Establishment of real-time polymerase chain reaction-based assay for quantitation of Epstein-Barr virus DNA in healthy donors and in patients with EBV associated lymphoma.

Epstein-Barr virus (EBV) is associated with several malignancies including nasopharyngeal carcinoma and lymphoma in immunocompromised patients. Quantitative monitoring of EBV DNA in these patients has recently become essential for management of the disease. In the present study the authors developed a rapid and reliable real-time PCR to quantify the EBV DNA in peripheral blood mononuclear cell (PBMC) using hybridization probe technique. The real-time primers and probes in this real-time PCR system were designed based on EBNA-1 sequence. The newly-established real-time PCR demonstrated its high sensitivity (as few as 10 copies of EBV could be detected) and specificity. The intra- and inter-assay variations of the assay were shown to be within a 0.5-log10-difference range. A total of 2 EBV-seronegative, 14 EBV-seropositive healthy donors and 4 patients with PCNSL were enrolled into the study. Our results revealed the median of EBV-DNA in lymphoma patients (7886 copies/10(6) PBMC or 15,150 copies /microg DNA) was higher than that of healthy donors (<10 copies/l0(6) PBMC or <10 copies/microg DNA) with statistic significance (P < 0.01). Assessment of this assay in larger number of donors and patients will provide clinical cut-off values which are essential for monitoring and diagnosis of EBV-associated diseases.

Dengue infection: a global concern.

Dengue infection, one of the most important mosquito-borne viral diseases of humans, is now a significant problem in several tropical countries. The disease, caused by the four dengue virus serotypes, ranges from asymptomatic infection, undifferentiated fever, dengue fever (DF) to severe dengue hemorrhagic fever (DHF) with or without shock. DHF is characterized by fever, bleeding diathesis and a tendency to develop a potentially fatal shock syndrome. Hematological findings include vasculopathy, coagulopathy and thrombocytopenia as the most constant findings. During the last twenty-five years, there have been increasing reports of dengue infection with unusual manifestations, mainly with cerebral and hepatic symptoms. Laboratory diagnosis includes virus isolation, serology and detection of dengue ribonucleic acid. Successful treatment, which is mainly supportive, depends on early recognition of the disease and careful monitoring for shock. Prevention depends on control of the mosquito vector. More efforts must be made to understand the pathogenesis of DHF in order to develop a safe and effective dengue vaccine.