Letter: mucosal PCR for cytomegalovirus in refractory ulcerative colitis

Abstract

SIRS, We read with great interest the article by Chaparro et al. In this paper, the authors described that predictive factors of colectomy were not identified. We would like to ask the authors about involvement of cytomegalovirus (CMV) infection in ulcerative colitis (UC) patients who required colectomy after infliximab salvage therapy. Cytomegalovirus infection is implicated in exacerbation of UC. However, virological criteria for diagnosing CMV infection in UC have not been standardised. We reported the usefulness of quantitative real-time polymerase chain reaction (PCR) using colonic specimens (mucosal PCR) for detecting CMV infection in patients with refractory UC. The European Crohn’s and Colitis Organization guidelines supported the importance of detection of CMV infection in inflamed mucosa, and recommended mucosal PCR for investigating CMV infection in UC patients refractory to immunosuppressive therapies. 4 In this regard, mucosal PCR could be suitable for evaluating CMV infection. We demonstrate the significance of mucosal PCR in the clinical outcome of UC patients treated with infliximab salvage therapy after tacrolimus. From January 2001 to March 2012, 17 patients with UC refractory to tacrolimus (mean age: 64 years; 6 men, 11 women) were treated with infliximab. Nine of 17 patients with UC were positive for CMV-DNA in colonic mucosa, while eight patients were negative. After a median follow-up of 20 months, six patients (35.3%) underwent colectomy. A significant difference in colectomy free survival was observed between UC patients testing positive for CMV-DNA in colonic mucosa and negative individuals (Figure 1; 35.7% at 17.7 months vs. 88.9% at 45.9 months; log-rank test: P < 0.05). Therefore, mucosal PCR could open a way to not only predict clinical outcome but also therapeutic strategies for patients with refractory UC.