Herpesvirus Infections of Intestinal Tract in the Patients with Intestinal Graft-Versus-Host Diseases: Laboratory Diagnosis Based on DNA Detection By Real-Time Quantitative PCR in Feces Samples

Background: Intestinal herpesvirus disease remains one of the major causes of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). There is lack of useful methods for etiological diagnosis of intestinal herpesvirus diseases. Here, we evaluated the efficiency of detecting herpesvirus in feces samples via real-time quantitative PCR (RQ-PCR) for diagnosis of intestinal herpesvirus diseases after allo-HSCT.

Methods: This was a multicenter, prospective study. Patients with refractory diarrhea after intestinal graft-versus-host diseases (GVHD) were enrolled in this study. Laboratory tests which consisted of morphologic examination, immunohistochemistry, in situ hybridization, and RQ-PCR of tissue homogenate were used to detect viral pathogens including cytomegalovirus (CMV), epstein-Barr virus (EBV), herpes simplex virus (HSV)-I, HSV-II, varicella zoster virus (VZV), adenovirus (ADV) and human herpes virus (HHV)-6, HHV-7. These viruses aforementioned were also detected in feces and blood samples.

Results: One hundred and seven patients with refractory diarrhea after intestinal GVHD were enrolled between January 2016 and December 2020. Based on the detection of viruses in biopsy specimens, 75 patients were diagnosed as intestinal infectious diseases including 64 accompanying with intestinal GVHD. CMV was the most frequent pathogen of intestinal infectious diseases (53.8%), followed by EBV (36.5%), bacteria (3.4%) and others (6.3%). For diagnosis of intestinal CMV diseases, the sensitivity and specificity of RQ-PCR in feces samples were better than those of blood (sensitivity: 96.9% v.s. 72.5%, p=0.004; specificity: 93.6% v.s. 75.8%, p=0.035). Similarly, the sensitivity of RQ-PCR in feces and blood samples were 88.2% and 21.9% (p<0.001) and the specificity were 98.5% and 86.3% (p=0.032) for diagnosis of intestinal EBV diseases.

Conclusion: Intestinal infectious diseases were one of the main causes of refractory diarrhea after intestinal GVHD. Herpesviruses, especially CMV and EBV, were the most common pathogens. Herpesvirus-DNA detection by RQ-PCR in feces samples was a useful diagnostic method for intestinal herpesviruses diseases.