PRENATAL DIAGNOSTICS – OUR EXPERIENCES

Cilj je ovoga rada prikazati organizaciju prenatalne skrbi na području riječke regije te iznijeti rezultate dobivene primjenom neinvazivnih (biokemijski test probira za Downov sindrom – DS) i invazivnih metoda (rana amniocenteza – RAC) detekcije kromosomopatija u ploda tijekom drugog tromjesečja trudno}e. Od svibnja 1986. do kolovoza 2004. izvedeno je 1856 RAC-a, a od 1996. godine biokemijskoj analizi seruma u svrhu procjene rizika za DS primjenom dvostrukog (MS-AFP i slobodni -hCG) ili trostrukog testa (MS-AFP, slobodni -hCG i nE) pristupilo je 10.057 trudnica. Aberirani kariotip ustanovljen je u 2,6% provedenih RAC-a, odnosno analiza stanica plodove vode. U 73% detektiranih aberacija radilo se o numeričkoj promjeni kromosoma, a najčešća je to bila trisomija 21 (69%). Preostalih 27% aberacija odnosi se na strukturne promjene kromosoma, od kojih je 54% nastalo kao posljedica svježe mutacije (de novo), dok su ostale bile obiteljskog podrijetla. U 23% strukturnih aberacija radilo se o nebalansiranoj promjeni. Stopa detekcije DS-a primjenom biokemijskog testa probira za DS u čitavom uzorku iznosila je 64% (14/22), a od 2000. godine, otkako se rabi trostruki test, iznosi 70% (7/10), uz 6,9% pozitivnih nalaza. Respektabilan broj utvr|đenih abnormalnih kariotipova u drugom tromjesečju trudnoće jasno upućuje na važnost primjene i invazivnih i neinvazivnih metoda prenatalne dijagnostike
The purpose of this paper was to present the organization of prenatal care in the city of Rijeka and to present the results obtained by noninvasive (biochemical screening for Down syndrome-DS) and invasive methods (amniocentesis-AC) for chromosomal aberration detection during the second trimester of pregnancies. A total of 1856 AC were performed from May 1986 until August 2004 and 10,057 pregnant women underwent prenatal biochemical screening for DS using double (MS-AFP and free β-hCG) or triple tests (MSAFP, free β-hCG and nE). The frequency of abnormal karyotypes in the pregnancies that underwent AC was 2,6%. The most common aberration was numerical (73%) with trisomy 21 in great numbers (69%). Structural anomaly was found in 27% of all obtained aberrations and 54% of them were de novo mutation. Unbalanced structural abnormalities were present in 23% of all of them. The detection rate for DS using non-invasive test was 64% (14/22), but from the year 2000 until now the detection rose to 70% (7/10), with the 6.9% screen positive rate. The respectable number of abnormal karyotypes identified in our work clearly demonstrated that non-invasive as well as invasive methods should be used in prenatal diagnostics during the second trimester.