Kopylov U et al. – Negative history of Varicella zoster virus (VZV) exposure is a poor predictor of seronegativity. History–positive patients may still be seronegative and exposed to VZV infection. The authors suggest serological testing of all IBD patients with subsequent immunisation of the seronegative patients before initiation of immunosuppressive therapy.Methods
- History of VZV–related illness was accessed by epidemiological questionnaire, and serological testing for VZV–IgG was performed.
- Serum anti–TNF medications levels were measured when applicable.
- One hundred twenty one IBD (86% Crohn's disease, mean age 37 ± 12.8) patients were included in the study.
- Immunomodulator therapy was received by 87% (anti–TNFs– 71%) of the patients.
- Previous exposure to VZV was reported by 104 patients, and 97/104 (93%) were VZV–IgG seropositive.
- Seventeen patients, all seropositive, reported negative exposure history.
- The calculated positive and negative predictive values for the reported history of VZV exposure were 93% and 0% respectively.