Abstract
Abstract
Background Cytomegalovirus (CMV) colitis is a critical clinical condition associated with severe complications in ulcerative colitis (UC). This study aims to investigate the diagnostic value of CMV DNA in intestinal mucosa tissue and blood samples in patients with active UC.
Methods The study included 81 patients experiencing exacerbations of UC symptoms. The patients' demographics, symptoms, disease activity, endoscopic findings, and medications were obtained from the Hospital Information System. CMV DNA was analyzed with the real-time quantitative polymerase chain reaction (qPCR) method on patients' colorectal tissue samples and plasma. CMV markers were investigated with immunohistochemistry (IHC) and hematoxylin-eosin staining (H&E).
Results It was found that older age, active tissue inflammation, a previous CMV infection, and corticosteroids are risk factors for CMV infection. CMV positivity was 9.8% in the tissue samples of patients by IHC and 1.2% by H&E. CMV DNA was detected in 63% of tissue and 58.5% of plasma samples. The sensitivity and negative predictive value (NPV) for qPCR were excellent (100.0%), while the specificity and positive predictive value (PPV) for tissue were low (41.9% and 15.7%, respectively). Similarly, sensitivity and NPV in plasma were higher (100.0%) for qPCR, while specificity and PPV were low (48.6% and 24.0%, respectively). The viral load was ≥ 392 copies/mg in tissue (sensitivity 100.0% and specificity 83.6%) and ≥ 578 copies/mL (895 IU/mL) in plasma (sensitivity 66.7% and specificity 100.0%), ensuring optimal diagnosis.
Conclusions The qPCR method can potentially enhance patient management by timely identifying CMV colitis in UC patients. However, exclusive reliance on qPCR positivity for diagnosis can lead to overdiagnosis, which in turn may result in unnecessary antiviral therapy. To improve diagnostic specificity, quantification of CMV DNA is helpful, although standardization is required.
Publisher
Research Square Platform LLC