High incidence of Epstein Barr virus infection in childhood acute lymphocytic leukemia: a preliminary study

Epstein Barr virus (EBV) has a unique association with several human malignancies, especially lymphoproliferative disorders, mainly lymphomas in adults. There is paucity of data pertaining to EBV association with various cancers in India .

The study aims to investigate the association of EBV in childhood leukemia.

Patients attending pediatric oncology services of the referral center have been included in the study. Twenty-five consecutive pediatric patients with acute lymphocytic lukemia (ALL) were subjected to EBV studies employing sensitive polymerase chain reaction followed by hybridization for presence of Bam H1-W region of EBV genome and detection of anti Z EBV replication activator (ZEBRA) antibodies using Western blot. Positive control included a case of Burkitt's lymphoma and infectious mononucleosis each. Raji cells were used as positive control with each test.

The PCR for EBV was positive in 8/25 patients of ALL. Western blot test using anti ZEBRA antibodies was positive in 5/25(20%) cases of ALL. Considering PCR as the gold standard, 32% of the children with ALL had evidence of active EBV replication. The positive controls were consistently positive. None of the 30 healthy laboratory controls, 22 age matched disease controls, 12 cases of AML and 15 cases of multiple myeloma were positive either by PCR or Western blots assays (P < 0. 01). There was no statistically significant correlation between duration of therapy and EBV positivity (P > 0.05).

These studies indicate that a significant number of patients with ALL show evidence of active EBV replication.