CLINICAL USEFULNESS OF FLOW-CYTOMETRY IN DETECTION AND QUANTIFICATIONOF FETOMATERNAL HEMORRHAGE

Objective: To compare the technique of immunofluorescence flow cytomet ry against traditional Kleihauer testing with respect to the sensitivi ty and specificity of clinical detection of fetomaternal hemorrhage. M ethods: Blood samples from D-negative unsensitized postpartum women we re analyzed by flow cytometry (customized, directly conjugated monoclo nal anti-D) and Kleihauer testing using commercial kits as well as a m anual technique. Results: Both flow cytometry and manual Kleihauer tes ts performed well in vitro against known standards, giving similar res ults with detectable fetal cells in the range of 2-10%. Correlation of in vivo results obtained by flow cytometry and either Kleihauer metho d was poor. The percentage of fetal red cells detected by flow cytomet ry was approximately twice that of the manual Kleihauer. Commercial Kl eihauer testing proved unreliable in the in vivo setting. Conclusions: Flow cytometry offers a reliable alternative to traditional Kleihauer testing for detecting fetomaternal hemorrhage and may, with standardi zed methodology, help optimize immunoprophylaxis against erythroblasto sis fetalis.