Tissue Cytomegalovirus DNA Detection by PCR Is Associated with Increased Endoscopic Activity in Ulcerative Colitis: A...

Area of Science:

• Gastroenterology
• Virology
• Molecular Diagnostics

Background:

• Cytomegalovirus (CMV) reactivation is common in moderate-to-severe ulcerative colitis (UC), especially in steroid-refractory cases.
• The clinical significance of detecting CMV DNA in UC tissue via PCR, without classical histopathological findings, remains debated.

Purpose of the Study:

• To investigate the clinical significance of tissue CMV DNA detection in moderate-to-severe UC patients.
• To evaluate the association between tissue CMV DNA positivity and disease activity, inflammatory markers, and immunosuppressive therapy.

Main Methods:

• Retrospective cohort study of 110 moderate-to-severe UC patients undergoing colonoscopy.
• Analysis of tissue and serum samples for CMV DNA using PCR; tissue positivity defined as ≥250 copies.
• Assessment of endoscopic disease activity using Mayo scores and Rachmilewitz Endoscopic Activity Index.

Main Results:

• Tissue CMV DNA positivity was found in 37.3% of patients, associated with higher clinical and endoscopic activity scores.
• Serum CMV PCR levels were significantly higher in patients with tissue CMV DNA positivity (p < 0.001).
• Recent corticosteroid use was independently associated with tissue CMV DNA positivity; serum CMV PCR showed good diagnostic performance (AUC = 0.82).

Conclusions:

• Tissue CMV DNA positivity in UC correlates with increased clinical and endoscopic disease activity, even without histopathological evidence.
• Molecular CMV detection in colonic tissue offers relevant clinical information, particularly in patients with recent corticosteroid exposure.
• Tissue CMV DNA positivity indicates a molecular association, not necessarily causality or an indication for antiviral therapy; further prospective studies are needed.