title: Detection of Toxoplasma gondii from amniotic fluid, a comparison of four different molecular biological methods.
abstract: BACKGROUND
  The infection caused by the parasite Toxoplasma gondii (T. gondii) is often asymptomatic or has mild symptoms. The infection can cause serious problems in pregnant women who acquire the infection during gestation and their fetuses are congenitally infected.
  
  
  METHODS
  We tested 64 amniotic fluid samples for the presence of T. gondii by using fluorescent PCR and DNA fragment analysis. Later we compared four different molecular biological methods for the detection of the presence of T. gondii on same frozen DNA samples. These methods are the conventional PCR, fluorescent PCR with DNA fragment analysis, quantitative real-time PCR with SYBRGreen I and with fluorescence energy transfer hybridization probe detection. We determined the detection limit of these methods.
  
  
  RESULTS
  The conventional PCR and quantitative real-time PCR with SYBRGreen I detection have the detection limit of 1000 parasites, followed by fluorescent PCR with the detection limit of 10-100 parasites. The real-time PCR using fluorescence energy transfer hybridization probes can detect one parasite. This is the most sensitive and the fastest method. We detected 5 T. gondii positive samples with all methods from the studied 64 amniotic fluids.
  
  
  CONCLUSIONS
  All studied molecular biological methods are suitable for the detection of congenital toxoplasmosis. The quantitative real-time PCR based methods are more sensitive, simple and easy to perform these are opening the avenue to find out the effect of the number of parasites on fetal abnormalities.
authors.affiliation: 1st Department of Obstetrics and Gynecology, Semmelweis University, Hungary. nabal@noi1.sote.hu
authors.forename: Bálint
authors.initials: B
authors.lastname: Nagy
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Bán
authors.forename: Artúr
authors.initials: A
authors.lastname: Beke
authors.forename: Gyula Richard
authors.initials: GR
authors.lastname: Nagy
authors.forename: Levente
authors.initials: L
authors.lastname: Lázár
authors.forename: Csaba
authors.initials: C
authors.lastname: Papp
authors.forename: Erno
authors.initials: E
authors.lastname: Tóth-Pál
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Papp
mesh_terms: D000653:Amniotic Fluid / Q000469:parasitology*; D000818:Animals; D016054:DNA, Protozoan / Q000235:genetics; D005260:Female; D006801:Humans; D008967:Molecular Biology; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D014122:Toxoplasma / Q000235:genetics / Q000302:isolation & purification*; D014123:Toxoplasmosis / Q000175:diagnosis* / Q000235:genetics / Q000469:parasitology*
chemical_list: D016054:DNA, Protozoan