A Practical Review of Cytomegalovirus in Gastroenterology and Hepatology

Abstract

Human cytomegalovirus (CMV) is a ubiquitous Herpesviridae virus with a wide spectrum of pathology in humans. Host immunity is a major determinant of the clinical manifestation of CMV and can vary widely in the gastroenterology and hepatology practice setting. Immunocompetent patients generally develop a benign, self-limited mononucleosis-like syndrome whereas gastrointestinal tissue-invasive disease is more frequently seen in immunocompromised and inflammatory bowel disease patients. Additionally, liver allograft dysfunction is a significant consequence of CMV infection in liver transplant patients. While polymerase chain reaction and immunohistochemistry techniques allow for the reliable and accurate detection of CMV in the human host, the diagnostic value of different serologic, endoscopic, and histologic tests depends on a variety of factors. Similarly, latent CMV, CMV infection, and CMV disease carry different significance depending on the patient population, and the decision to initiate antiviral therapy can be complex and patient-specific. This review will focus on the pathophysiology, diagnosis, and management of CMV in patient populations relevant to the practice of gastroenterology and hepatology—liver transplant recipients, inflammatory bowel disease patients, and otherwise immunocompetent patients.

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

“…CMV mucosal infection cannot be diagnosed by endoscopic examination of the mucosa alone and viral markers should be analyzed in the clinical specimens [ 12 , 62 ]. The reported methods for detecting CMV infection are very heterogeneous and constitute a major bias in results’ interpretation.…”

“…One of the first and easy analyses is to screen UC patients with CMV serology in order to propose CMV detection only in IgG-positive ones [ 12 , 156 ]. Several other criteria have been proposed but there is currently no consensus on any of them, except the presence of ulcers on endoscopy should encourage analysis of viral markers in inflammatory tissue.…”

“…Human cytomegalovirus (CMV), also termed human betaherpesvirus 5, is an opportunistic pathogen involved in many inflammatory processes [ 10 ]. The diagnosis of CMV colitis in IBD patients is difficult due to the absence of clinical or endoscopic symptoms that differentiate CMV colitis from colitis associated with the inflammatory disease itself; it is based exclusively on the detection of histological or viral markers in the intestinal mucosa [ 11 , 12 ]. The aim of this review was to highlight the place of colonic CMV infection during IBD by emphasizing the relationships between CMV infection of the colonic mucosa and inflammatory flare-up of UC, the virus and the inflammation interacting with each other, which results in perpetuating and worsening colonic lesions.…”

Tocilizumab-induced Cytomegalovirus Colitis in a Patient with COVID-19

“…However, colon involvement is the most common, comprising up to 94% of cases. [8][9][10] For viral reactivation in the immunocompetent, critical illness is a major predisposing factor for developing TI-CMV disease. 11 Endoscopic findings of CMV colitis, like ulcers and inflammation, are similar to UC exacerbation.…”

Challenges and Clinical Implications of the Diagnosis of Cytomegalovirus Lung Infection in Children

“…In such cases, a mononucleosis-like picture is seen with a variable degree of constitutional and organ-specific manifestations. In the general population, more severe tissue-invasive disease is almost always limited to patients with critical illness or comorbidities conferring relative immunosuppression [4]. The diagnosis of a lung CMV infection requires a combination of respiratory symptoms along with compatible radiologic findings and detection of the virus [5].…”