Comparison of Epstein-Barr virus copy number in white blood cells of chronic lymphocytic leukemia patients with laboratory prognostic biomarker.

BACKGROUND AND OBJECTIVE

The DNA load of EBV may play a part in CLL pathogenesis and prognosis. The objective of this cross-sectional study was to examine the prognostic value of EBV viral load in CLL patients in comparison with other common laboratory prognostic factors.

MATERIALS AND METHODS

Whole blood and sera from forty untreated CLL patients were collected. Next, DNA was extracted from total white blood cells (WBC), and TaqMan real-time PCR was performed to determine the EBV-DNA load by amplifying a specific fragment in the BNRF1 gene. In addition, parameters such as complete blood counts (CBC) and lactate dehydrogenase (LDH) were determined using an automated clinical laboratory analyzer.

RESULTS

Twenty-one patients (52.5%) were positive for EBV by real-time PCR analysis (ranged 20 to 30000 copies/µL). The difference in LDH mean levels between EBV positive and negative patients was marginally significant (P = 0.05). Furthermore, platelet (PLT) count (P = 0.03) and CD5/CD19 count (P = 0.04), between EBV positive and negative subgroups, were substantially different. In addition, individuals with a severe form of illness, as defined by an increase in LDH, a decrease in PLT, and an 11q deletion, had considerably higher EBV-DNA copy numbers (the ranges of viral loads were 9966.66 ± 20033 in the severe form vs. 137.13 ± 245.41 in the mild form).

CONCLUSION

The EBV-DNA load could be used as a prognostic factor in the initial examination of CLL patients to better characterize the disease outcome and prognosis.