Epstein-Barr Virus - EBV

Dx
Monitor
Background
Lab Tests

Diagnosis

Indications for Testing

Acute persistent pharyngitis and lymphadenopathy with negative strep testing

Laboratory Testing

EBV diagnosis and testing information (CDC)
CBC with differential – elevated white blood cells with atypical lymphocytes
Rapid strep test and/or culture – negative
Positive heterophile antibody (IgM antibodies not specific for EBV) – point of care testing (eg, Monospot)
- Heterophile test is often negative in children <5 years; misses 50-70% of cases
- Antibodies develop after about day 5 of illness; do not test before 4-5 days

Diagnosis of acute disease due to EBV depends mostly on testing for an immune response to the virus

Immune response during acute infection may be significantly delayed, especially in children and immunocompromised hosts
Extensive workup appropriate in markedly febrile patient with enlarged nodes and for whom prior testing was negative
Initial antibody testing should include EBV anti-viral capsid antigen (VCA) IgM and IgG
Interpretation of serologic results (see table below)

Infection	VCA G	VCA M	EA	EBNA
No previous	-	-	-	-
Acute	+	+	±	-
Recent	+	±	±	±
Past	+	-	-	+
*Reactivation	+	±	+	+
* Antibody to the early antigen in the presence of a positive EBNA does not automatically indicate that a patient's current medical condition is caused by EBV reactivation. Healthy individuals with no symptoms can have antibodies to early antigen for years after initial EBV infection. Reactivation can occur subclinically.

If testing is negative for EBV, consider serologies for cytomegalovirus (CMV) IgM, human herpesvirus 6 (HHV6) IgM and HIV testing

PCR, ELISA, probe testing – all usually reserved for immunocompromised patients or those with EBV-related tumors

Histology

Paraffin evaluation of tissue may be used for virus identification of EBV
Immunohistochemistry – stain for EBV latent membrane protein

Differential Diagnosis

Pharyngitis
- Streptococcal disease, group A
- Cytomegalovirus
- Human immunodeficiency virus
- N. gonorrhea
- Adenovirus, rhinovirus
- Toxoplasma gondii
- Human herpesvirus 6
- Herpes simplex virus-1
- Coxsackievirus A
Lymphadenopathy

Monitoring

EBV quantitative viral load testing may be indicated in transplant patients who develop primary mononucleosis or in new transplant patients
Inability to clear viral load after primary mononucleosis may be surrogate for PTLD
Increasing titers may signal reason to decrease immunosuppressive therapy to abort PTLD

Clinical Background

Epstein-Barr virus (EBV) is the cause of a variety of disorders, including mononucleosis.

Epidemiology

Age – usually <21 years
- 50% seropositive <5 years
Transmission – salivary contact

Organism

Gamma herpesvirus that belongs to the Herpesviridae family
Like other herpes viruses, may remain dormant for years as a latent infection
- Infects B lymphocytes, which can then be reactivated

Clinical Presentation

Primary infection often manifests as infectious mononucleosis (IM)
- IM usually self-limiting and characterized by the following
  - Fever
  - Sore throat
  - Myalgias
  - Lymphadenopathy
  - Hepatosplenomegaly
Rare complications – hemolytic anemia and splenic rupture
Other serious symptoms may occur in extremes of age and among immunocompromised patients
- Thrombocytopenia
- Bulky adenopathy (cervical and axillary most common)
- Hemolytic anemia
- Hepatitis
- Meningitis
- Myocarditis
Disorders associated with EBV
- Infectious mononucleosis
- Endemic Burkitt lymphoma
  - Primarily in Africa; less common in developed countries
  - High grade B-cell lymphoma
  - >80% of nonendemic Burkitt lymphomas are EBV-negative
- Nasopharyngeal carcinoma (endemic in China)
  - Malignant nasopharyngeal tumor of the squamous epithelium
- Other cancers
  - EBV-associated Hodgkin lymphoma (mixed cellularity subtypes)
  - Tonsillar carcinoma
  - T-cell lymphomas (especially sinonasal T-cell lymphomas)
  - Thymoma
- X-linked lymphoproliferative syndrome (Duncan disease)
  - Often results in fatal, polyclonal B-cell proliferation
- Progressive lymphoproliferative diseases
  - Children with primary immunodeficiencies
  - Post-transplant lymphoproliferative disorders (PTLD)
  - Immunosuppressed or AIDS patients
- No good evidence to implicate EBV in chronic fatigue syndrome

Treatment

Treatment is supportive
- No contact sports for 6-8 weeks due to risk of splenomegaly and splenic rupture
- Steroids often used for severe symptoms

Indications for Laboratory Testing

Tests generally appear in the order most useful for common clinical situations
Click on number for test-specific information in the ARUP Laboratory Test Directory

Test Name and Number	Recommended Use	Limitations	Follow Up
CBC with Platelet Count and Automated Differential 0040003 Method: Automated Cell Count/Differential	Nonspecific testing in mononucleosis
Infectious Mononucleosis Slide Test by LA 0050385 Method: Semi-Quantitative Latex Agglutination	Initial testing to confirm infectious mononucleosis or recent EBV infection (Monospot test)	Negative Monospot test is common in children and immunocompromised adults	If test results are negative but a strong clinical suspicion exists, repeat testing in 7-14 days
Epstein-Barr Virus Antibody to Viral Capsid Antigen, IgM 0050240 Method: Semi-Quantitative Chemiluminescent Immunoassay	Evaluation of equivocal or negative Monospot test, especially in patients at risk for splenic rupture (contact sports) Discriminate EBV from other IM-like diseases (eg, CMV, toxoplasmosis)		Rule out other causes of lymphadenopathy by ordering antibody tests for toxoplasmosis and CMV Repeat testing in 10-14 days may be helpful if results are equivocal
Epstein-Barr Virus Antibody to Viral Capsid Antigen, IgG 0050235 Method: Semi-Quantitative Chemiluminescent Immunoassay	Evaluation of equivocal or negative Monospot test, especially in patients at risk for splenic rupture (contact sports)		Rule out other causes of lymphadenopathy by ordering antibody tests for toxoplasmosis and CMV Repeat testing in 10-14 days may be helpful if results are equivocal
Epstein-Barr Virus Antibody to Nuclear Antigen, IgG 0050245 Method: Semi-Quantitative Chemiluminescent Immunoassay	Confirm previous infection with EBV		Rule out other causes of lymphadenopathy by ordering antibody tests for toxoplasmosis and CMV Repeat testing in 10-14 days may be helpful if results are equivocal
Epstein-Barr Virus by PCR 0050246 Method: Qualitative Polymerase Chain Reaction	Detect EBV in cerebrospinal fluid and serum specimens Diagnose EBV-related diseases in immunocompromised patients or patients with lymphoproliferative tumors Do not use to confirm acute mononucleosis	Negative result does not rule out the presence of PCR inhibitors in patient specimen or EBV DNA in concentrations below assay detection
Epstein-Barr Virus, Quantitative PCR 0051352 Method: Quantitative Polymerase Chain Reaction	Monitor disease – usually in immunocompromised patients (plasma, serum or CSF specimens) Do not use to confirm acute mononucleosis	The limit of quantification for this DNA assay is 2.6 log copies/mL (390 copies/mL); if the assay DID NOT DETECT the virus, the test result will be reported as “<2.6 log copies/mL (<390 copies/mL)” If the assay DETECTED the presence of the virus but was not able to accurately quantify the number of copies, the test result will be reported as “Not Quantified" Inhibition may also lead to underestimation of viral quantitation
Epstein-Barr Virus, Quantitative PCR, Whole Blood 0051353 Method: Quantitative Polymerase Chain Reaction	Monitor disease – usually in immunocompromised patients (whole blood specimens) Do not use to confirm acute mononucleosis	The limit of quantification for this DNA assay is 2.6 log copies/mL (390 copies/mL); if the assay DID NOT DETECT the virus, the test result will be reported as “<2.6 log copies/mL (<390 copies/mL)” If the assay DETECTED the presence of the virus but was not able to accurately quantify the number of copies, the test result will be reported as “Not Quantified" Inhibition may also lead to underestimation of viral quantitation
Epstein-Barr Virus Antibody to Early D Antigen (EA-D), IgG 0050225 Method: Semi-Quantitative Chemiluminescent Immunoassay	Confirm chronic active mononucleosis, post-transplant lymphoproliferative disease and nasopharyngeal carcinoma This antibody test is more useful and appropriate than early antigen R for mononucleosis assessment		Rule out other causes of lymphadenopathy by ordering antibody tests for toxoplasmosis and CMV Repeat testing in 10-14 days may be helpful if results are equivocal
Epstein-Barr Virus Antibody to Viral Capsid Antigen, IgA 0051626 Method: Semi-Quantitative Enzyme-Linked Immunosorbent Assay	May be used in conjunction with Epstein-Barr Virus Antibody to Early D Antigen (EA-D), IgG to confirm chronic active mononucleosis, post-transplant lymphoproliferative disease, Burkitt lymphoma, nasopharyngeal carcinoma	IgA is variably seen; levels are not consistently elevated Results vary in acute infectious mononucleosis, chronic active mononucleosis and post-transplant lymphoproliferative disease	Rule out other causes of lymphadenopathy by ordering antibody tests for toxoplasmosis and CMV Repeat testing in 10-14 days may be helpful if results are equivocal
Epstein-Barr Virus (EBV) By in situ Hybridization, Paraffin 2002902 Method: In situ Hybridization	Virus identification of EBV
Cytomegalovirus Rapid Culture 0065004 Method: Cell Culture/Immunofluorescence	Test for CMV if EBV testing is negative
Herpesvirus 6 (HHV6) (A&B), Quantitative PCR 0060071 Method: Quantitative Polymerase Chain Reaction	Test for HHV6 if EBV testing is negative

Additional Tests Available

Click the plus sign to expand the table of additional tests.

Test Name and Number	Comments
Epstein-Barr Virus Antibody to Viral Capsid Antigen, IgG & IgA 0051627 Method: Enzyme-Linked Immunosorbent Assay/Semi-Quantitative Chemiluminescent Immunoassay
Epstein-Barr Virus Antibody Panel I 0050600 Method: Semi-Quantitative Chemiluminescent Immunoassay
Epstein-Barr Virus Antibody Panel II 0050602 Method: Semi-Quantitative Chemiluminescent Immunoassay
Heterophile Antibody by Latex Agglutination with Reflex to Titer 0050621 Method: Semi-Quantitative Latex Agglutination