Venereal Disease Research Laboratory (VDRL) Test
- Laboratory Location – Central Laboratory
- CPT Code – 86593
- Synonyms – VDRL, Syphilis, Treponema pallidum
- Test Description - VDRL is a nontreponemal test that measures anti-lipid antibodies, which are formed by the patient response to lipids released from damaged cells early in infection with Treponema pallidum (the causative agent of syphilis) and lipid-like material from the treponemal cell surface. During syphilis infection, an antibody-like substance called reagin can be detected in the patient's serum and CSF. Nontreponemal tests are superior to treponemal tests for following response to therapy. The VDRL test is a reflex test that is performed when the Syphilis EIA is initially reactive or equivocal.
- Weakly Reactive
- Reactive (with quantitation)
- Specimen Type - Serum
- Specimen Container(s) - red top tubes, Marble top tubes, polypropylene vials
- Minumum accepted volume - 1 mL serum
Specimen Collection Instructions
Blood should be collected in a plastic, sterile STD Program approved collection tube. Please follow the manufacturer's instructions on clot time and centrifuge speed/time requirements.
The Syphilis Serology Lab 16 from must be filled out completely. The following information must be included on the form:
- Patient's Name
- Patient's Date of Birth
- Patient's Gender
- Patient's race/ethnicity
- Date and time of specimen collection
- Test requested
- Type of specimen collected
- Submitter's name and address
Storage and Transport Instructions
Speciments should be shipped refrigerated (2-8ºC). Specimens can be stored for up to 5 days at 2-8ºC. For longer storage, specimens must be frozen at -20ºC or colder. Frozen specimens must be shipped on dry ice and received at a temperature of -20ºC or colder.
Causes for Rejection
- Hemolyzed, lipemic, or icteric specimnes must be rejected.
- Improper labeling
- expired collection tubes
- unspun samples
- tubes that contain less than 90% of the total drawing capacity (QNS)
- Specimen age greater than 5 days if specimen has not been frozen at -20ºC or colder
- Improper storage or improper transport temperature requirements are also reasons for rejection
Limitations for the Procedure
Nontreponemal tests are not entirely specific for syphilis, nor do they have satisfactory sensitivity in all stages of syphilis. Biological false positive reactions can occur with nontreponemal tests in persons who abuse drugs, have diseases such as lupus, mononucleosis, malaria, leprosy, viral pneumonia, or have recently been immunized. Cross reactions may occur with other treponemal infections, such as yaws, pinta, bejel, or siti. A treponemal test should be done to confirm reactive VDRL results.
- Grossly hemolyzed, lipemic or icteric specimens
- CaptiaTM Syphilis IgG EIA package insert
- BD VDRL Antigen Package Insert
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