[Is a non-invasive management allowed for maternofetal alloimmune thrombocytopenia? Experience over a 10-year period]. / Peut-on prendre en charge l'allo-immunisation plaquettaire foetomaternelle de manière non invasive? Expérience sur dix ans.

OBJECTIVES: Our purpose was to study a non-invasive management of fetomaternal alloimmune thrombocytopenia (FMAIT). PATIENTS AND METHODS: Between 1996 and 2005, 18 women were treated. The population was divided into 2 groups: patients with a history of intracranial haemorrhage (ICH) in the older sibling received weekly intravenous immunoglobulin (IVIG) therapy to the mother (1 g/kg per week) without initial cordocentesis whereas patients with a history of neonatal thrombocytopenia did not undergo any treatment. RESULTS: All pregnancies with a previous FMAIT were monitored with serial ultrasound scans without cordecentesis. 15 patients had HPA-1, 2 HPA-3 and 1 HPA-5 immunizations. Weekly intravenous immunoglobulin therapy was administered in 5 patients with a history of ICH in the older sibling. Two of these delivered thrombocytopenic children; one had a platelet count < 50 x 10(9)/l. For the 13 women (one twin) who had a sibling with neonatal thrombocytopenia, 11/14 newborns had a platelet count < 50 x 10(9)/l. Predelivery fetal blood sampling were performed in 8/18 pregnancies. The neonatal periods of the 19 children were uncomplicated and no ICHs were observed. DISCUSSION AND CONCLUSION: Our results suggest that a non-invasive strategy avoiding serial cordocentesis may be an effective therapy in patients who are at risk of fetal and neonatal alloimmune thrombocytopenia.

[Evaluation of conventional hemi nested PCR analysis for fetal RHD determination in maternal plasma]. / Evaluation de la détermination du statut Rhésus-D foetal sur plasma maternel par la technique d'hemi-nested PCR.

AIMS: The aim of our study was to evaluate the possibility of identifying the fetal RhD status in maternal plasma using conventional hemi nested PCR analysis. SUBJECTS AND METHODS: After informed written consent, 20 mL of peripheral blood were collected in 99 D-negative pregnant women either at an amniocentesis for prenatal diagnosis or at a prenatal checkup. Fetal DNA extracted from 400 microL of maternal plasma was analyzed by two different operators with a hemi-nested PCR extending an area of the RhD gene exon 10. The results were compared to the fetal RhD status obtained by PCR amniotic fluid analysis or blood analysis of newborns after delivery. The influence of mother's and baby's phenotype were also studied. RESULTS: Among the 99 D-negative pregnant women, all Caucasian, 47 were in their second trimester and 52 in their third trimester (mean: 27.20 weeks of gestation +/-8.25). Sixty-nine fetuses were D-positive and thirty D-negative. The sensitivity and specificity of our technique were respectively 100% and 86.7% and 15% of discordant results were observed between the two operators. Four false positives were observed. According to maternal phenotype, a fetal unexpressed RHD gene was suspected in only one case because of a particular fetal phenotype (ddCcEe). CONCLUSION: A conventional hemi nested PCR analysis of maternal plasma could be used for accurate fetal RhD status. However this procedure is difficult to apply for routine analysis because of the importance of anti-contamination measures required to obtain good results. Real time quantitative PCR analysis on fetal DNA is more suitable. Whatever the operating procedure used, polymorphism of RhD gene may follow in either false negative from presence of rearranged gene or false positive from occasional presence of a non functional RHD gene.

Anti-TJa alloimmunization (anti-PP1Pk): two consecutive pregnancies of an anti-TJa-carrying patient.

Anti-TJa alloimmunization is an extremely rare condition which can cause miscarriages during the first and second terms of pregnancy. At 20-year-old female patient, an anti-TJa carrier, was given plasma transfusions in the course of her first two pregnancies. The cordocentesis, which was the main follow-up test during the first pregnancy, could not be carried out during the second pregnancy due to the presence of a huge subchorionic hematoma. Both pregnancies were characterized by fetal growth retardation, which was particularly considerable in one. Due to chronic fetal distress, both infants were delivered prematurely by cesarean section. The immunohematological data concerning anti-TJa alloimmunization and the different palliative treatments available to date are reviewed.