Utility of Cytomegalovirus Quantitative Polymerase Chain Reaction in Tissue Biopsy for the Diagnosis of Cytomegalovirus Gastrointestinal Disease Among Solid Organ Transplant Recipients.

Background: Gastrointestinal (GI) cytomegalovirus (CMV) infection is an important cause of morbidity after solid organ transplantation (SOT), and diagnosis mainly relies on histopathology of GI tissue biopsies. CMV detection by quantitative polymerase chain reaction (qPCR) on tissue biopsy is not routinely performed, but potentially holds many practical advantages.

Methods: We compared the performance of CMV qPCR on fresh GI biopsies to histopathologic identification for the detection of CMV GI disease.

Results: Sixty-one SOT patients with GI symptoms underwent endoscopic assessment, with tissue biopsies obtained. Eleven patients had proven CMV disease by histopathologic detection. Among them, all had a positive qPCR on tissue biopsy (median of 8.7 × 10⁷ IU/mL [interquartile range {IQR} 3.1 × 10⁷, 18.2 × 10⁷]). Of the 49 patients with negative histopathology, 27 (55%) had CMV qPCR-positive tissue biopsy specimens (median of 43 604 IU/mL [IQR 2923, 497 570]). Receiver operating characteristic analysis for optimal threshold value for CMV qPCR on tissue biopsy for diagnosis of proven CMV GI disease was 147 906 IU/mL (sensitivity 100%, specificity 80%, area under the curve = 0.975).

Conclusion: Compared to histopathologic detection, CMV qPCR on GI tissue biopsy is highly sensitive for the diagnosis of CMV GI disease in SOT patients, making it a potentially useful adjunctive diagnostic tool for rapid diagnosis in this population.