IgA, albumin, eosinopenia as early warning indicators for cytomegalovirus infection in patients with acute ulcerative colitis

Background Cytomegalovirus (CMV) infection can significantly complicate and worsen the condition of acute severe ulcerative colitis (UC) patients. We aimed to explore the predictive risk factors to prevent and identify CMV infection at an early stage in acute UC patients. Methods A total of 115 moderate-to-severe active UC patients from 17 hospitals throughout China were enrolled. Active CMV infection was diagnosed by one of the following: CMV pp65 antigens, CMV IgM antibodies or CMV DNA. We identified the independent risk factors by multivariate analyses. A total of of had Compared to the the CMV-infected patients had a tendency to be male and to exhibit abdominal pain; fever; oral ulcers; eosinopenia; low albumin, immunoglobulin (Ig)A, IgM, and IgG levels; increased high-sensitivity C-reactive protein (hsCRP) levels; hyponatremia; pancolonic lesions; initial onset type; severe activity; and and (P In further the (OR and were independent CMV effect patients with active presentations of pain, fever, and oral ulcers CMV perforation, bleeding, megacolon between the infection and noninfection groups


Abstract Background
Cytomegalovirus (CMV) infection can significantly complicate and worsen the condition of acute severe ulcerative colitis (UC) patients. We aimed to explore the predictive risk factors to prevent and identify CMV infection at an early stage in acute UC patients.

Methods
A total of 115 moderate-to-severe active UC patients from 17 hospitals throughout China were enrolled. Active CMV infection was diagnosed by one of the following: CMV pp65 antigens, CMV IgM antibodies or CMV DNA. We identified the independent risk factors by multivariate analyses.

Results
A total of 64 of 115 active UC patients had active CMV infection. Compared to the non-CMV-infected patients, the CMV-infected patients had a tendency to be male and to exhibit abdominal pain; fever; oral ulcers; eosinopenia; low albumin, immunoglobulin (Ig)A, IgM, and IgG levels; increased highsensitivity C-reactive protein (hsCRP) levels; hyponatremia; pancolonic lesions; initial onset type; severe activity; and glucocorticoid (high-dose) and immunosuppressive agent use (P < 0.05). In further multivariate analyses, the use of high-dose glucocorticoids (OR 13.55, 95% CI 2.49-73.61, P < 0.01) and immunosuppressive agents (OR 11.23, 95% CI 1.

Instruction
Ulcerative colitis (UC), a type of nonspecific inflammation of the colon, is characterized by a chronic disease course and delayed healing. The morbidity and colectomy rates of UC patients have significantly decreased with the development and application of therapeutic drugs such as glucocorticoids and immunosuppressive as well as biological agents. However, the use of these therapeutic drugs alone or in combination may increase the risk of opportunistic infections. In particular, it has been shown that cytomegalovirus (CMV) infection can complicate the condition or even increase the death rate of UC patients 1 . CMV, belonging to the herpesviridae family, remains latent after the initial infection and persists throughout the lifetime of the host. Indeed, patients with inflammatory bowel disease (IBD) are often immunosuppressed and severely malnourished, which may lead to a significantly increased risk of CMV reactivation 2 . Twenty-one to thirty-four percent of acute and severe UC patients are reportedly CMV-positive, and the active CMV infection rate among those who receive urgent colectomy for UC is 10-33.3% 3-7 .
One study 8 showed that female gender, pancolic inflammatory disease and active inflammation upon histological examination were independent risk factors for CMV reactivation. However, few studies have focused on blood markers for predicting the risk of CMV infection in IBD patients. Such markers will be helpful for clinicians to monitor and improve the disease prognosis as well as to initiate early intervention strategies for preventing infection. The goal of this study was to fully understand CMV infection in Chinese patients with active UC and to identify the risk factors for CMV infection in IBD patients with different demographic characteristics. Peripheral blood CMV detection: The diagnostic standard for active CMV infection was a positive result using one of the following methods: HCMV pp65 antigen (CMV pp65), CMV IgM, and CMV DNA quantitative polymerase chain reaction (qPCR) detection. HCMV pp65 antigen detection was performed using immunofluorescence staining (HCMV Brite kit, IQ, the Netherlands). Detection of peripheral blood IgM antibodies was achieved using an enzyme-linked immunosorbent assay (ELISA) (Captia Cytomegalovirus IgM, Trinity Biotech Plc, Ireland). Quantitation of HCMV DNA was based on real-time qPCR (an HCMV nucleic acid quantitative assay kit, DAAN Gene Co., Ltd. of Sun Yat-sen University, China).

Steroid and immunosuppressive agents
The definitions of steroid and immunosuppressive agent application are described below 12 . The large steroid dose was defined as oral prednisone at ≥ 40 mg per day (qd). The moderate dose was defined as oral prednisone at ≥ 20 mg but < 40 mg qd for at least two months. The small dose was defined as oral prednisone at < 20 mg qd or oral prednisone at ≥ 20 mg qd for less than two months. The application of immunosuppressive agents was defined as the use of azathioprine, cyclosporine, or thalidomide in the past month.

Statistical methods
The clinical symptoms, Montreal classification, complications, and laboratory indicators of confirmed UC patients with or without CMV infection were retrospectively compared and analyzed. Statistical analyses were performed using SPSS 19.0 software for univariate and multivariate analyses. In univariate analyses, categorical variables were analyzed using the chi-square or Fisher's exact test.
Continuous variables following a normal distribution are presented as the mean (SD) and were analyzed by t test; otherwise, they are presented as median and interquartile ranges and were analyzed by the Mann-Whitney U test. Indicators at P < 0.05 were included in binary logistic regression for multivariate analyses. P < 0.05 indicated statistical significance.

Baseline characteristics
Of 115 patients with confirmed active UC, 64 had active CMV infection. In the active CMV infection group, the male/female ratio was 41:23, and the mean age was 47.63 ± 13.71 years. For the non-CMV infection group, the male/female ratio was 21:30, with a mean age of 44.69 ± 15.28 years. Between the two groups, the male/female ratio was significantly different: more males were in the CMV infection group, while more females were in the non-CMV infection group (P < 0.05). Conversely, age at disease onset and current admission did not differ significantly between these two groups (43.91 ± 13.17 vs. 38.78 ± 14.57; 47.63 ± 13.71 vs. 44.69 ± 15.28). The two groups did not present significant differences in the history of diabetes mellitus, appendectomy, smoking, or drinking or in the familiar history of IBD. The specific data are summarized in Table 1. Comparison and analyses of clinical manifestations, complications, and laboratory tests between the active UC with and without active CMV infection groups As shown in Table 2, the incidence rates of abdominal pain (78.1% vs. 60.8%, P = 0.043) and fever (56.3% vs. 29.4%, P = 0.005) in patients with active CMV infection were higher than those in the noninfection group. Regarding parenteral presentations, the incidence of oral ulcers in the infection group was higher than that in the noninfection group (21.9% vs. 2.0%, P = 0.002). Complications between the two groups were not significantly different.  Table 3.

Comparison and analyses of disease patterns and drug administration conditions
Compared with the non-CMV group, the active CMV infection group exhibited significantly more cases of E3 lesions, initial onset type, and severe disease. The number of patients who used immunosuppressive agents or a large dose of steroids was significantly higher in the active CMV infection group than in the non-CMV infection group.
However, the two groups did not present significant differences in the use of biological agents; history of diabetes mellitus, appendectomy, smoking, or drinking; and familiar history of IBD. These results are compiled in Table 4.

Multivariate analyses of independent risk factors for the development of active CMV infection in UC patients
As shown in Table 5   CMV infection, whereas no significant differences were observed in hematochezia and diarrhea incidence between the two groups. One possible reason for this result is that diarrhea and hematochezia are the major clinical manifestations for patients with active UC; therefore, significant differences between the two groups would be difficult to demonstrate.
With regard to complications, this study did not find significant differences in the proportions of complications between the CMV infection and noninfection groups. A recent study 14 reported that patients with CMV infection have a worse prognosis and are more prone to complications and increased colectomy rates than noninfected individuals. However, other studies did not support these results, possibly due to different inclusion criteria; for example, some studies enrolled patients with CMV infection, while others enrolled patients with CMV colitis. In addition, the results of this study indicated that patients with extensive colonic UC and severe UC are prone to CMV infection, as CMV exhibits a tendency toward inflammation and can easily infect growing cells in granulation tissues.
Moreover, extensive UC is characterized by a wide range of ulcers and more severe inflammation, Unfortunately, Ig was not included in the multivariate analysis due to missing data. Further expanding the sample size may help to obtain meaningful results.
Our study found increased rates of CMV infection in patients who received glucocorticoids and immunosuppressive agents. These results are similar to those of the majority of studies 22, 23 .
Similar to the results of another study 24 , we did not find an increased risk of CMV infection due to the use of tumor necrosis factor (TNF) inhibitors because TNF inhibitors suppress TNF, an important cytokine that promotes CMV reactivation. The limitation of this study is that due to its case-control nature, whether the indicators are the causes or results of CMV infection cannot be determined. Therefore, to confirm these risk and protective factors, cohort studies will be required for further investigation.
In summary, CMV infection may occur at the active stage of UC due to changes in the immune status