Clinical Characteristics And Prognosis In Cytomegalovirus-positive Ulcerative Colitis: A Meta-analysis

Ulcerative colitis(UC)is a long-term condition that results in non-specific inflammation and ulcers of the colon and rectum.Due to the disruption of intestinal mucosal barrier function and the therapy of glucocorticoid and immunosuppressive agents in some patients,the risk of opportunistic infections in UC patients is extremely high.Cytomegalovirus(CMV)is a member of opportunistic pathogens presenting in the form of latent infection.CMV infection is more common in UC patients and it can cause the rapid disease progresses and worsen effect of conventional treatment.But risk factors,clinical significance and endoscopic features in UC patients complicated with CMV infection still remain controversial.And the impact of CMV infection on the prognosis and whether antiviral therapy can alleviate the progression are still controversial.Our study provided reference frame by analyzing the high risk factor,clinical significance,endoscopic features,disease prognosis and antiviral condition of UC patients through a meta-analysis,for further understanding the features of CMV infection and providing evidence for the diagnosis and treatment of UC patients with CMV infection.Objective: To confirm the features of CMV infection and provide evidence of the diagnosis and treatment of UC patients with CMV infection.Method: Searching of the Pubmed database,Cochrane database,Embase database,CNKI database,Wanfang database,Sino Med database and VIP database up to March 2017 were performed.Our search strategy was constructed by using a combination of the following key words:(ulcerative colitis or UC or inflammatory bowel disease or IBD or)and(cytomegalovirus or CMV).Articles published in any language were included and were screened according to the inclusion and exclusion criteria.The Rev Man5.3 software was used for analysis.Results: After searching 1497 studies,we included 23 studies,containing 21 English studies and 2 Chinese studies respectively published in 17 journals,involving 762 patients and 1218 controls.The study included 23 related literature,13 for the high risk factors,18 for the clinical significance,7 for the endoscopic features and 7 for the effect of antiviral therapy.(1)Meta-analysis for the 13 literature on the risk factors of CMV infection in UC patients showed that the risk of CMV infection in severe UC was 1.45 times higher than that in mild to moderate UC and the risk in whole colon was 1.54 times than that of patients with left colon and rectum with the pooled OR values as 1.45(1.02~2.05)and 1.54(1.05~2.27).The risk of CMV infection in middle-aged patients with UC was higher than that in young patients with the pooled OR values as 4.60(2.13~7.07).The therapy of glucocorticoid and immunosuppressive agents such as azathioprine,cyclosporine and methotrexate were high risk factors of CMV infection in UC patients,with the pooled OR values as 3.87(2.70~5.53)and 2.07(1.29~3.32),but the the duration of UC,treatment with 5-ASA/SASP and infliximab had no statistical significance in the CMV infection of UC patients,with the pooled OR values as-1.20(-2.64~0.24),0.94(0.61~1.42)and 1.50(0.65~3.44).(2)A total of 18 articles on the clinical significance of CMV infection in UC patients were analyzed.The results showed that UC patients in CMV infection group were more serious and had larger intestinal lesions,with the pooled OR values as 1.74(1.20~2.43)and 1.59(1.08~2.34).The combination of CMV infection significantly increased the risk of hormone dependence/ resistance and colectomy,with the pooled OR values as 9.13(2.97~28.02)and 1.64(1.14~2.35).(3)Meta-analysis for the 7 literature on the endoscopic features of CMV infection in UC patients showed that the characteristics of longitudinal ulcers,punched-out ulceration,cobblestone appearance under colonoscopy often indicate CMV infection except wide mucosal defect,with the pooled OR values as 2.78(1.65~4.66),4.47(2.32~8.62),3.24(1.75~6.02)and 3.06(0.94~ 9.98).(4)Meta-analysis for the 7 literature on the disease progression of antiviral therapy in UC patients with CMV infection showed that the antiviral therapy significantly improved the early clinical remission rate,but didn't affect the risk of short-term,long-term and total colectomy with the pooled OR values as 2.08(1.03~4.17),1.60(0.69~3.70),1.81(0.64~5.13)and 1.81(0.88~3.72).Conclusions: 1 Patients with severe UC,whole colon leisions and the therapy of glucocorticoid and immunosuppressive agents were the risk factors of CMV infection in UC patients while 5-ASA and infliximab therapy had no effect.The risk of CMV infection in middle-aged patients was higher than that in young patients.2 CMV infection can aggravate the progress of the disease,enlarge the range of intestinal diseases and increase the risk of hormone dependence/ resistance and colectomy in UC patients.3 The colonscopic features of longitudinal ulcers,punched-out ulceration and cobblestone appearance indicate CMV infection except wide mucosal defect.4 Antiviral therapy significantly improves the early clinical remission rate,but has no effect on the risk of short-term,long-term and total colectomy.