298 - Pre-natal screening of chromosomal defects.Updated results of a study carried out at the RomeHealth District from Jan 2003 to Jan 2008
Autor(s): M.R. Boccolini, R. De Angelis, R. Mattei, M.A. Spina, R. Impera, V. Sargentini
Issue: RIMeL - IJLaM, Vol. 5, N. 4, 2009 (MAF Servizi srl ed.)
Page(s): 298-303
Background. Recently there has been a need to develop a good, inexpensive and non-invasive method to estimate the genetic risk of the total gestational population.It was demonstrated a few years ago that the fetal nuchal translucency and the biochemical markers of themother’s serum (free-βHCG and PAPP-A, that is, Pregnancy associated plasma protein-A) during the firsttrimester have allowed for the identification of 85%to 90% of the fetuses suffering from trisomy 21 syn-drome. Furthermore, the new methods, which permit themeasuring of the biochemical markers within 30 minutes from the taking of a mother’s blood sample,have allowed the introduction of a new screening method that can evaluate the risk of chromosomaldeficiency in only one visit (OSCAR - One-Stop Clinics for Assessment of Risk). Patients and methods. The study was comprised of 7727 patients (age range 20-46 years). The nuchal translucency measurement was performed following the criteriaof the London Fetal Medicine Fundation, and thematernal serum levels of free-βHCG and PAPP-A weremeasured by a fluoro-immuno-enzymatic method usingthe Kryptor analyser by Dasit. Results. An index risk >1/300 was obtained in 287 ca-ses. Among 237 cases put through an invasive diagnosis, 35 reported aneuploidy. Eighteen patients were lessthan 35 years old (9 with trisomy 21, 2 with trisomy 13, 2 with trisomy 18, 2 with monosomia X, 3 withmosaicism). Conclusions. The results obtained are consistent with thedata reported in the literature and demonstrate that thescreening related to fetal chromosomal pathology performed during the first trimester of pregnancy is moreeffective than that proposed by the Italian NationalHealth System in that it permits screening the total gestational population, thereby limiting the need to useinvasive methods to only those cases with an index riskcut-off >1/300.
Key-words: prenatal diagnosis, nucal translucency, OneStop Clinics for Assessment of Risk (OSCAR).