EBV Status and Thiopurine Use in Pediatric IBD

Epstein Barr virus (EBV) is a human herpes virus that infects 90% of the world's population and has been linked to the development of lymphoproliferative disorders (LPDs) and immunosuppression. Primary EBV infection in patients with IBD on thiopurines is a risk factor for LPD, including lymphoma. We aimed to describe EBV status in a pediatric population with IBD with an emphasis on those initiating thiopurines.

Electronic medical records and EBV serologies were reviewed and categorized into asymptomatic screening versus suspicion for acute infection. EBV status before therapy was described by sex, age, and therapeutic regimen. Descriptive statistics and univariate analysis were employed.

Only 150 (22%) of our 688 pediatric patients with IBD had documented EBV status regardless of age or treatment regimen. Only 17% were assessed for suspicion of acute infection and 83% for screening. Sixty-four (52%) screened patients were checked before starting any treatment and only 40% were immunoglobulin (Ig)G positive. There was no difference in mean age between the seronegative and seropositive group. The majority (63%) of thiopurine-treated patients were IgG negative before starting therapy. Eighty percent of primary EBV infections occurred on thiopurines at a mean (SD) of 2 ± 1.5 years after initiating therapy.

The majority of our pediatric patients with IBD with documented EBV status were IgG negative at thiopurine initiation. Thiopurines were also associated with primary EBV infection. EBV status may be an important determinate of whether physicians prescribe thiopurines given the risk of primary EBV infections and lymphoproliferative diseases.