Frequency of CMV reactivation in patients with autologous and allogeneic hematopoietic stem cell transplantation

Introduction: Hematopoietic stem cell transplantation; It is a form of treatment that provides curative treatment in malignant hematological diseases, some benign hematological diseases, and some solid organ tumors. The most common cause of post-transplant morbidity and mortality is infections. CMV is a common pathogen in post-transplant viral infections. Objective: To determine the prevalence of CMV viremia after transplantation in patients with autologous and allogeneic HSCT followed in our center and to identify risk factors that may lead to viremia. Materials and Methods: 166 autologous transplant patients, 84 allogeneic transplant patients, aged 18 years and over, who had HSCT between February 2014 and November 2021 were included. The patients were divided into two groups as allogeneic and autologous according to the type of transplantation. Demographic characteristics of the patients, primary hematological diseases before transplantation, pre-transplant preparation regimens, CMV IgG values, post-transplant CMV PCR results were retrospectively analyzed using the electronic file system MIA MED. Patients with CMV PCR>150 copies/mL were considered positive. Results: CMV IgG was found in 98.1% in patients with autologous HSCT and 100% in patients with allogeneic HSCT. CMV viremia was observed in 29 (17.5%) of patients with autologous HSCT and 64 (76.2%) of allogeneic patients. IV ganciclovir was given to two of 29 patients with autologous HSCT who were followed up with CMV viremia, and viremia regressed in 27 patients without treatment. It was determined that 65.5% of CMV viremia in patients with autologous HSCT occurred in the first 30 days, 31% between 31-90 days and 3.5% over 90 days. We found that CMV viremia was significantly higher in patients with allogeneic HSCT than in patients with autologous HSCT (p=0.0001). We determined that CMV PCR positivity in patients with autologous HSCT differs statistically significantly in patients older than 50 years of age compared to patients younger than 50 years old. (p=0.03). We determined that it did not differ according to gender, regimen and diagnosis variables (p>0.05). Conclusion: Turkey is an endemic region for CMV. CMV is a common viral pathogen after HSCT. We found that the probability of CMV viremia in patients with allogeneic HSCT is significantly higher than in patients with autologous HSCT (p=0.0001). CMV PCR positivity after HSCT is mostly seen in the first 90 days in patients with autologous HSCT. CMV viremia after autologous HSCT is usually self-limiting and does not require antiviral therapy. We determined that CMV viremia in patients with autologous HSCT differed significantly in patients over 50 years of age compared to patients younger than 50 years old (p=0.03). We determined that gender, preparation regimen, and disease diagnosis were not significant for CMV viremia (p>0.05). Key words: Hematopoietic stem cell transplantation, CMV, autologous, allogeneic