title: [Analysis of two false positive cases from noninvasive prenatal testing].
abstract: OBJECTIVE
  To track and analyze two false positive cases from non-invasive prenatal testing for potential fetal aneuploidy.
  
  
  METHODS
  The two cases, respectively reported to have XO (+++) and T18 (1/20) XO(+), were analyzed with conventional karyotyping, fluorescence in situ hybridization (FISH) and massively parallel genomic sequencing (MPS).
  
  
  RESULTS
  The first fetus, who was suspected for XO(+++), was verified to have super female syndrome (47,XXX/46,XX) due to confined placental mosaicism by karyotyping of amniotic fluid cells, FISH analysis of placenta and massively parallel sequencing (MPS) of fetal tissue. The second fetus, suspected to have trisomy 18 (1/20) XO(+), was verified to have Turner syndrome by karyotyping, FISH and MPS analyses of umbilical cord blood cells. And the karyotype was 45,X[48]/46, X, der(X) del(X) (p11.21) del(X) (q13.3)[62].
  
  
  CONCLUSIONS
  Non-invasive prenatal testing carries a risk for false positive diagnosis of fetal sex chromosome and trisomy 18. Combined cytogenetic and molecular techniques are required to ensure an accurate diagnosis.
authors.affiliation: Central Laboratory of Taizhou Hospital, Taizhou, Zhejiang 317000, P. R. China. chenxj@enzemed.com.
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Chen
authors.forename: Meizhen
authors.initials: M
authors.lastname: Dai
authors.forename: Weiwu
authors.initials: W
authors.lastname: Shi
authors.forename: Yingqiu
authors.initials: Y
authors.lastname: Pan
authors.forename: Weiguo
authors.initials: W
authors.lastname: Zhang
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Wu
mesh_terms: D000328:Adult; D000782:Aneuploidy; D002869:Chromosome Aberrations; D003951:Diagnostic Errors; D005189:False Positive Reactions; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis* / Q000235:genetics; D006801:Humans; D011247:Pregnancy; D011296:Prenatal Diagnosis; D055815:Young Adult