Real-time quantitative PCR analysis of endoscopic biopsies for diagnosing CMV gastrointestinal disease in non-HIV immunocompromised patients: a diagnostic accuracy study

Cytomegalovirus gastrointestinal diseases (CMV-GIDs) are end-organ diseases of the gastrointestinal (GI) tract caused by CMV in immunocompromised patients. We aimed to evaluate the performance of quantitative polymerase chain reaction (qPCR) on endoscopic biopsies. We retrospectively reviewed the qPCR data on endoscopic biopsies in nonhuman immunodeficiency virus (HIV) immunocompromised patients between January 2009 and May 2015. The performance of the qPCR for CMV-GID was evaluated with the sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC). A total of 195 patients were included, and 28 patients with confirmed CMV-GID were identified. The AUROC of the qPCR was 0.935 (95% confidence interval [CI], 0.885 to 0.985), the sensitivity was 89.3% (95% CI, 71.8 to 97.7%), and the specificity was 85.6% (95% CI, 79.4 to 97.6%) with a cutoff value of 180 copies/μg DNA. The proportion of patients with inflammatory bowel disease in the histopathology-negative, PCR-positive group was smaller than that in the histopathology-positive group (10.7 vs 35.0%, p = 0.026), but other characteristics were not significantly different. The use of qPCR on endoscopic biopsies demonstrated good diagnostic performance for detecting CMV in non-HIV immunocompromised patients. It may increase the diagnostic yield when combined with a conventional histopathology.