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Test Code
HCYS
Test Name
Homocysteine
CPT Codes
83090
Expected Turnaround Time
1 - 3 days
Clinical Utility

Can be used as a predictor of risk for ischemic stroke and myocardial infarction. Homocysteine is elevated in patients with cobalamin and/or folate deficiency and is more sensitive than serum cobalamin and serum folate concentrations in diagnosing these vitamin deficiencies.
Specimen and Container Info

Specimen Type: Plasma

Preferred Collection Container: Lavender Top (EDTA) 

Minimum Acceptable Volume: 0.4 mL
Processing and Submission Instructions

Tube must be transported to the laboratory on ice within 6 hours of drawing specimen and maintained on ice or refrigerated until processed.

Alternatively, the specimen can be processed immediately and sent frozen.

  1. Centrifuge specimen.
  2. Transfer plasma to plastic aliquot tube labeled EDTA plasma.
  3. Freeze at -20C.

Tubes with anticoagulant: To ensure accurate test results, all tubes containing an anticoagulant or preservative must be allowed to fill completely. Attempts to force more blood into the tube by exerting pressure, as in collection with a syringe, will result in damage to the red cells (hemolysis).
Patient Preparation
Fasting
Transport Instructions
  • Transport to the laboratory on ice.
  • Transport to the laboratory as a frozen aliquot.
Stability Requirements

Refrigerated

7 days, once plasma is separated from the cells.

Frozen

7 days
Methodology
Rate
Reference Intervals

HNL Lab Medicine Chemistry Reference Intervals
Performing Location
Roble Road Core Laboratory
Testing Schedule
Routine, 3 times per week
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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