title: Detection of Toxoplasma gondii in venous blood from AIDS patients by polymerase chain reaction.
abstract: Detection of Toxoplasma gondii in blood by means of the polymerase chain reaction (PCR) may facilitate the diagnosis and follow-up of cerebral toxoplasmosis in patients with AIDS. We evaluated this approach with seven patients with tissue culture-proven parasitemia, 14 patients with presumptive cerebral toxoplasmosis, and 17 healthy human immunodeficiency virus-positive controls. Each sample of blood was assayed on three different occasions by a PCR assay based on detection of the gene encoding the P30 surface protein. A positive PCR diagnosis required positivity in at least two of the three PCR tests. None of the controls had a positive PCR diagnosis, but six of the seven patients with parasitemia did. Cerebral toxoplasmosis was confirmed in 13 of the 14 patients with a presumptive diagnosis; diagnosis by PCR was positive before treatment for 9 of these 13 patients, whereas tissue culture was positive for only 1 patient. During treatment, blood samples were taken from 14 patients at regular intervals until day 12. PCR diagnosis became negative on ethidium-stained gels, but persistent signals were observed after hybridization, in some cases, for up to 12 days after initiation of therapy. PCR on venous blood could thus be a sensitive and noninvasive method for the diagnosis of cerebral and disseminated toxoplasmosis in AIDS patients and could be a potential tool for monitoring the effects of treatment.
authors.affiliation: Laboratoire de Parasitologie, Hôpital Cochin, Paris, France.
authors.forename: J
authors.initials: J
authors.lastname: Dupouy-Camet
authors.forename: S L
authors.initials: SL
authors.lastname: de Souza
authors.forename: C
authors.initials: C
authors.lastname: Maslo
authors.forename: A
authors.initials: A
authors.lastname: Paugam
authors.forename: A G
authors.initials: AG
authors.lastname: Saimot
authors.forename: R
authors.initials: R
authors.lastname: Benarous
authors.forename: C
authors.initials: C
authors.lastname: Tourte-Schaefer
authors.forename: F
authors.initials: F
authors.lastname: Derouin
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000097:blood / Q000175:diagnosis* / Q000469:parasitology; D000818:Animals; D000953:Antigens, Protozoan; D001483:Base Sequence; D016054:DNA, Protozoan / Q000097:blood / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods* / Q000706:statistics & numerical data; D015800:Protozoan Proteins / Q000235:genetics; D012680:Sensitivity and Specificity; D014122:Toxoplasma / Q000235:genetics* / Q000302:isolation & purification*; D016781:Toxoplasmosis, Cerebral / Q000150:complications / Q000175:diagnosis* / Q000469:parasitology
chemical_list: D000953:Antigens, Protozoan; D016054:DNA, Protozoan; D015800:Protozoan Proteins; C047168:SAG1 antigen, Toxoplasma