In this issue of the ICCS eNewsletter, we have articles about News from Q&S committee, Flow Cytometry Assay to Detect Fetal Red Blood Cells, Duraclone Screening Tube, and one CSI case.
The Quality & Standards (Q&S) committee continues with their efforts to provide practical guidance to the various challenges in flow cytometry laboratories. Andrea Illingworth provides an update on the latest modules of Q&S committee (see https://www.cytometry.org/web/quality.php). The topics include "Instrument Installation, Operational, and Performance Qualification for BD FACS Canto II", "Expression of CD5 on Normal Hematolymphoid Cells", "Qualification of a 10C 3L Navios Flow Cytometer for Clinical Laboratory Testing", and the future module of "Tissue Disaggregation Methods for Flow Cytometric Immunophenotyping". Please also feel free to contact the committee with any ideas for future modules at email@example.com.
Does your laboratory provide quantitative-flow cytometry anti-Hemoglobin F assay to detect fetal red blood cells (FRBC)? The accurate determination of the quantity of FRBC in maternal circulation is imperative to prescribe the right amount of RhIG to prevent Rh D alloimmunization. There are three methodologies to detect FRBC: qualitative assay (Rosette Anti-D assay), semi-quantitative assay [Kleihauer-Betke (KB), cytochemical slide test)], and quantitative assay (flow cytometry anti-Hemoglobin F assay). The article by Bruce Greig on "Using Flow Cytometry to Detect Fetal Red Blood Cells in Maternal Circulation" describes the principles, limitation and advantage of these assays, and presents some relevent CAP survey results. The flow cytometric anti-HbF assay demonstrates much higher precision and accuracy compared to the widely used KB stain and is therefore considered the gold standard for the quantitation of FRBC's. Read this article to gather more facts about the flow assay.
For anyone involved in set-up a new flow cytometry assay using dried antibody reagents to screen hematological malignancies, you will be interested in reading the article by Rodolfo Patussi Correia, Laiz Cameirao Bento and Amr Rajab on "A ten-color tube with dried antibody reagents for the screening of hematological malignancies - Duraclone Screening Tube". This technology allows ease of storage, rapid training of the technical staff, reduction in the instability of tandem fluorochromes in liquid cocktails, elimination of pipetting errors, and reduction in the loss of liquid antibodies due to expiration date. In order to improve the technical flow cytometry workflow, they customized the 10-color screening tube (DST) as a dry antibodies cocktail using the Beckman Coulter dry coating technology (named Duraclone). This article describes their DST configuration, assay performance, analytical results including its applicability (detecting ~ 60% of hematological malignancies), and cost reduction figures. They conclude that the dry reagent DST is an efficient solution for screening hematological malignancies with improved quality, productivity, standardization, and sustainability.
Have you been challenged to diagnose primary effusion lymphoma (PEL) by flow cytometry? This newsletter presents one CSI case that was contributed by Kirill Lyapichev and Sanam Loghavi to test your analytical skills. PEL is associated with a proliferation of large B-cells which are positive for HHV8 and CD30 (in the majority of cases) with plasmacytic differentiation and diminished to absent B-cell marker expression. As a further complicating feature, PEL may have T-cell antigen expression, as in this case with partial CD7 expression. Awareness of this diagnostic pitfall is essential to avoid the misdiagnosis as a T-cell lymphoma. Can you decide the lineage of the abnormal population? What differential diagnosis is suggested? Enjoy this test of your diagnostic skills. Please also consider to submit your interesting case to be shared with your colleagues.
Weina Chen, MD, PhD