VDRL Test (Venereal Disease Research Laboratory Test)

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Category: Immune response.
Subcategory: Syphilis tests.
Material studied: Blood.
Estimated cost of test: $6.00.
Patient time for test: 5-10 minutes.
Reliability of test results: Reliability, good; specificity, fair.
Available as home self-test? No.

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BEFORE THE TEST

Purpose of test:

• Screens for syphilis in its primary and secondary stages.
• Confirms primary or secondary syphilis in the presence of infected lesions or sores.
• Monitors response to antibiotic treatment.

Where is test performed?

• Commercial laboratory, hospital, doctor's office.

Who performs test?

• Lab technician, nurse, doctor.

Risks and precautions:

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy.

Patient preparation:

• Activity - No changes necessary.
• Diet - Do not drink alcohol for 24 hours before the test.
• Medicines - No changes necessary.
• Disrobing - None required. Roll up sleeve only.

THE TEST

Sensory factors:

• Touching - You will feel mild discomfort when the needle is inserted into the vein or when the lancet pricks a finger, heel or ear lobe.
• Seeing - You will see the technician, nurse or doctor, the basket or tray to hold the equipment, the needles, syringes, collecting tubes and bandages.
• Feeling - Some degree of apprehension or fear is normal and should be expected. Discomfort disappears when the test is finished.
• Other senses (taste, smell, hearing) - Not affected.

Equipment used:

• Needles, syringes and heparinized collecting tubes. Sterile, disposable equipment prevents contamination or spread of infection. There is no risk of becoming infected with the hepatitis virus, AIDS virus or any other infecting germ.

Description of test:

• Technician, doctor or nurse applies a tourniquet or blood-pressure cuff to the upper arm if blood is collected from a vein.
• Skin over the vein to be stuck is cleaned with alcohol or other antiseptic on a piece of cotton.
• When blood is drawn from a vein, the operator feels the vein to be used then punctures both the skin and vein in one quick stroke. The needle used is a sterile, disposable needle attached to a sterile, disposable syringe.
• Operator withdraws the needle and transfers sample from the collecting syringe into sterile tubes (identified with your name) before sending samples to the laboratory for analysis. Tubes are treated with an anti-coagulant chemical to prevent clotting.
• If blood is collected from a finger, heel or ear lobe, skin over the selected site is cleaned with an antiseptic. The operator quickly pierces the skin to a shallow depth, using a sterile, disposable metal lancet. The drop or two of blood produced is collected into a capillary pipette.

AFTER THE TEST

Immediate post-test care:

• Apply pressure to the puncture site with cotton provided by the laboratory.
• If a vein has been punctured, raise your entire arm over your head while applying pressure.
• Some discoloration, soreness or swelling may develop at the venepuncture site. This responds well to moist, warm compresses applied every 2 to 4 hours.

Activity after test:

• If test result is borderline, you need follow-up testing. Borderline test results don't automatically mean you are free of the disease.
• If the test shows you have syphilis, you require antibiotic therapy.
• Contact any sexual partners so they can be treated.
• If you are uninfected and the test is positive, be aware that many uninfected people show false-positive results. You may need further tests to rule out syphilis.
• You will be contacted by public-health authorities because this is a reportable disease.

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

TEST RESULTS

Test values:

• Test results are determined by flocculation techniques.

Normal values:

• Blood is non-reactive to the test procedure accomplished in the laboratory.

What ABNORMAL may indicate:

• Result reported as REACTIVE. This means a positive test for syphilis in 50% of patients with primary syphilis and almost 100% of all patients with secondary syphilis.

Taking these drugs may affect test results:

• None expected.

Other factors that may affect test results:

• A faulty immune system.
• Infectious mononucleosis.
• Malaria.
• Leprosy.
• Hepatitis.
• Systemic lupus erythematosus.
• Rheumatoid arthritis.
• Pinta (a tropical disease).
• Yaws (a tropical disease).
• Alcohol.

From the Complete Guide to Medical Tests by H. Winter Griffith, M.D. © 1988 by Fisher Books; electronic rights by Medical Data Exchange.