Rubeola Antibodies

Synonym/acronym: Measles serology.

Common use

To assess for a rubeola infection or immunity.

Specimen

Serum (1 mL) collected in a gold-, red-, or red/gray-top tube. Place separated serum into a standard transport tube within 2 hr of collection.

Normal findings

(Method: Enzyme immunoassay)

	IgM	Interpretation	IgG	Interpretation
Negative	0.79 AU or less	No significant level of detectable antibody	0.89 index or less	No significant level of detectable antibody; indicative of nonimmunity
Indeterminate	0.8–1.2 AU	Equivocal results; retest in 10–14 d	0.9–1.0 index	Equivocal results; retest in 10–14 d
Positive	1.3 AU or greater	Antibody detected; indicative of recent immunization, current or recent infection	1.1 index or greater	Antibody detected; indicative of immunization, current or past infection

Description

Measles is caused by a single-stranded ribonucleic acid (RNA) paramyxovirus that invades the respiratory tract and lymphoreticular tissues. It is transmitted by respiratory secretions and aerosolized droplets of the secretions. The incubation period is 10 to 11 days. Symptoms initially include conjunctivitis, cough, and fever. Koplik’s spots develop 4 to 5 days later, followed by papular eruptions, body rash, and lymphadenopathy. The presence of immunoglobulin (Ig) M antibodies indicates acute infection. The presence of IgG antibodies indicates current or past infection. Susceptibility to measles is indicated by a negative reaction. Many laboratories use a qualitative assay that detects the presence of both IgM and IgG rubeola antibodies. IgM- and IgG-specific enzyme immunoassays are also available to help distinguish acute infection from immune status.

This procedure is contraindicated for

N/A

Indications

Determine resistance to or protection against measles virus
Differential diagnosis of viral infection, especially in pregnant women with a history of exposure to measles

Potential diagnosis

Positive findings in:

Measles infection

Critical findings

N/A

Interfering factors

N/A

Nursing Implications and Procedure

Pretest

Positively identify the patient using at least two unique identifiers before providing care, treatment, or services.
Patient Teaching: Inform the patient this test is to assess for measles.
Obtain a history of the patient’s complaints, including a list of known allergens, especially allergies or sensitivities to latex.
Obtain a history of exposure to measles.
Obtain a history of the patient’s immune system, symptoms, and results of previously performed laboratory tests and diagnostic and surgical procedures.
Obtain a list of the patient’s current medications, including herbs, nutritional supplements, and nutraceuticals (see Effects of Natural Products on Laboratory Values online at DavisPlus).
Review the procedure with the patient. Inform the patient that several tests may be necessary to confirm the diagnosis. Any individual positive result should be repeated in 7 to 14 days to monitor a change in detectable levels of antibody. Inform the patient that specimen collection takes approximately 5 to 10 min. Address concerns about pain and explain that there may be some discomfort during the venipuncture.
Sensitivity to social and cultural issues, as well as concern for modesty, is important in providing psychological support before, during, and after the procedure.
Note that there are no food, fluid, or medication restrictions, unless by medical direction.

Intratest

Potential complications: N/A
Avoid the use of equipment containing latex if the patient has a history of allergic reaction to latex.
Instruct the patient to cooperate fully and to follow directions. Direct the patient to breathe normally and to avoid unnecessary movement.
Observe standard precautions, and follow the general guidelines in Patient Preparation and Specimen Collection. Positively identify the patient, and label the appropriate specimen container with the corresponding patient demographics, initials of the person collecting the specimen, date, and time of collection. Perform a venipuncture.
Remove the needle and apply direct pressure with dry gauze to stop bleeding. Observe/assess venipuncture site for bleeding or hematoma formation and secure gauze with adhesive bandage.
Promptly transport the specimen to the laboratory for processing and analysis.

Post-Test

Inform the patient that a report of the results will be made available to the requesting health-care provider (HCP), who will discuss the results with the patient.
Vaccination Considerations: Record the date of the last menstrual period and determine the possibility of pregnancy prior to administration of rubeola vaccine to female rubeola-nonimmune patients. Instruct patient not to become pregnant for 1 mo after being vaccinated with the rubeola vaccine to protect any fetus from contracting the disease. The danger of contracting measles while pregnant include the possibilities of miscarriage, stillbirth, or preterm delivery. Instruct the patient on birth control methods to prevent pregnancy, if appropriate. Delay rubella vaccination in pregnancy until after childbirth, and give immediately prior to discharge from the hospital.
Reinforce information given by the patient’s HCP regarding further testing, treatment, or referral to another HCP. Instruct the patient in isolation precautions during time of communicability or contagion. Emphasize the need to return to have a convalescent blood sample taken in 7 to 14 days. Provide information regarding vaccine-preventable diseases where indicated (e.g., measles). Provide contact information, if desired, for the Centers for Disease Control and Prevention (www.cdc.gov/vaccines/vpd-vac). Answer any questions or address any concerns voiced by the patient or family.
Depending on the results of this procedure, additional testing may be performed to evaluate or monitor progression of the disease process and determine the need for a change in therapy. Evaluate test results in relation to the patient’s symptoms and other tests performed.

Related Monographs

Related tests include culture viral, rubella, and varicella.
Refer to the Immune System table at the end of the book for related tests by body system.