This page was last modified on 7 March 2015, at 23:58.



Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii


Individual at risk






Guidance at CT



Guidance at WORK-UP

Recommended work-up testing

Toxoplasmosis-IgM and IgG


Testing outcomes and recommendations

1) Toxoplasmosis IgM = negative AND Toxoplasmosis IgG = positive or negative

Donor can be cleared


2) Toxoplasmosis IgM = positive AND Toxoplasmosis IgG = positive

Avidity testing should be performed to measure the binding strength of specific antibodies to toxoplasmosis antigens. This allows estimation of the time point of primary infection as well as to distinguish between acute and chronic infection.

Toxoplasmosis NAT-testing (PCR) from donor peripheral blood is not relevant, since negative PCR does not exclude relevant infection/parasitemia.

The transplant centre should be informed and clearance or deferral may be appropriate according to avidity test


2) Toxoplasmosis IgM = positive AND Toxoplasmosis IgG = negative

Further laboratory testing is necessary (e.g. Immunoblot/ISAGA) to verify if result is due to acute infection or non-specific binding.

No clearance should be given until clarification is obtained.

Justification for guidance

Toxoplasmosis is a recognised complication of immuno-suppression post-transplant.



APA Recommendations of the Center for International Blood and Marrow Transplant Research (CIBMTR®), the National Marrow Donor Program (NMDP), the European Blood and Marrow Transplant Group (EBMT), the American Society of Blood and Marrow Transplantation (ASBMT), the Canadian Blood and Marrow Transplant Group (CBMTG), the Infectious Disease Society of America (IDSA), the Society for Healthcare Epidemiology of America (SHEA), the Association of Medical Microbiology and Infectious Diseases Canada (AMMI), and the Centers for Disease Control and Prevention (CDC), Tomblyn, M., Chiller, T., Einsele, H., Gress, R., Sepkowitz, K., … Boeckh, M. A. (2009). Guidelines for Preventing Infectious Complications among Hematopoietic Cell Transplant Recipients: A Global Perspective. Biology of Blood and Marrow Transplantation : Journal of the American Society for Blood and Marrow Transplantation, 15(10), 1143–1238. doi:10.1016/j.bbmt.2009.06.019 [1]



Page created 7th March 2015