Homocysteine, Total

Tube Type

Test ID		LAB93
EPIC Order		HOMOCYSTEINE
CPT Code(s)		83090
Group/Individual Test		Individual
Laboratory		Core Laboratory
Tube Station		Routine: 30
Specimen	Routine:	2 mL of blood/lavender EDTA tube, COLLECT ON ICE; See below for alternate specimen types and comments
Stability		Once separated from the cells, plasma is stable: Room temperature: 8 hours Refrigerator: 48 hours Frozen: 13 weeks
	Micro:	300 µL blood/lavender EDTA microtainer, Collect on ICE
Availability	Routine:	24 hrs/day
Turnaround Time	Routine:	2 hrs
Reference Range	Normal:	3.7 - 13.9 µmol/L
Alternate Specimen Types		2 mL green lithium heparin gel tube, Collect on Ice or 2 mL gold SST tube, Collect on Ice
Comment	Deliver to Laboratory Immediately. If Outpatient, maintain on ice during transport to laboratory. If possible, centrifuge in refrigerated centrifuge, separate and transport plasma ON ICE. SAMPLE is NOT STABLE at ROOM TEMPERATURE if left on the cells. Sample should be centrifuged within one hour or on ice. If sample is stored on ice, centrifugation and separation from the cells must occur within 8 hours.

Reviewed by J. Carr on November 25, 2025

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514