Blood chimerism in a dizygotic dichorionic pregnancy.

Blood chimerism in twins is known to occur through the transfer of hematopoietic stem cells between the fetuses via a common placenta. We present a case of blood chimerism in a dizygotic dichorionic twin pregnancy. The female twin was delivered at 34 weeks of gestation, and the male twin was stillborn. Pathologic examination confirmed dichorionic diamniotic placentas. The karyotype of the female child was obtained using peripheral blood sample, and it revealed a mixture of 46,XX and 46,XY cells (chi 46,XY[13]/46,XX[7]). FISH analysis performed on the buccal cells by using CEP X/Y probe (Abbott Molecular Inc., USA) revealed 100% XX signals (nuc ish Xcen(DXZ1x2)[500]). Gross examination of the external genitalia and abdominal ultrasonography revealed no definitive abnormal findings in relation to sex differentiation. When XX/XY chimerism is present in blood lymphocytes, careful examination of external genitalia and reproductive organs and further studies are required to detect chimerism in non-hematopoetic tissues. This is a rare case of blood chimerism in dichorionic placentas, in contrast to those in monochorionic placentas.

Successful management of anti-Jra alloimmunization in pregnancy: a case report.

BACKGROUND: Hemolytic disease of the fetus/newborn due to Jr(a) immunization is very rare and considered to be mild, and only routine obstetrical care is recommended for pregnant women sensitized to the Jr(a) antigen. CASE REPORT: A 20-year-old nulliparous woman was referred to our hospital for perinatal management. Her indirect Coombs test was positive for anti-Jr(a) antibody (1:64). At 33 weeks' gestational age, we observed that fetal growth was mildly restricted and the peak systolic velocity of the fetal middle cerebral artery (PSV-MCA) was above the upper limit of the reference range (1.55 multiples of the median). Amniocentesis was also carried out and the DeltaOD450 value was in the lower mid-zone of the Liley curve. We continued to carefully observe the patient because we observed PSV-MCA values within 1.50-1.60 multiples of the median and no other findings of fetal anemia. She vaginally delivered a female infant weighing 2,136 g at 37 weeks' gestational age. The infant received treatment with both iron and recombinant erythropoietin without developing hyperbilirubinemia and blood transfusion. CONCLUSION: PSV-MCA should be monitored for the detection of fetal anemia, even in pregnant women sensitized to some antigens for which only routine obstetrical care is recommended.

Rh alloimmunization and term delivery.

Nowadays management of severe Rh alloimmunization consists of serial determination of middle cerebral artery peak systolic velocity, amniocentesis, cordocentesis, and in many instances intrauterine transfusion. We present a case of severe Rh alloimmunization who, for the first time in Iran, was delivered at term after several intrauterine transfusions.

Management of Kell isoimmunization--evaluation of a Doppler-guided approach.

OBJECTIVE: To assess the role of peak systolic velocity in the middle cerebral artery (MCA-PSV) in the management of pregnancies complicated by Kell isoimmunization. METHODS: Sixteen fetuses were monitored by conventional protocol (Group 1) and eight fetuses by an MCA-PSV-guided protocol (Group 2). The conventional protocol included a weekly ultrasound evaluation and measurement of maternal anti-Kell titers every 4-6 weeks. In Group 2 Doppler assessment of the MCA-PSV was performed at intervals of 4 to 7 days and MCA-PSV>1.5 multiples of the median (MoM) was considered as an indication for fetal blood sampling (FBS). RESULTS: No parameter emerged as a reliable predictor of isoimmunization severity in Group 1. In Group 2, no FBS was necessary in one case since the MCA-PSV values obtained during the follow-up were <1.29 MoM. In two cases the first FBS was already indicated after 1 week of follow-up, but five other fetuses were followed for 3-9 weeks before FBS was indicated. All fetuses with MCA-PSV>1.5 MoM prior to intrauterine transfusion (IUT) had severe fetal anemia on FBS. In fetuses with severe anemia on the first FBS, the MCA-PSV values 7 days before the first FBS were <1.29 MoM (four cases), between 1.29 and 1.5 MoM (two cases) and >1.55 MoM (one case). CONCLUSIONS: In the management of Kell isoimmunization invasive procedures may be avoided by implementing MCA-PSV measurements. Delineation of appropriate intervals between reassessments, the reliability of MCA-PSV following repeated IUTs, and cut-off values for FBS await further study.

Intra-amniotic bleeding and fetal echogenic bowel.

OBJECTIVE: To assess the relationship between intra-amniotic bleeding and fetal echogenic bowel. METHODS: Comprehensive fetal ultrasound examinations were done before and 12 hours after fetal transfusions. Follow-up ultrasound examinations were done weekly in 28 fetuses with intra-amniotic bleeding. Hyperechogenic bowel was diagnosed when the echogenicity of fetal bowel was similar to that of bone. Postpuncture bleeding was identified when a stream of echogenic material from the cord into the amniotic space was seen, lasting at least 60 seconds. RESULTS: None of the fetuses had echogenic bowel before initial transfusions. Intra-amniotic bleeding was followed by bowel echogenicity in seven of 28 fetuses within the first 12 hours after bleeding episodes. Echogenic bowel remained in five fetuses 2 weeks after the bleeding episodes. In three fetuses, echogenic bowel was still seen 4 weeks later. CONCLUSION: Intra-amniotic bleeding can lead to echogenic bowel.

Ultrasonographic fetal spleen measurements in red blood cell-alloimmunized pregnancies.

OBJECTIVES: This study was performed to evaluate the possible relationship between fetal spleen size and fetal hemoglobin levels and to assess the predictive value of ultrasonographically measured fetal spleen size as an estimate of the severity of fetal hemolytic anemia. STUDY DESIGN: Before 85 consecutive fetal blood samples in 28 red blood cell-alloimmunized pregnancies ultrasonographic fetal spleen measurements were performed. Results were compared with our own longitudinally derived reference ranges and were correlated with fetal hemoglobin deficit. RESULTS: A significant positive correlation was found between spleen perimeter and fetal hemoglobin deficit. The ultrasonographic finding of splenomegaly correctly predicted severe fetal anemia (hemoglobin deficit > 5 SD from normal mean) in 44 of 47 cases, a positive predictive value of 94%. At first transfusion all fetuses showing splenomegaly were severely anemic. CONCLUSION: Fetal spleen measurements may be a useful adjunct to ultrasonographic evaluation in the management of severe red blood cell-alloimmunized pregnancies.