Evaluation of a Flow Cytometry Method for Identifying and Quantifying Fetal Red Blood Cells in Maternal Blood

Sammanfattning: Hemoglobin is an oxygen binding protein in erythrocytes. Hemoglobin is composed of four polypeptide chains. During the fetal stage the type of hemoglobin called fetal hemoglobin (HbF) dominates. After birth HbF is replaced by adult hemoglobin (HbA). HbF persists in concentrations less than 1%. Elevated concentration of HbF in adults exists in different conditions, Talassemi for example. When the uterus is damaged and the fetus doesn’t feel well its blood can pass the placenta barrier and enter the blood stream of the mother. A venous blood sample from the mother is analyzed to determine the status of the fetus. Laboratory Medicine Västernorrland already has two methods for analyzing HbF, one routine and one on call. The routine method needed to be replaced and the possibility to use flow cytometry was investigated. In this study, results from flow cytometry using Fetal Cell Count™ kit was compared to the results from the presently used methods, Kleihauer-Betke and HPLC. Cord blood was diluted with venous blood from an adult with the same blood group in various concentrations. A number of tests were performed and showed a fairly good correlation between the different methods. However more tests will be necessary to draw any clear conclusion.