Understanding Viral Load Assays for Cytomegalovirus and Epstein-Barr Virus
When to Treat EBV?

March 2010
Transplant patients are most at risk for EBV-associated PTLD within the first few months after transplant, although PTLD can also occur months or years following transplantation. Many different specimen types have been evaluated for use in quantitative EBV assays, including whole blood, plasma, and various cell fractions.
The most commonly used specimen is whole blood.
Quantitative EBV assays are sensitive, but not entirely specific for PTLD disease. That is to say that most patients who develop PTLD show increasing or high levels of EBV virus before symptom onset, though some patients with a high level of virus may remain asymptomatic. A negative result by a PCR assay for EBV has a high negative predictive value for PTLD, meaning that the short-term risk for PTLD is very low.
In the literature, proposed decision points for treatment are reported anywhere from 1000 to 50,000 (3 log to 4.7 log) copies/mL. Like CMV, factors that contribute to this broad range of numbers include patient populations, patient therapies, and laboratory detection methods.
When to Treat EBV? |
Jump to section:
- Introduction
- Cytomegalovirus and Epstein-Barr Virus Background
- Patients and Immunosuppression
- CMV in Transplant Patients
- When to Treat CMV?
- CMV Treatment Strategies
- EBV and Posttransplantation Lymphoproliferative Disorder
- When to Treat EBV?
- Treatment for EBV Infection or PTLD
- The Balancing Act of Transplant Immunology
- The Balancing Act of Transplant Immunology: Less immunosuppression
- The Balancing Act of Transplant Immunology: More immunosuppression
- The Balancing Act of Transplant Immunology
- Crucial Questions
- Viral Load Assays
- Viral Load Assays, cont.
- Variability
- Ideal Standards
- Comparing Results
- Logarithmic (log) Processes
- Advantages of Logarithmic (log) Numbers
- Integer, Scientific Notation, Logarithm
- Log vs Fold
- Disadvantages of Log
- Remember These?
- System Precision/Imprecision
- What is Significant Change?
- Reality Check
- Literature is Helpful But...
- Interpreting Viral Loads
- Review
- References
- Questions?


