Low-density Lipoprotein Cholesterol CPT: 83721


Direct LDL

Direct LDLC

LDL Cholesterol, Direct

LDLC, Direct

Expected Turnaround Time

Within 1 day

Specimen Requirements


Serum (preferred) or plasma.


0.5 mL

Minimum Volume

0.4 mL


Red-top tube, gel-barrier tube, lavender-top (EDTA) tube, or green-top (heparin) tube.


Separate serum or plasma from cells within 45 minutes of collection.

Storage Instructions

Room temperature.

Stability Requirements

Temperature Period
Room Temperature 14 days
Refrigerated 14 days
Frozen 14 days
Freeze/thaw/ cycles Stable x 3

Patient Information

To determine your risk of developing heart disease; to monitor effectiveness of lipid-lowering therapy.

Screening: as part of a health exam with a lipid profile; every four to six years in adults with no risk factors for heart disease; youth should be tested at least once between the ages of 9 and 11 and once again between the ages of 17 and 21

Monitoring: may be done more frequently and at regular intervals when risk factors for heart disease are present, when prior results showed high risk levels, and/or when undergoing treatment for unhealthy lipid levels.

A blood sample drawn from a vein in your arm or from a fingerstick.

Laboratory tests for LDL-C typically require a 9 to 12-hour fast; only water is permitted. Your healthcare practitioner may decide that you may be tested without fasting. Follow any instructions you are given and tell the person drawing your blood whether or not you have fasted. For youths without risk factors, testing may be done without fasting.