Objective: This study aimed to investigate the role of human herpesvirus (HHV) infection in refractory intestinal graft-versus-host disease (GI-GVHD) after hematopoietic stem cell transplantation (HSCT) and its diagnosis and treatment. Methods: This study retrospectively analyzed patients presenting with refractory GI-GVHD after allogeneic HSCT (allo-HSCT) with concomitant colonoscopy and mucosal biopsy at Lu Daopei Hospital, Yanda, Hebei, from March 2022 to July 2024. Human herpesvirus 6 (HHV6), HHV7, cytomegalovirus (CMV), and Epstein-Barr virus (EBV) detection with the RQ-PCR method. The intestinal mucosa was pathologically assessed and immunohistochemistry was utilized to detect the CMV early antigen, CMV late antigen, and EBV by in situ hybridization. Results: This study included 42 patients, consisting of 25 males and 17 females with a median age of 26 (1-59) years. All were histopathologically diagnosed as GI-GVHD. Among them, 34 (81.0%) cases had combined viral enteritis, with 52.4% positive for EBV, 38.1% positive for HHV6, 26.2% positive for CMV, and 14.3% positive for HHV7. Further, 17 (40.5%) cases had mixed viral infections, including 5 EBV+ HHV6, 3 CMV+HHV6, 3 CMV+EBV, 2 CMV+EBV+HHV6, 2 EBV+HHV6+HHV7, 1 EBV+HHV7, and 1 HHV6 + HHV7 cases. Furthermore, 17 (40.5%) had a single viral infection, including 9 EBV, 3 CMV, 3 HHV6, and 2 HHV7 cases. Moreover, 17 (40.5%) patients exhibited a positive histopathological viral test, including 7 (16.6%) CMV-positive and 12 (28.5%) EBV-positive cases. The same positive virus was detected in the feces of all 34 patients with positive tissue homogenate virus, and the positive rate of the same virus in the blood was 17.6%. Tissue homogenized virus testing was utilized as the diagnostic criterion for enterocolitis: blood tests for CMV, EBV, HHV6, and HHV7 demonstrated a sensitivity of 45.4%, 4.5%, 6.3%, and 0%, and specificity of 90.3%, 95%, 100%, and 110%, respectively. Additionally, fecal tests for CMV, EBV, HHV6, and HHV7 demonstrated a sensitivity and specificity of 100%. Treatment based on etiology caused ORR and CR rates for diarrhea of 76.1% (32/42) and 66.6% (28/42), respectively. The median follow-up of 42 patients was 13 (1 - 49) months, and 28 patients survived, with an expected 2-year survival rate of 61.9%. Conclusion: In addition to GVHD itself, intestinal human herpesvirus infection is one of the reasons for the refractory nature of GI-GVHD. Viral testing in blood and tissues reveals significant segregation, and the possibility of comorbid viral enteritis cannot be excluded even if a patient with GI-GVHD tests negative for blood viruses.
目的： 探讨人类疱疹病毒（HHV）感染在造血干细胞移植后难治性肠道移植物抗宿主病（GI-GVHD）中的作用及诊断和治疗。 方法： 对2022年3月至2024年7月，于河北燕达陆道培医院行异基因造血干细胞移植（allo-HSCT）治疗后出现难治性GI-GVHD并行结肠镜检查及黏膜活检的42例患者资料进行回顾性分析；采用RQ-PCR方法检测组织匀浆HHV6、HHV7、巨细胞病毒（CMV）、EB病毒（EBV）；肠黏膜进行病理检查并采用免疫组化方法检测CMV早期抗原、CMV晚期抗原，原位杂交法检测EBV。 结果： 42例患者纳入研究，男25例，女17例，中位年龄26（1~59）岁，均经组织病理诊断为GI-GVHD。其中34例（81.0%）合并病毒性肠炎，EBV阳性率52.4%，HHV6阳性率38.1%，CMV阳性率26.2%，HHV7阳性率14.3%。17例（40.5%）为混合病毒感染，包括5例EBV+HHV6，3例CMV+HHV6，3例CMV+EBV，2例CMV+EBV+HHV6，2例EBV+HHV6+HHV7，1例EBV+HHV7，1例HHV6+HHV7。17例（40.5%）为单一病毒感染，其中EBV感染9例、CMV感染3例、HHV6感染3例、HHV7感染2例。17例（40.5%）患者组织病理病毒检测阳性，包括7例（16.6%）CMV阳性，12例（28.5%）EBV阳性（其中2例CMV、EBV双阳性）。34例组织匀浆病毒阳性患者均可于粪便中检测到相同病毒，血液相同病毒阳性率17.6%。以组织匀浆病毒检测为肠炎诊断标准，血液检测CMV、EBV、HHV6、HHV7敏感性分别为45.4%、4.5%、6.3%、0%，特异性分别为90.3%、95.0%、100%、100%，粪便检测CMV、EBV、HHV6、HHV7敏感性和特异性均为100%。基于病因学进行治疗，腹泻的总反应率和完全缓解率分别为76.1%（32/42）和66.6%（28/42）。42例患者中位随访时间为13（1~49）个月，28例患者存活，2年预期生存率为61.9%。 结论： 除GVHD本身外，肠道HHV感染是GI-GVHD难治性的原因之一。血液和组织中病毒检测呈明显分离现象，即使GI-GVHD患者血液病毒检测阴性，也不能排除合并病毒性肠炎的可能。.
Keywords: Allogeneic hematopoietic stem cell transplantation; Gastrointestinal; Graft-versus-host-disease; Human herpesvirus infection.