Herpes Virus Reactivation in Lymphoma Patients During and After Autologous Hematopoietic Stem Cell Transplantation

Abstract

Aim. To assess the detection rate of human herpes virus DNA (of cytomegalovirus, herpes simplex virus types 1 and 2 [HSV-1/2], human herpes virus type 6 [HHV-6], and Epstein-Barr virus) in different biological environments at different stages of autologous hematopoietic stem cell transplantation (auto-HSCT) as well as the effect of immune factors on reactivation of viruses under study. Materials & Methods. From 2019 to 2021 the study enrolled 87 lymphoma patients during and after auto-HSCT. Virological monitoring was performed on biological fluids (blood, saliva, urine, etc.) prior to conditioning regimen on Day 0 as well as on Day +5 and Day +10 after auto-HSCT. On these days (Day 0, Day +5, and Day +10) the immune factors (IgM, IgG, and IgA levels and pattern of lymphocyte subpopulation in peripheral blood) in 15 % (14/87) of patients were assessed in terms of their effect on herpes virus reactivation. Results. The overall rate of viral DNA detection increased from 26 % (26/87) to 42 % (37/87) of cases in the period of granulocytopoietic recovery. The most frequent were HHV-6 and HSV-1/2 reactivations reported in 23 % (20/87) and 16 % (14/87) of cases, respectively. The median B-lymphocyte proportion in peripheral blood of patients with herpes virus reactivation was 0.26 %, whereas in patients without reactivation it was 6.7 % (p = 0.019). The median absolute B-lymphocyte count in the cohort of patients with detected viral DNAs was 0.001 ^x 10⁹/L, whereas in patients without them it was 0.098 ^x 10⁹/L (p = 0.026). Conclusion. A high rate of herpes virus DNA detection in lymphoma patients after auto-HSCT affected neither transplant engraftment nor transplantation mortality. Immune predictors of virus infection reactivation were the decreasing proportion of B-cells in the total lymphocyte count and the absolute B-lymphocyte count in the peripheral blood prior to auto-HSCT.