ACTIVATION OF T. GONDII INFECTION AFTER ALLOGENEIC TRANSPLANTATION OF HEMATOPOIETIC STEM CELLS: DEPENDENCE ON TIME OF TRANSPLANTATION AND SEROLOGICAL STATUS OF THE PATIENTS

Abstract

The article focuses on aspects of T. gondii reactivation/reinfection in patients undergoing allogeneic hematopoietic stem cell transplantation (alloHSCT). We have observed 297 patients who received conditioning therapy and allogeneic grafts due to different oncohematological or lymphoproliferative diseases (1 to 60 years old, at a mediane of 19 years). Conditioning regimens were either myeloablative (35%), or non-myeloablative (65%). DNA diagnostics of T. gondii was performed on a regular basis at 0 to 6 months post-HSCT. IgG and IgM antibodies against T. gondii were determined in 78 patients before HSCT, as well as in their donors. T. gondii DNA post-transplant proved to be positive in 13% of blood specimens, 9% of cerebrospinal liquor samples, 11% of bronchoalveolar cell lavages, and in 5% of urine sediments. In adolescent patients (10 to 14 years old), an increased prevalence of T. gondii was found in patients who received myeloablative treatment (p = 0.01). When assessing posttransplant dynamics of T. gondii, we have revealed distinct increase in the pathogen excretion within 1st month after HSCT (p = 0.03). Finally, initial presence of IgG antibodies against T. gondii in the patients was associated with lower incidence of the pathogen reactivation post-transplant.

Keywords

• hematopoietic stem cell transplantation
• toxoplasma gondii
• reactivation
• dna diagnostics
• igg antibodies