The etiology of
inflammatory bowel disease (IBD) is not clear and cytomegalovirus (CMV)
infection is often associated with IBD patients. The etiologic link between IBD and CMV
infection needs to be studied. The objective of the present study is to investigate the prevalence and risk factors of CMV in a cohort of IBD patients from Central China.
METHODS: Two hundred and twenty six IBD patients (189
ulcerative colitis (UC) and 37 patients with
Crohn's disease (CD)), and 290 age and sex matched healthy controls were recruited. CMV
DNA was detected by nested PCR, while serum anti-CMV
IgG and anti-CMV
IgM was determined by ELISAs. Colonoscopy/enteroscopy with biopsy of diseased tissues and subsequent H&E
stain were then conducted in IBD patients with positive anti-CMV
IgM. Finally, we analyzed the prevalence and clinical risk factors of CMV
infection in IBD patients.
RESULTS: The prevalence of CMV
DNA and anti-CMV
IgG positive rate in IBD patients were 84.07% and 76.11%, respectively, higher than those in healthy controls (59.66% and 50.69%, respectively, P < 0.05), However, anti-CMV
IgM positive rate was no different with healthy controls (1.77% vs 0.34%, P = 0.235). In univariate analysis of risk factors, the recent use of
corticosteroid was associated with increase of CMV
DNA and
IgM positive rate in UC (P = 0.035 and P = 0.015, respectively),
aminosalicylic acid drug therapy was correlated with positivity of CMV
DNA and
IgG in UC and CMV
DNA in CD (P = 0.041, P < 0.001 and P = 0.014, respectively), the treatment of immunosuppresent was correlated with CMV
IgM (P < 0.001). Furthermore, patients with severe UC were significantly associated with CMV
DNA and
IgM (P = 0.048 and P = 0.031, respectively).
Malnutrition (
albumin < 35 G/L) was also found to be related with CMV recent
infection (P = 0.031). In multivariate analysis of risk factors in UC, pancolitis was significantly associated with CMV
DNA positivity (P = 0.001). Severe UC and pancolitis seemed to be related with
IgG positivity. For CD, there was just single factor associated with CMV positive in each group, multivariate analysis was unnecessary.
CONCLUSIONS: CMV positive rate in IBD patients was significantly higher, than in healthy controls. The use of
aminosalicylic acid,
corticosteroid,
immunosuppressants, pancolitis and severe IBD patients seemed to be more susceptible to CMV
infection in univariate analysis of risk factors. However, no risk factor was found to be significantly correlated with CMV
infection in multivariate analysis of risk factors.