Serology for Toxoplasma in Immunocompromised Patients: Still Useful?

Toxoplasmosis is a life threatening opportunistic infection in immunocompromised patients. PCR allows detection of T. gondii DNA but does not inform about the serological status patient nor chronic infection. Serology only tool that identification, among patients, those who are at risk potential Toxoplasma reactivation. A simple serologic screening SOT donors and recipients can identify mismatch (D+/R–) allow prevention high morbidity mortality. Screening donor allo-HSCT graduation reactivation infection, which highest for seropositive receiving seronegative graft (D–/R+). should best be combined with serology follow-up patients clinical represents one most common comorbidity factors solid organ or hematopoietic stem cell transplant as well other In past decades, availability performance molecular tools diagnosis exclusion toxoplasmosis these have greatly improved. However, if accurately used, remains complementary essential diagnostic physicians medical parasitologists management well. It required determination immunological against Toxoplasma. also helps diagnose monitor complex cases New perspectives available to further enhance their yield ease use. avidity reflects strength binding IgG antibodies antigen. increases time, due maturation hypervariable regions antibodies. testing an interesting distinguish between recent when both gondii-specific IgM detected serum sample. Indeed, result indicates dating from more than 3 5 months according assay. latent stage gondii, responsible persistence parasite human body. results evolution tachyzoite stage. Bradyzoites grouped into intracellular cysts, persist lifelong various tissues, including central nervous system, eyes, muscles. reactivate tachyzoites, especially case immunosuppression. resistant form found environment. sexual reproduction felids. Oocysts contained sporozoites, infective stages parasite, evolve tachyzoites. primary corresponds first contact gondii. Contamination occur by ingestion of: (i) oocysts through contaminated hands insufficiently washed raw vegetables fruits, (ii) cysts undercooked meat. Primary mostly asymptomatic, immunocompetent cases, nonspecific symptoms, such fever, asthenia, lymphadenopathies, seriously chorioretinitis, observed. it usually transmission following transplantation. prevented hygiene diet measures, chemoprophylaxis. often via cysts. severe forms, cerebral, ocular, pulmonary ones. Disseminated commonly described this population. its consequences replicative capable infecting any type nucleated dissemination manifestations disease.