HUMAN HERPES VIRUS TYPE 6 INFECTION IN CHILDREN AFTER ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION IN THE REPUBLIC OF BELARUS

Objective: To evaluate the frequency of reactivation of HHV-6 infection in patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT); determine viral load in serum/plasma and associated clinical manifestations; to determine the criteria for initiating anti-viral prophylaxis and etiotropic therapy in patients with this infection in the Republic of Belarus. Methods: Monitoring of polymerase chain reaction (PCR) of blood serum in 42 patients after allo-HSCT. Results: In 31% of patients, HHV-6 DNA was detected in serum/plasma on 14-28 days after allo-HSCT. The concentration of HHV-6 DNA in blood serum was up to 2.3-6.5×103 copies/ml, in 3 patients (18.8%) with the concentration of DNA≥2.3×103 copies/ml, developed clinical manifestations in the form of hepatitis. Regular monitoring of HHV-6 infection revealed reactivation of the infection and, with a viral load of≥100 copies/ml, initiate timely preventive treatment with ganciclovir. Conclusions: HHV-6 DNA is detected in one-third of patients after allo-HSCT and in the form of hepatitis. Timely prevention and therapy with ganciclovir reduce the risk of severe complications and fatal outcomes. Keywords: Children, HHV-6, hematology, stem cells transplantation, hepatitis.