Genotyping of Toxoplasma gondii strain directly from human CSF samples of congenital toxoplasmosis clinical case

New Microbiol. 2017 Apr;40(2):151-154. Epub 2017 Apr 3.

Abstract

This report describes a case of congenital toxoplasmosis in a newborn in Southern Italy. A pregnant mother had been admitted at the 20th week of her pregnancy on account of pharyngodynia and laterocervical lymphadenopathy. Although serological testing of the mother's serum documented a seroconversion with positive IgG and IgM anti-Toxoplasma antibodies during II trimester, the woman refused to perform prenatal diagnosis for congenital toxoplasmosis. Fetal ultrasound scan already showed mild asymmetrical triventricular hydrocephaly and cerebral calcifications. After birth, real-time PCR on cerebrospinal fluid and blood samples of the newborn showed a positive result for 529bp-repeat element DNA of T. gondii, In addition brain magnetic resonance imaging and computed tomography showed a characteristic diffuse brain tissue loss associated with hydrocephalus. For the first time molecular characterization of T. gondii isolate was performed directly from the newborn's CSF samples by using nested-PCR-RFLP of sag-2 and pk1 genes. The PCR-RLFP analysis revealed that the isolate belongs to the clonal type II, the predominant lineage causing human toxoplasmosis, as confirmed by DNA sequencing.

Keywords: Congenital toxoplasmosis; Genotyping; Nested-PCR-RFLP; Toxoplasma gondii.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Antibodies, Protozoan / blood
  • Base Sequence
  • Cerebrospinal Fluid / parasitology
  • DNA, Protozoan / cerebrospinal fluid
  • DNA, Protozoan / chemistry
  • Female
  • Genotype
  • Genotyping Techniques
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin M / blood
  • Infant, Newborn
  • Polymerase Chain Reaction
  • Polymorphism, Restriction Fragment Length
  • Pregnancy
  • Toxoplasma / classification
  • Toxoplasma / genetics*
  • Toxoplasma / immunology
  • Toxoplasmosis, Congenital / cerebrospinal fluid
  • Toxoplasmosis, Congenital / diagnostic imaging
  • Toxoplasmosis, Congenital / parasitology*

Substances

  • Antibodies, Protozoan
  • DNA, Protozoan
  • Immunoglobulin G
  • Immunoglobulin M