Incidence of Cytomegalovirus Infection in Hospitalized Adult Patients With IBD Treated With a Drug Regimen Containing Mercaptopurine

Abstract

Introduction: Immunocompromised patients are known to be at increased risk of CMV infection. Patients with IBD may be at higher risk of developing CMV disease often affecting various organ systems. This can lead to life-threatening systemic illness. The increased risk for opportunistic disease is likely multifactorial and is thought to be due to malnourishment, immunosuppressive therapy and poor NK cell function. We sought to further investigate the effect of immunosuppressive therapy contributing to an increased risk of developing active CMV viremia in the hospitalized IBD population at our tertiary center. Methods: We conducted a single-center, retrospective review of 85 patients tested for CMV from October 2014 through November 2017. Inclusion criteria included adults age 18 and older with a known IBD diagnosis. CMV testing modality included DNA and/or immunoglobulin testing of plasma, CSF and tissue biopsy specimens. Home medication regimen at the time of CMV testing was also assessed to further evaluate the relationship between immunosuppressive and biologic therapy to CMV viremia. Results: Of 85 patients who were tested for CMV, 41 (48%) had a confirmed IBD diagnosis (UC or Crohn's disease). Four (9.7%) patients with IBD tested positive for CMV viremia (two had Crohn's disease and the other two had UC). The patients with CMV presented uniquely, two had hematochezia and ileocolitis/colitis, one had dyspnea and was found to have CMV pneumonia and one presented with chronic sore throat and was noted to have active CMV viremia. Ten out of 41 (24%) patients were on anti-TNF therapy (including infliximab, adalimumab and certolizumab) and only one (10%) tested positive for CMV infection in this group. Another ten (24%) patients were on a regimen containing mercaptopurine and of these, three (30%) tested positive for CMV. The patients who tested positive denied a smoking history and ranged in age from 22 to 67 years. Conclusion: Immunomodulators and biologics are widely used in the treatment of moderate to severe IBD and are associated with side effects including bone marrow suppression and infections, particularly opportunistic infections like CMV. Our data suggests that patients receiving a mercaptopurine-containing regimen have a higher risk of acquiring active CMV infection when compared to those receiving biologics alone. We plan to expand the present study using a larger patient population to further identify correlations between treatment regimen and development of CMV in the setting of IBD.