Phosphorus P (urine) | Laboratory research

Phosphorus is the second most common mineral in the human body after calcium. It represents 1% of body weight, which means that the adult human body has about 600-700 g of phosphorus. The largest amounts of phosphorus are found in skeletal bone (85% in the form of hydroxyapatite), the rest in the muscles, nerves and blood.

Phosphorus plays an extremely important role in bone formation as well as in maintaining skeletal strength. It is also important for maintaining water-electrolyte balance in the body.

Its absorption takes place through the intestinal epithelium and its homeostasis depends on the kidneys, therefore, changes in phosphate levels are most often caused by impaired renal function.

The kidneys filter excess phosphate from the blood and excrete it in the urine. Consequently, in case of renal pathology, a large amount of phosphate accumulates in the urine.

When to take a phosphorus test?

Determination of urinary phosphorus is recommended to assess renal function, phospho-calcium balance, and nephrolithiasis.

How to prepare for the test?

Patient training is not required.

Research material

desired The first urine of the morning.

Possible interpretation of the results

Concentration of phosphorus in urine increases:

• Primary hyperparathyroidism;
• Vitamin D deficiency;
• Renal tubular acidosis;
• Use of diuretics.

Concentration of phosphorus in urine decreases:

• Hypoparathyroidism;
• Pseudohypoparathyroidism;
• Vitamin D poisoning.

A diet rich in potassium reduces the excretion of phosphates by the kidneys, leading to hyperphosphatemia.

Resources

https://www.synevo.ro/shop/fosfor-urinar/
https://www.webmd.com/kidney-stones/urine-phosphate-test