title: Early detection of Toxoplasma infection by molecular monitoring of Toxoplasma gondii in peripheral blood samples after allogeneic stem cell transplantation.
abstract: BACKGROUND
  Isolated case reports have shown that recipients of allogeneic hematopoietic stem cell transplants (HSCTs) who develop toxoplasmosis may have circulating Toxoplasma gondii DNA in peripheral blood before the onset of clinical symptoms.
  
  
  METHODS
  We prospectively studied 106 T. gondii-seropositive adult recipients of HSCTs for the incidence of reactivation of toxoplasmosis in the first 6 months after transplantation. Toxoplasmosis infection (TI) was defined by a positive result of polymerase chain reaction (PCR) of peripheral blood specimens, whereas toxoplasmosis disease (TD) was defined as an invasive infection.
  
  
  RESULTS
  The incidence of TI was 16% (95% confidence interval [CI], 8%-21%), whereas the incidence of TD was 6% (95% CI, 1%-10%). In the 16 patients with TI, the incidence of disease was 38%, whereas it was 0% in patients without TI (P<.0001). In most patients, the onset of TD or treatment for TI was preceded by an increase in the parasite load in peripheral blood samples, as determined by quantitative PCR.
  
  
  CONCLUSIONS
  Toxoplasmosis occurs more commonly after HSCT than has previously been suggested, and routine PCR testing of peripheral blood specimens may be an appropriate tool for guiding preemptive therapy in patients at very high risk of developing invasive disease.
authors.affiliation: Division of Clinical Hematology, Hospital de la Sant Creu i Sant Pau, Barcelona, Spain. rmartino@hsp.santpau.es
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Martino
authors.forename: Stéphane
authors.initials: S
authors.lastname: Bretagne
authors.forename: Hermann
authors.initials: H
authors.lastname: Einsele
authors.forename: Johan
authors.initials: J
authors.lastname: Maertens
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Ullmann
authors.forename: Rocio
authors.initials: R
authors.lastname: Parody
authors.forename: Ulrike
authors.initials: U
authors.lastname: Schumacher
authors.forename: Cécile
authors.initials: C
authors.lastname: Pautas
authors.forename: Koen
authors.initials: K
authors.lastname: Theunissen
authors.forename: Christine
authors.initials: C
authors.lastname: Schindel
authors.forename: Carmen
authors.initials: C
authors.lastname: Muñoz
authors.forename: Nuria
authors.initials: N
authors.lastname: Margall
authors.forename: Catherine
authors.initials: C
authors.lastname: Cordonnier
mesh_terms: D000328:Adult; D000818:Animals; D016054:DNA, Protozoan / Q000097:blood*; D006403:Hematologic Tests; D006801:Humans; D016133:Polymerase Chain Reaction; D033581:Stem Cell Transplantation / Q000009:adverse effects*; D014122:Toxoplasma / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D014123:Toxoplasmosis / Q000175:diagnosis* / Q000453:epidemiology / Q000469:parasitology; D014184:Transplantation, Homologous / Q000009:adverse effects
chemical_list: D016054:DNA, Protozoan