title: Toxoplasma gondii isolates: multilocus RFLP-PCR genotyping from human patients in Sao Paulo State, Brazil identified distinct genotypes.
abstract: This study investigated the genetic characteristics of Toxoplasma gondii samples collected from 62 patients with toxoplasmosis in Sao Paulo State, Brazil. DNA samples were isolated from blood, cerebrospinal fluid and amniotic fluids of 25 patients with cerebral toxoplasmosis and AIDS, two patients with acute toxoplasmosis, 12 patients with ocular toxoplasmosis, six newborns with congenital toxoplasmosis and 17 pregnant women with acute infection. Diagnosis of toxoplasmosis was based in clinical, radiological and laboratory features. Genotyping was performed using multilocus PCR-RFLP genetic markers including SAG1, SAG2, 5'- and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, C22-8, c29-2, L358, PK1 and Apico. Among the 62 clinical samples, 20 (32%) were successfully genotyped at eight or more genetic loci and were grouped to three distinct genotypes. Eighteen samples belonged to ToxoDB Genotype #65 and the other two samples were identified as ToxoDB Genotypes #6 and #71, respectively (http://toxodb.org/toxo/). Patients presenting Genotypes #6 and #71 had severe and atypical cerebral toxoplasmosis, characterized by diffuse encephalitis without extensive brain lesions. These results indicate that T. gondii Genotype #65 may have a high frequency in causing human toxoplasmosis in Sao Paulo State, Brazil. This unusual finding highlights the need to investigate the possible association of parasite genotypes with human toxoplasmosis.
authors: Laboratório de Parasitologia, Instituto Adolfo Lutz, SP, Brazil.
authors: Isabelle Martins Ribeiro
authors: IM
authors: Ferreira
authors: Jose Ernesto
authors: JE
authors: Vidal
authors: Cinara de Cássia Brandão
authors: Cde C
authors: de Mattos
authors: Luiz Carlos
authors: LC
authors: de Mattos
authors: Daofeng
authors: D
authors: Qu
authors: Chunlei
authors: C
authors: Su
authors: Vera Lucia
authors: VL
authors: Pereira-Chioccola
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000653:Amniotic Fluid / Q000469:parasitology; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D016054:DNA, Protozoan / Q000097:blood / Q000134:cerebrospinal fluid / Q000302:isolation & purification; D005260:Female; D005819:Genetic Markers; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods*; D012150:Polymorphism, Restriction Fragment Length; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic / Q000453:epidemiology / Q000469:parasitology; D014122:Toxoplasma / Q000145:classification* / Q000235:genetics*; D014123:Toxoplasmosis / Q000453:epidemiology / Q000469:parasitology*; D055815:Young Adult
chemical_list: D016054:DNA, Protozoan; D005819:Genetic Markers