Serological Evaluation of Anti-Toxoplasma gondii Antibodies in Patients with Acute Leukemia and Lymphoma through Chemotherapy.

Background Toxoplasma gondii is a protozoan parasite that belongs to the family Coccidae. We aimed to evaluate IgG avidity and the changes of anti-Toxoplasma immunoglobulins M (IgM) and G (IgG) in patients with acute leukemia and lymphoma. Methods Ninety eight patients with Acute myeloid leukemia (AML), Acute Lymphoblastic Leukemia (ALL) and lymphoma, selected from patients referring to Imam Reza Hospital of Tabriz (38°04'N 46°18'E), in terms of the presence of anti-Toxoplasma IgM, IgG, IgG avidity antibodies and the major risk factors were evaluated. Results The results of pre-chemotherapy evaluation showed that of the examined patients, only two cases, one patient with ALL and another patient with lymphoma, had a positive IgM titer. Overall, 46 cases had positive IgG titers, including 20 patients with AML, 15 patients with ALL and 11 patients with lymphoma. Three (3.06%) patients were positive for anti-T. gondii IgM and one of them was with new infection of toxoplasmosis in lymphoma patients. The post-chemotherapy IgG titer evaluation showed 46 [46.9% (95% CI 37.4-56.7)] positive IgG cases that this result was similar to the result of pre-treatment phase. One [1% (95% CI 0.2-5.6)] positive IgG avidity case was detected using ELISA method, in a patient with lymphoma whose IgM was also positive. There was no significant difference between the type of leukemia and the history of contact with cat. Conclusion Performing specialized tests to diagnose toxoplasma infection before starting treatment, in immunodeficiency patients who undergo chemotherapy, is necessary; therefore, these tests should be considered in therapeutic protocols.