Combined Infection of Human Herpes Viruses: A Risk Factor for Subsequent Colectomy in Ulcerative Colitis

From Viral Infection to Autoimmune Reaction: Exploring the Link between Human Herpesvirus 6 and Autoimmune Diseases

The complexity of autoimmunity initiation has been the subject of many studies. Both genetic and environmental factors are essential in autoimmunity development. Among others, environmental factors include infectious agents. HHV-6 is a ubiquitous human pathogen with a high global prevalence. It has several properties suggestive of its contribution to autoimmunity development. HHV-6 has a broad cell tropism, the ability to establish latency with subsequent reactivation and persistence, and a range of immunomodulation capabilities. Studies have implicated HHV-6 in a plethora of autoimmune diseases-endocrine, neurological, connective tissue, and others-with some studies even proposing possible autoimmunity induction mechanisms. HHV-6 can be frequently found in autoimmunity-affected tissues and lesions; it has been found to infect autoimmune-pathology-relevant cells and influence immune responses and signaling. This review highlights some of the most well-known autoimmune conditions to which HHV-6 has been linked, like multiple sclerosis and autoimmune thyroiditis, and summarizes the data on HHV-6 involvement in autoimmunity development.

Relationship between human herpesvirus 6 infection and inflammatory bowel disease using novel biomarker

Objective

Inflammatory bowel disease (IBD) is closely related to stress and fatigue. Human herpesvirus 6B (HHV-6B) is reactivated by stress and fatigue and is associated with IBD. This study aimed to clarify the relationship between IBD and HHV-6B.

Methods

Antibody titers to SITH-1, a protein specific to HHV-6B latent infection, were measured in 163 patients with IBD (107 with ulcerative colitis [UC] and 56 with Crohn's disease [CD]); clinical and endoscopic scores and depression scores of UC and CD were analyzed to examine the relationship between SITH-1 and IBD. The SITH-1 cut-off value was set as 1.96, according to known reports.

Results

In patients with UC, C-reactive protein (CRP) level was significantly higher (1.5 vs 0.6 mg/L, P = 0.006) and disease exacerbation within 6 months after entry was significantly more common in the SITH-1 (+) group (20% vs 0%, P < 0.001). In the subanalysis comparing with and without UC exacerbation, the optimal cut-off value for SITH-1 to detect UC exacerbation was 3.44 (area under the curve: 0.81; 95% confidence interval: 0.72-0.90). CRP levels, SITH-1 levels, and disease activity scores by the clinical or endoscopic index were significantly higher in the exacerbation group than in the non-exacerbation group (2.6 vs 0.9 mg/L, P = 0.03; 4.90 vs 1.71, P < 0.001; 4 vs 3, P = 0.03; 5 vs 3, P = 0.02; respectively).

Conclusion

Patients with UC with high titers of SITH-1 have high disease activity and frequent disease exacerbation. SITH-1 can be associated with UC disease activity.

Phage-display immunoprecipitation sequencing of the antibody epitope repertoire in inflammatory bowel disease reveals distinct antibody signatures

Inflammatory bowel diseases (IBDs), e.g., Crohn's disease (CD) and ulcerative colitis (UC), are chronic immune-mediated inflammatory diseases. A comprehensive overview of an IBD-specific antibody epitope repertoire is, however, lacking. Using high-throughput phage-display immunoprecipitation sequencing (PhIP-Seq), we identified antibodies against 344,000 antimicrobial, immune, and food antigens in 497 individuals with IBD compared with 1,326 controls. IBD was characterized by 373 differentially abundant antibody responses (202 overrepresented and 171 underrepresented), with 17% shared by both IBDs, 55% unique to CD, and 28% unique to UC. Antibody reactivities against bacterial flagellins dominated in CD and were associated with ileal involvement, fibrostenotic disease, and anti-Saccharomyces cerevisiae antibody positivity, but not with fecal microbiome composition. Antibody epitope repertoires accurately discriminated CD from controls (area under the curve [AUC] = 0.89), and similar discrimination was achieved when using only ten antibodies (AUC = 0.87). Individuals with IBD thus show a distinct antibody repertoire against selected peptides, allowing clinical stratification and discovery of immunological targets.

Impact of Epstein-Barr virus infection in patients with inflammatory bowel disease

A high prevalence of Epstein-Barr virus (EBV) infection in patients with inflammatory bowel disease (IBD) has been reported in many case reports and studies; thus, the association between EBV and IBD has gained increasing attention. Patients with IBD are at an increased risk of opportunistic EBV infection owing to the common use of immunomodulators. EBV infection in IBD patients can cause various complications, including superimposed viral colitis, which is associated with chronicity, exacerbation, and poor prognosis of refractory IBD, and can induce progression to lymphoproliferative disorders, such as EBV-positive mucocutaneous ulcer (EBVMCU), lymphomatoid granulomatosis (LYG), hemophagocytic lymphohistiocytosis (HLH) and diffuse large B-cell lymphoma (DLBCL). It has been suggested to screen for EBV before initiating immunosuppressive therapy and monitor the status of EBV infection in patients with IBD, especially those who are EBV-seronegative and have a risk of primary EBV infection. Clinicians should also be careful of misdiagnosing IBD and EBV-associated lymphoproliferative diseases due to similarities in both clinical symptoms and endoscopic manifestations. Withdrawal of immunosuppressants has been shown to be an effective strategy to achieve remission of disease at the time of EBV diagnosis, but antiviral therapy remains controversial. The present review aims to describe the characteristics of the complications caused by EBV infection and generalize the recent research progress on and challenges caused by EBV infection in IBD patients. The literature for writing this review was collected from 'PubMed' research engine. The keywords 'inflammatory bowel disease and Epstein-Barr virus' or 'ulcerative colitis and Epstein-Barr virus' or 'Crohn's disease and Epstein-Barr virus' were used to collect the literature and relevant papers were collected to help writing this review.

Chronic active Epstein-Barr virus enteritis: A literature review

Chronic active Epstein-Barr virus (CAEBV) enteritis is a rare disease that has not been well described. Owing to the similarities between CAEBV enteritis and inflammatory bowel diseases such as ulcerative colitis and Crohn's disease, it is easy to be misdiagnosed and mistreated in clinical practice, resulted in complications and even death in severe cases. Through a literature review, this study aimed to summarize the clinical characteristics, pathological features, examinations, and treatment strategies of CAEBV enteritis and its similarities and differences with inflammatory bowel diseases.

The Impact of Human Herpesviruses in Clinical Practice of Inflammatory Bowel Disease in the Era of COVID-19

Human herpesviruses (HHVs): herpes simplex virus (HSV) types 1 (HSV-1) and 2 (HSV-2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), HHV-6, HHV-7, and HHV-8, are known to be part of a family of DNA viruses that cause several diseases in humans. In clinical practice of inflammatory bowel disease (IBD), the complication of CMV enterocolitis, which is caused by CMV reactivation under disruption of intestinal barrier function, inflammation, or strong immunosuppressive therapy, is well known to affect the prognosis of disease. However, the relationship between other HHVs and IBD remains unclear. In the transplantation field, reactivation of other viruses, such as HHV-6, could cause colitis under immunosuppressed condition. Recent research revealed that combined infection of some HHVs could be a risk factor for colectomy in patients with ulcerative colitis. This suggests that it would be important to clarify HHV behavior in the treatment for patients with IBD, especially in those under immunosuppressive therapies. Looking at the relationship with recently emerged novel coronaviruses (SARS-CoV-2), there are reports describe that SARS-CoV-2 might induce reactivation of HSV-1, EBV, VZV (herpes zoster), and HHV-6/7. If SARS-CoV-2 infection becomes common, vigilance against HHV reactivation may become more crucial. In this review, we discuss the impact of HHVs in clinical practice of inflammatory bowel diseases, especially during the SARS-CoV-2 pandemic.

Impact of Epstein-Barr virus infection on inflammatory bowel disease (IBD) clinical outcomes

OBJECTIVE

To evaluate the role of Epstein-Barr virus (EBV) on the intestinal mucosa in the evolution of inflammatory bowel disease (IBD), to investigate the risk factors for EBV infection and the frequency of EBV-associated lymphoproliferative disorders in IBD patients.

METHODS

Intestinal biopsies of IBD patients with available EBV status determined by Epstein-Barr-encoding RNA (EBER) in situ hybridization were searched in the Pathology Database of our center. Clinical information, including phenotypic characteristics of IBD, previous treatments, diagnosis of lymphoma, and patient outcome, were reviewed for all cases.

RESULTS

56 patients with IBD (28 Crohn´s disease, 27 ulcerative colitis and one unclassified colitis) were included. EBV in intestinal mucosa was positive in 26 patients (46%), in one case associated to a lymphoproliferative syndrome. EBV positivity was associated with severe histological activity (52% vs. 17.2%; p 0.007), presence of a lymphoplasmacytic infiltrate (50% vs. 33.3%; p 0.03) and active steroid treatment (61.5% vs. 33.3%; p 0.03). Multivariate analyses only found association between EBV and lymphoplasmacytosis (p 0.001). Escalation in previous treatment was significantly more frequent in the EBER+ group (53.8% vs. 26.7%; p 0.038). No cases developed lymphoma in the follow-up.

CONCLUSIONS

EBV on the intestinal mucosa is associated with a poor outcome of IBD and the need for escalation in therapy. Lymphoplasmacytic infiltrate is associated with EBV infection. EBER+ patients used steroids more frequently compared with EBER- patients. No EBER+ patients developed a lymphoma during follow-up.

Clinical features of Epstein-Barr virus in the intestinal mucosa and blood of patients with inflammatory bowel disease

BACKGROUND

The role of Epstein-Barr virus (EBV) in inflammatory bowel disease (IBD) remains to be elucidated. The aim of this study was to investigate the presence of EBV in the blood and intestinal mucosa of patients with IBD and evaluate the association between EBV positivity and IBD.

METHODS

Patients with IBD, hospitalized between January 2015 and April 2018, were enrolled. The EBV-DNA load in blood samples from each subject was analyzed by quantitative real-time polymerase chain reaction. EBV-encoded small-RNA 1 (EBER-1) was detected by in-situ hybridization in intestinal mucosa tissue sections of patients with IBD.

RESULT

EBV-DNA was detected in 48 out of 568 patients with IBD (8.4%), and EBER-1 positivity was detected in 27 of these patients (56.3%). Refractory IBD and severe mucosal inflammation were more common in patients with detectable levels of EBER-1 than in those without; the number of EBER-1-positive cells positively correlated with mucosal inflammation (P value < 0.05). Age (≥60 years old) and use of azathioprine were risk factors for EBV infection. There was no significant difference in clinical remission rate and surgical rate between the EBER-1 positive group and EBER-1 negative group, antiviral group and the non-antiviral group, among IBD patients who tested positive for EBV-DNA.

CONCLUSION

Elderly patients with IBD, treated with azathioprine, are more susceptible to EBV positivity. Further, EBV mucosal detection correlated with the severity of mucosal damage and refractoriness, but not prognosis.

Cytomegalovirus and Inflammatory Bowel Diseases (IBD) with a Special Focus on the Link with Ulcerative Colitis (UC)

Cytomegalovirus (CMV) infects approximately 40% of adults in France and persists lifelong as a latent agent in different organs, including gut. A close relationship is observed between inflammation that favors viral expression and viral replication that exacerbates inflammation. In this context, CMV colitis may impact the prognosis of patients suffering from inflammatory bowel diseases (IBDs), and notably those with ulcerative colitis (UC). In UC, the mucosal inflammation and T helper cell (T_H) 2 cytokines, together with immunomodulatory drugs used for controlling flare-ups, favor viral reactivation within the gut, which, in turn, increases mucosal inflammation, impairs corticoid and immunosuppressor efficacy (the probability of steroid resistance is multiplied by more than 20 in the case of CMV colitis), and enhances the risk for colectomy. This review emphasizes the virological tools that are recommended for exploring CMV colitis during inflammatory bowel diseases (IBD) and underlines the interest of using ganciclovir for treating flare-ups associated to CMV colitis in UC patients.

Prospective study of blood viral load of Epstein-Barr virus, herpes virus type 6 and human parvovirus B19 in Crohn's disease: Does therapy matter?

BACKGROUND

The interplay between inflammatory bowel disease (IBD) and DNA viruses, such as Epstein-Barr (EBV), human parvovirus B19 (HPVB19) and human herpes type 6 (HHV6) is scarcely studied. The main aim of this prospective study is to screen for EBV, HSV6, and HPVB19 DNA viremia in adult patients with stable Crohn's disease (CD), correlating the results with IBD treatment.

METHODS

From July 2015 - March 2017, 100 patients were enrolled and divided in four groups of 25 participants each, according to in course treatment. Blood collections were performed every 5 months in all patients. Antibodies for EBV and HPVB19 were screened and repeated if negative. Blood EBV DNA, HPVB19 DNA, and HHV6 DNA were quantified by quantitative real-time Polymerase Chain Reaction.

RESULTS

Patients had evidence of EBV (100 %) and HPVB19 (70 %) past infection. Across the study timeline, EBV-DNA, HPVB19-DNA, and HHV6-DNA were detected in the blood of 25, 11, and 7 patients, respectively. Viremia was detected only once in 72 %, 73 %, and 86 % of the patients in the studied period, for EBV, HPVB19, and HHV6, respectively. We did not find significant differences between treatment groups, independently of the viral cut-off for the three viruses.

CONCLUSIONS

The detection of EBV, HPVB19, and HHV6 viremia, in stable CD patients, was not impacted by biological/immunosuppressant therapy. Although attractive as a non-invasive technique, this approach did not prove to be useful in stable patients. More and larger studies are needed to address the relevance of these viruses on IBD course, in stable patients and during exacerbations.

A review on co-existent Epstein-Barr virus-induced complications in inflammatory bowel disease

There have been growing reports regarding the presence of Epstein-Barr virus (EBV) in the intestine portions of patients suffering from ulcerative colitis and Crohn's disease, collectively termed as inflammatory bowel disease (IBD). Indeed, the prevalence of EBV infection increases in IBD patients due to prolonged employment of immunosuppressive drugs including azathioprine and infliximab. In turn, coinfection with EBV increases the propensity of development of lymphoproliferative disorders in the gastrointestinal tract including Hodgkin lymphoma, non-Hodgkin lymphomas, and lymphoepithelioma-like cholangiocarcinoma. Therefore, it is recommended that IBD patients on prolonged immunomodulator therapy should be monitored for the presence of primary intestinal lymphoproliferative diseases. Moreover, coinfection of EBV complicates the clinical course of IBD by increasing the severity, chronicity, inducing refractoriness and increasing relapse incidences. Therefore, it is recommended that antiviral drugs should be added in the conventional IBD therapy in the suspected cases of EBV infection. Research has also revealed that EBV-induced colitis is very similar to IBD and there are chances of misdiagnosis of IBD in the presence of EBV colitis. The proper diagnosis of EBV infection along with its timely treatment is necessary to avoid the severe complications in patients of IBD. The present review discusses the role of EBV coinfection in increasing the clinical complications of IBD patients.