Quality Control for the Molecular Diagnosis of Toxoplasmosis

摘要: Toxoplasmosis is an endemic parasitic disease due to the protozoon Toxoplasma gondii. The definitive host cat, in which parasite develops intestinal epithelium, before being eliminated as oocysts faeces. When oocysts, for example contaminated soil, are ingested by humans, other mammals or birds, they pass through stomach and excyst intestine; released sporozoites invade wall give rise generalized infection (Remington & Desmonts, 1995; Wong Remington, 1993). Two tissue stages important pathogenesis: tachyzoites bradyzoites. Initially, consists mainly of rapidly dividing tachyzoites. Then, with developing immunity, persistent cysts containing hundreds slowly multiplying bradyzoites develop, especially muscle brain. This ability live inside cells without destroying them allows evasion immunity development a chronic stage infection, lasting years. Intermediate hosts become infected either ingesting water foodstuff cat faeces raw undercooked meat cysts. T. gondii responsible generally benign infections except when occurs pregnant women (congenital toxoplasmosis) immunocompromised individuals, such human immunodeficiency virus-positive grafted patients, cases vital prognosis may be involved. In certain countries Europe, including France, toxoplasmosis regarded serious health problem. prevalence acquired adults 44%, estimated yearly incidence contamination during pregnancy congenital high, respectively, 6-7/1000 0.1% births (Berger et al., 2008, King 2008). Prevention (CT), prenatal diagnosis (PND), has national policy France since 1978 (Thulliez, 1992). Serological screening follow-up established non-immunized women, associated monthly ultrasound examinations. PND proposed case seroconversion between 6 38 weeks amenorrhea. For this, PCR-based molecular diagnostic tests using amniotic fluid, introduced early 90's, have need cordocentesis, competed more classical biological methods. Wherever it been implemented, CT clearly improved outcome children (reviewed (Bastien, 2002)).