysis or prolonged contact of serum with cells resulting in shift of phosphorus from inside cells into serum.
- Varies according to age and breed.
- Young dogs have high phosphorus.
- Hemolysis may result in artefactual increase.
Sources
Publications
Other sources of information
- Ettinger S J & Feldman E C (eds) (2000) Textbook of Veterinary Internal Medicine. 5th edn. Philadelphia: W B Saunders & Co.
- Kaneko J J, Harvey J W & Brass M L (eds) (1997) Clinical Biochemistry of Domestic Animals. 5th edn. Boston: Academic Press.
- Duncan J R, Prasse K W & Mahaffey E A (1994) Veterinary Laboratory Medicine. Clinical Pathology. 3rd edn. Iowa: Iowa University Press.



