The prevalence of an elevated F cell population in a maternal and gynaecology cohort

Abstract

SUMMARY Objectives This study aimed to determine F cell prevalence in a cohort of maternal and gynaecology specimens using QuikQuant anti‐HbF flow cytometry (FC) kit and to investigate if the presence of maternal F cells can lead to fetomaternal haemorrhage (FMH) overestimation. Background The gold standard to estimate FMH is the Kleihauer–Betke test (KBT). The KBT has proved to be insufficiently sensitive to detect low numbers of circulating fetal cells due to the presence of maternal F cells. At present, the prevalence of false positive KBT results due to raised maternal F cell population, defined as >5%, is poorly characterised. Methods A total of 120 specimens were tested for the presence of F cells and fetal cells by KBT and anti‐HbF FC. The results calculated were compared to determine FMH overestimation. Results Of our cohort, 32% showed an elevated F cell population, of which 69% (27 of 39) were clinically significant according to KBT (>2 mL FMH). The mean FMH volumes by KBT and anti‐HbF FC were 3·90 mL (0·20–35·40 mL) and 4·09 mL (0·20–9·70 mL), respectively. Conclusion The study highlighted that an elevated F cell level could be found in the cohort tested, with an F cell level of >10% causing significant FMH overestimation by KBT.

Prenatal diagnosis of fetomaternal hemorrhage by a novel hydrogel fluoroimmunoassay that accurately quantifies fetal haemoglobin

“…Inability to distinguish between HbF and F cells is a common source of false-positive results in K-B tests (Flynn et al, 2022). F cells refer to normal RBCs (Alter, 1984;Fabry et al, 2001;Corcoran et al, 2014) that contain a small amount of HbF (1%-2% in adults) (Cormack et al, 2019). Nonetheless, certain inherited or acquired Frontiers in Bioengineering and Biotechnology frontiersin.org haemoglobin disorders, such as sickle cell anaemia and -thalassemia, result in a substantial increase in HbF levels.…”

A novel enzyme-linked immunostaining technique based on silk membrane for the prenatal detection of fetomaternal haemorrhage

“…The essence of detecting FMH is the quantitative detection of fetal red blood cells in the peripheral blood of pregnant women ( Troia et al, 2019 ). Prenatal detection of maternal hemorrhage is the foundation for preventing newborn hemolytic disease and administering immunoglobulin therapy ( Christino Luiz et al, 2019 ; Cormack et al, 2019 ; Flynn et al, 2022 ).…”