title: 22q11 deletions in fetuses with malformations of the outflow tracts or interruption of the aortic arch: impact of additional ultrasound signs.
abstract: OBJECTIVE
  One hundred and forty-one consecutive cases of malformations of the outflow tracts or interrupted aortic arch (IAA), detected by fetal echocardiography, underwent detailed anatomy scan, karyotyping and fluorescence in situ hybridization analysis (FISH) to detect the prevalence of 22q11 microdeletion and to evaluate neonatal clinical findings and outcome according to the presence of the genetic defect. Then, we sought to investigate whether some prenatal ultrasound findings could help identify fetuses at higher risk of carrying the 22q11 microdeletion.
  
  
  METHODS
  Echocardiography and FISH for the DiGeorge critical region (22q11) were performed in all cases.
  
  
  RESULTS
  22q11 microdeletion was detected in 28 of 141 fetuses (19.8%). Intrauterine growth restriction (IUGR) appeared to be associated with the worst prognosis, being present in 2/2 intrauterine fetal deaths and 5/6 post-natal deaths. IUGR, additional aortic arch anomalies and thymic hypo/aplasia were significantly more frequent in fetuses with 22q11 microdeletion (p=0.011, 0.011 and <0.0001, respectively). Prenatal ultrasound thymus examination, performed on the last 84 fetuses, showed 75% sensitivity and 94% specificity. The combination of 2 predictors, namely, thymus defects and IUGR associated with additional aortic arch anomalies reached more than 90% sensitivity and 100% specificity.
  
  
  CONCLUSIONS
  Our study demonstrates that 22q11 microdeletion occurs in 20% of malformations of the outflow tracts and IAA type B, as detected in utero, and that this association is significantly predicted by the presence of associated ultrasound findings: thymic hypo/aplasia, IUGR and additional aortic arch anomalies. The feasibility of a correct prenatal diagnosis should enable clinicians to provide the couple with further informative counselling and to plan adequate post-natal medical interventions.
authors.affiliation: Department of Obstetrics and Gynecology, Hospital, Bari, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Volpe
authors.forename: Maurizio
authors.initials: M
authors.lastname: Marasini
authors.forename: Gilda
authors.initials: G
authors.lastname: Caruso
authors.forename: Andrea
authors.initials: A
authors.lastname: Marzullo
authors.forename: Antonia Lucia
authors.initials: AL
authors.lastname: Buonadonna
authors.forename: Paolo
authors.initials: P
authors.lastname: Arciprete
authors.forename: Salvatore
authors.initials: S
authors.lastname: Di Paolo
authors.forename: Gennaro
authors.initials: G
authors.lastname: Volpe
authors.forename: Mattia
authors.initials: M
authors.lastname: Gentile
mesh_terms: D000015:Abnormalities, Multiple / Q000175:diagnosis / Q000196:embryology / Q000453:epidemiology* / Q000235:genetics; D001011:Aorta / Q000002:abnormalities / Q000000981:diagnostic imaging; D002872:Chromosome Deletion; D002892:Chromosomes, Human, Pair 22; D004452:Echocardiography; D005260:Female; D005317:Fetal Growth Retardation / Q000453:epidemiology; D005865:Gestational Age; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000196:embryology / Q000453:epidemiology* / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D007621:Karyotyping; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D011296:Prenatal Diagnosis; D015995:Prevalence; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal / Q000592:standards