Laboratory Lab results are too important to go anywhere else.

Lipoprotein Associated Phospholipase A2 Activity

PLAC Test, Lipoprotein-Associated Phospholipase A₂

Test Codes

EPIC: LAB7002, PLACA

Department

Chemistry

Specimen Collection Criteria

Collect (preferred specimen): One Gold-top SST tube.
Also acceptable: One plain Red-top tube.

Physician Office/Draw Specimen Preparation

Let specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Refrigerate (2-8°C or 36-46°F) the centrifuged collection tube within four hours of collection. (Minimum: 0.5 mL)

Preparation for Courier Transport

Transport: Centrifuged collection tube, refrigerated (2-8°C or 36-46°F). (Minimum: 0.5 mL)

Rejection Criteria

Hemolyzed specimens.

Specimens not collected and processed as indicated.

In-Lab Processing

Let specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Room temperature is acceptable for a maximum of four hours.

Storage

Specimen Stability for Testing:

Centrifuged SST Tubes and Microtainers^® with Separator Gel
Room Temperature (20-26°C or 68-78.8°F): 24 hours
Refrigerated (2-8°C or 36-46°F): 14 days
Frozen (-20°C/-4°F or below): 18 months

Red-top Tubes and Microtainers^® without Separator Gel
Room Temperature (20-26°C or 68-78.8°F): 4 hours
Refrigerated (2-8°C or 36-46°F): 30 hours
Frozen (-20°C/-4°F or below): Unacceptable

Serum Specimens (Pour-Overs)
Room Temperature (20-26°C or 68-78.8°F): 24 hours
Refrigerated (2-8°C or 36-46°F): 14 days
Frozen (-20°C/-4°F or below): 18 months

Specimen Storage in Department Prior to Disposal:

Refrigerated (2-8°C or 36-46°F): 7 days

Laboratory

Royal Oak Automated Chemistry Laboratory

Performed

Friday.
Results available within five business days. 

Reference Range

Less than 225 nmol/min/mL.

Test Methodology

Enzymatic.

Interpretation

Lipoprotein-Associated Phospholipase A₂ should be used in conjunction with clinical evaluation and patient risk assessment. An elevated level may predict for an increased risk for CHD and ischemic stroke associated with atherosclerosis.

Clinical Utility

Lipoprotein-Associated Phospholipase A₂ (Lp-PLA₂) has been shown to be an independent inflammatory marker of cardiovascular risk and events. It is produced by macrophages in response to the presence of oxidized lipids and circulates primarily in association with low-density lipoprotein particles (LDL). Whereas hsCRP detects inflammation that is either part of atherosclerosis or some other systemic or localized process, Lp-PLA₂ is much more specific for vascular inflammation and appears to be a marker of unstable atherosclerotic plaques. In the West of Scotland Coronary Prevention Study (WOSCOPS) (2), there was a two-fold risk of CHD in individuals in the highest quintile compared to the lowest quintile and in the Atherosclerosis Risks in Communities Study (ARIC) (3), there was almost a two-fold risk of ischemic stroke in individuals with an increased Lp-PLA₂ level.

Reference

1. Lanman R. et al. Lipoprotein-Associated Phospholipase A₂: Review and Recommendation of a Clinical Cut-Point for Adults. Prev Cardiol 2006;9:138-143.
2. Packard CJ et al. Lipoprotein-Associated Phospholipase A₂ as an Independent Predictor of Coronary Heart Disease. West of Scotland Prevention Study Group. N Engl J Med. 2000;343:1148-1155.
3. Balantyne CM et al. Lipoprotein-Associated Phospholipase A₂, High Sensitivity C-Reactive Protein and Risk for Incident Heart Disease in Middle-Aged Men and Women in the Atherosclerosis Risk in Communities (ARIC) Study. Circulation 2004;109:837-842.

CPT Codes

83698

Contacts

Last Updated

3/29/2023