Molecular detection of Toxoplasma gondii in a sample of Iraqi patients with acute leukemia and Stem cell transplantation

Acute leukemia is the most common hematological malignancies; the malignant cells are immature cells that areincapable of performing their immune system functions. Chemotherapy and Hematopoietic stem cell transplantation (HSCT) are the established treatment for a variety of malignant diseases including acute leukemia. After induction chemotherapy and allogeneic bone marrow transplantation there will be suppression of the immunity and the patients will be susceptible for many opportunistic infections or reactivation of latent infections. Opportunistic infections of T.gondii make an important threat to patients with acute leukemia after the use of intense chemotherapy and immunosuppression drugs following allogeneic HSCT. To detection of T.gondiiin patients with acute leukemia after chemotherapy (induction) courses and post allogeneic Stem cell transplantation patients within the first year and determine copy number of T.gondiiin these groups and compare with apparently healthy individual as control group.A prospective study enrolled 61 patients who diagnosed to have acute leukemia. Forty eight of them had received an induction course of chemotherapy, within one month of diagnosis (group I). While the other 13 acute leukemia patients had assessed after bone marrow transplantation within the first year of diagnosis as group II and 30 apparently healthy individuals as control group. The questionnaire form was given to each patient included: age, sex, residence, Job, Virology screen (HBV,HCV),type of acute leukemia,Chronic disease (DM or HT) if present,frequency of Blood transfusion in addition to CBC. Blood samples were collected from all groups. T. gondii DNA was extracted from 1 ml whole blood samples,and then,T. gondii DNA was detected and measured by Taqman quantitative real-time PCR.The serum to measure IgG and IgM antibody specific to T. gondii wasinvestigated in the control group by an enzyme-linked immune assay (ELISA).T. gondii parasitemia was detected in (8.3%) 4 out of 48 group I patient. While negative in group II and control group. The range of T.gondii load was(6.285×103-17.915×103) copy/ml,the mean of the copy numbers 11458.75± 5120.85.The study is of medical importance as it deals with immunocompromised patients,notably those with cell mediated immunity deficiency who are at risk for life threatening opportunistic infections or reactivation,T.gondii should be looked for Leukemic patients at least by routine serological test for early diagnosis and proper treatment of the patient may reduce the complications of infection and promote better prognosis. And Quantitative PCR is used to monitor PBMT patients at risk for T.gondii disease and for a timely start of preemptive therapy.