The need for better preventative strategies for inflammatory bowel disease patients at risk of herpes zoster virus.

Background: Immunosuppressed inflammatory bowel disease (IBD) patients have an increased risk of herpes zoster virus (HZV) infection. The existing live-attenuated HZV vaccine is contraindicated in some of these patients and can only be used with caution in others.

Aims: To describe characteristics of IBD patients suffering HZV to enable implementation of risk mitigation strategies for those at highest risk.

Methods: Gastroenterologists completed a proforma for IBD patients who experienced HZV infection: IBD phenotype, details of HZV infection, immunosuppression and any change to treatment upon diagnosis of HZV.

Results: A total of 30 cases was identified: Crohn disease (CD) (n = 25) and ulcerative colitis (n = 5). In total, 80% (20/25) of the CD patients had penetrating, stricturing or perianal disease. Time from commencement of immunosuppression to HZV infection was highly variable (range: 3 months to over 10 years). A total of 90% (27/30) of patients was on at least one immunosuppressive therapy; of those, one-third was on monotherapy (9/27) and two-thirds (18/27) on dual therapy. A total of 89% (24/27) of immunosupressed patients was on a thiopurine (monotherapy; 6/27) or in combination (18/27). Complications of HZV occurred in 27% (8/30) of patients.

Conclusion: Our series is consistent with existing epidemiological analysis that identified more severe IBD and the use of multiple immunosuppressive therapies as risk factors for HZV. If the promise of an investigational subunit HZV vaccine is realised in immunocompromised patients, better protection may be possible in the future. Thiopurine medications were the most commonly used immunosuppressant in this series. Age and duration of immunosuppressive therapy do not appear to predict HZV infection.