Test Directory

This test is used for measurement of Intact N-Terminal Propeptide of Type 1 Procollagen (PINP) levels in serum.

Specimen Type: Serum

Collection Container: Gold Top, Serum Separator

Alternate Collection Container: Red Top, Plain

Desired Specimen Volume: 0.5 mL

1. Collect specimen in gold top, serum separator tube via venipuncture.

1. Separate serum from cells within 45 minutes of collection.
2. Transfer 0.5 mL of serum to a clear aliquot tube (screw cap).

This test may exhibit interference when sample is collected from a person who is consuming a supplement with a high dose of biotin (also termed as vitamin B7 or B8, vitamin H, or coenzyme R). It is recommended to ask all patients who may be indicated for this test about biotin supplementation. Patients should be cautioned to stop biotin consumption at least 72 hours prior to the collection of a sample.

Transport to the laboratory refrigerated. 

• Nonserum sample received

See patient report.

When evaluating subsequent samples, collect the samples at the same time of the day, as there is a diurnal variation of P1NP with the values being higher at night.

The measurement of P1NP has limited specificity as it is reflective of the rate of bone turnover in general.

Type I collagen is synthesized by fibroblasts and therefore can be found in loose connective tissues together with other collagen types. However, since bone is the major collagenous organ and also metabolically active throughout life, the majority of the circulating P1NP is of osteoblast origin.

PINP is metabolized in the liver. Severe liver disease may affect clearance from the circulation and give rise to elevated serum P1NP levels.

As with most assays utilizing secondary antibodies, samples containing antibodies (such as heterophilic antibodies) that react with rabbit/goat IgG may cause erroneous results.

• Intact N-Terminal Propeptide of Type 1 Procollagen
• PINP