Comparison of serum and whole blood levels of cytomegalovirus and Epstein–Barr virus DNA

Abstract

The monitoring of viral DNA levels after transplantation is crucial for prevention of complications from cytomegalovirus (CMV) or Epstein-Barr virus (EBV) infection but there is no consensus as to which matrix is the most adequate. To compare serum and whole blood (WB) as specimens for measuring viral DNA, clinical samples from a 3-year period were studied, with focus on cases where serum and WB were drawn on the same day. In 1896 paired serum and WB samples, CMV DNA was detected in both specimen types in 472 samples with 0.18 log higher levels (P<0.001) in WB than in serum (median level 2.73 vs. 2.56 log copies/mL), and in only either serum or WB in 127 and 108 samples, respectively, generally at levels below 1000 copies/mL. In 664 paired samples, EBV DNA was detected in both serum and WB in 160 samples, with 1.48 log higher levels (P<0.001) in WB (median 4.2 vs. 2.4 log copies/mL), in only WB in 227 cases with a median at 3.0 log copies/mL, and only in serum in 14 samples at low levels. The correlation between serum and WB DNA levels was weaker for EBV than for CMV (R(2) 0.31 vs. 0.74). We conclude that either serum or WB may be used for monitoring CMV and EBV DNA levels, that EBV DNA is detected post transplant in >50% of WB samples and at 30 times higher levels than in serum, and that post-transplantation lymphoproliferative disorder (PTLD) may develop without further increase of EBV DNA in WB. Identification of PTLD may require EBV DNA testing in both specimen types or complementary tests.

EBV viral load detection in clinical virology

“…In studies comparing VL cellular compartments to plasma, VL was significantly higher and is detected earlier in serially monitored patients in the cellular compartment. 27 Generally, in transplant recipients, quantitative VL in WB correlates extremely well with VL measured in PBMC. 28,29 The biologic nature in which EBV exists in various compartments in transplant patients is shown in Table 1.…”

Comparative Evaluation of a Commercially Available Automated System for Extraction of Viral DNA from Whole Blood: Application to Monitoring of Epstein-Barr Virus and Cytomegalovirus Load

“…Different automated extraction methods have been previously evaluated for EBV or CMV DNA extraction from whole blood (1,3,7,9,10,(13)(14)(15)(16). To our knowledge, the present study is the first one that evaluated the performance of the NucliSENS easyMAG platform for determination of CMV and EBV loads from whole blood.…”

“…The frequent determination of EBV and CMV viral load permits the early diagnosis of infection, start of preemptive or curative therapy, and monitoring of treatment efficiency (5,17,20). By comparison to serum, plasma, or white-blood-cell fractions, whole-blood samples are now recognized as the most suitable sample for the determination of viral loads for EBV and CMV (3,4,7,9,10,12,13,18,19).Although the methods relying on silica columns are timeconsuming and need trained experimenters, these methods are considered the gold standard for the extraction of nucleic acids from whole-blood samples. Due to the large amount of genetic material in such samples, new extraction methods must be carefully evaluated, including those relying on automated devices (1, 7, 10, 14, 15).…”

Comparison of six different specimen types for Epstein-Barr viral load quantification in peripheral blood of pediatric patients after heart transplantation or after allogeneic hematopoietic stem cell transplantation

“…Several groups tried to reach standardization and compared interlaboratory PCR assays [13][14][15] or different blood compartments and reporting units. 2,[8][9][10][11][12]16 Still further examinations have to be accomplished to achieve an international standardization.…”

“…Qiagen versus triazol), the method of PCR (TaqMan PCR versus LightCycler), the assay of PCR quantification, the amplified region of EBV genome, and the standard (Namalwa cell DNA or plasmids) remain uncertain. Moreover, the use of different blood components such as whole blood (WB), plasma or serum, peripheral blood mononuclear cells (PBMC) or peripheral blood lymphocytes, different reporting units of EBV quantification, and different underlying study populations 2,[8][9][10][11][12] make it difficult to compare and evaluate results. Several groups tried to reach standardization and compared interlaboratory PCR assays [13][14][15] or different blood compartments and reporting units.…”