Flow cytometric assessment of feto-maternal hemorrhage; a comparison with Betke-Kleihauer.
OBJECTIVE
Assessing the number of fetal cells in the maternal circulation quantifies the volume of feto-maternal hemorrhage, enhancing the ability to provide effective prevention of Rhesus (Rh) allommunization and appropriate fetal surveillance in cases of significant feto-maternal hemorrhage.


METHODS
Having developed a standard curve with maternal samples spiked with known volumes of fetal red blood cells, we used a flow cytometric method using fluorescent labeled antihemoglobin F to quantitate fetal cells in the maternal circulatory system in two groups of women undergoing chorionic villus sampling (CVS), by either biopsy forceps or cannula aspiration (n = 170 women). We compared these results with the gold standard, the Betke-Kleihauer test.


RESULTS
Our results show good correlation between the flow cytometric method and the traditional Betke-Kleihauer method for fetal red cell quantitation (r(2) = 0.99). Fetal red blood cells were identified in 10 women by the Betke-Kleihauer method, and in 26 women by flow cytometry. CVS was not associated with an increase in feto-maternal hemorrhage.


CONCLUSIONS
Flow cytometry was both more sensitive and more timely for the quantitation of feto-maternal hemorrhage than was Betke-Kleihauer.
Fernandes
Bernard J
BJ
Department of Laboratory Medicine, Mount Sinai Hospital, University of Toronto, Toronto, ON, Canada.
von Dadelszen
Peter
P
Fazal
Inez
I
Bansil
Nikki
N
Ryan
Greg
G
D015193:Chorionic Villi Sampling; D005260:Female; D005331:Fetomaternal Transfusion / Q000175:diagnosis*; D005434:Flow Cytometry; D006801:Humans; D011247:Pregnancy; D000509:alpha-Fetoproteins / Q000378:metabolism
D000509:alpha-Fetoproteins