Diphtheria Antitoxoid [4865]

For Specimen Integrity during Extreme Weather see the “Lockbox Usage in Extreme Weather” document at the top of this page.

Test Code

Alias/See Also

CPT Codes

Preferred Specimen
1 mL serum

Minimum Volume
0.3 mL

Transport Container
Transport tube

Transport Temperature
Room temperature

Specimen Stability
Room temperature: 7 days
Refrigerated: 14 days
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis, gross lipemia, gross icterus

Immunoassay (IA)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule
Setup: Daily; Report available: 1-2 days

Reference Range
≥0.10 IU/mL

Interpretive Criteria
<0.10Nonprotective Antibody Level
≥0.10Protective Antibody Level

Antibody levels ≥0.10 are considered protective. After a primary series of three properly spaced diphtheria toxoid doses in adults or four doses in infants, a protective level of antitoxin (defined as ≥0.10 IU of antitoxin/mL) is reached in more than 95% of immunized persons.

Clinical Significance
Used to evaluate diphtheria immunization response. Antibody levels of ≥0.10 IU/mL are considered protective. For Pre and Post vaccination testing to assess normal immune response, please refer to test code 10680-Diphtheria Antitoxoid, Pre and Post Vaccination.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Dr
Chantilly, VA 20153

Last Updated: November 29, 2021

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.