[Anti-K antibodies in pregnant women and genotyping of K antigen in foetuses]. / Przeciwciala anty-K u kobiet ciezarnych oraz badania genu kodujacego antygen K u plodów.

AIM: 1) We have presented our experiment conducted to detect anti-K antibodies from the Kell-system in pregnant women and their connection with potential destruction of foetal red cells, which may result in haemolytic disease of the foetus and the newborn (HDFN). 2) We have also indicated serological and molecular methods important for a proper diagnosis. MATERIAL AND METHODS: 27 women with anti-K. Serological diagnosis of K antigen in fathers and children. KEL1 gene examination in foetuses from DNA isolated from foetal cells contained in amniotic fluid, using discrimination of alleles--real-time PCR method. RESULTS: Anti-K were detected in most women after blood transfusion, the fathers were usually K negative. Foetomaternal incompatibility was found in 6 out of 27 women. Haemolytic disease was observed in 5 cases: 3-severe, 1-fatal, 1-mild. Foetal genotyping allowed us to avoid cordocentesis in two pregnant women, it appeared that both foetuses have not received KEL1 gene from heterozygous (Kk) fathers--in the previous pregnancies the children had died because of HDFN. CONCLUSIONS: 1) In every pregnant woman with anti-K, the K antigen should be examined in the father. 2) In every K+ father the phenotype should be evaluated and if he is heterozygote (Kk), the fetal KEL1 gene must be examined, to avoid unnecessary cordocentesis. 3) If KEL1 gene is not detected in the foetus, HDFN will not occur. 4/Foetal KEL1 genotyping may be performed in all mothers with anti-K and heterozygous father in our Department, after providing the material from the amniocethesis.

[Fetal D gene in maternal plasma should be examined in all immunized Rh(-) pregnant women to avoid invasive procedures]. / Dla unikniecia stosowania inwazyjnych metod diagnostycznych nalezy badac obecnosc genu RhD plodu w osoczu zimmunizowanych ciezarnych Rh ujemnych.

UNLABELLED: We have recently developed and published a noninvasive determination of fetal RhD status by examination of cell-free DNA in maternal plasma. The predictive value of the procedure of fetal testing, already published by us, was 99,6%. AIM: To assess the necessity of RhD fetal testing in immunized Rh(-) mothers with Rh(+) partners. MATERIAL: Rh(-) mothers with anti-D antibodies, their partners and children. METHODS: Molecular: RHD gene examination by real-time polymerase chain reaction; analysis of control genes present in the father but not in the mother. Serological: titre of anti-D antibodies, Rh phenotypes. RESULTS: Among 53 Rh(+) partners of immunized Rh(-) pregnant women, 56,6% were homozygous and 43,6%--heterozygous. The latter ones might have had either Rh(+) or Rh(-) children; in fact, in 52,2% of fetuses the D gene was not detected. Among fetuses of homozygous fathers (based on their phenotypes) 2 fetuses, to our surprise, occured to be Rh(-); however the subsequent genotyping showed that both fathers were heterozygous. The titres of anti-D in both groups of mothers with Rh(-) and Rh(+) fetuses were very similar. CONCLUSIONS: The examination of fetal D gene by noninvasive method should be performed in each alloimmunised Rh(-) mother if her partner is Rh(+). The prediction of RhD fetal status based on the fathers phenotype can be misleading, thus may result in unnecessary invasive method.