Pseudoreticulocytosis in a Patient with Hemoglobin Köln due to Autofluorescent Erythrocytes Enumerated as Reticulocytes by the Cell-Dyn 4000

Abstract

Pseudoreticulocytosis in a 25-year-old female patient with hemoglobin Köln is reported. The abnormal hemoglobin, hemoglobin Köln (beta chain, Val98-->Met), had previously been confirmed in the patient at the age of 21 years, as well as in her mother, by polymerase chain reaction-based direct sequence analysis of the beta globin gene. The patient underwent splenectomy at the age of 22 years. On her admission to our hospital for treatment of an immunoglobulin A nephropathy, an analysis by an automated hematology analyzer, the Abbott Cell-Dyn 4000 (CD4000), reported a marked reticulocytosis. Staining by the Brecher method with new methylene blue indicated a moderate reticulocytosis (5.7%) of a lesser extent than that indicated by the CD4000 (51.1%). The frequencies of red blood cells (RBC) with Pappenheimer bodies (13.8%), Heinz bodies (32.7%), and Howell-Jolly bodies (0.3%) were increased. The CD4000 detects RBC with RNA fluorescently stained with CD4K530 as reticulocytes. Autofluorescence of RBC with hemoglobin Köln, as we demonstrated by flow cytometry and fluorescent microscopy, was considered to have caused the pseudoreticulocytosis on the fully automated reticulocyte enumeration by the CD4000.

Performance Evaluation of the ADVIA 2120 Hematology Analyzer: An International Multicenter Clinical Trial

“…The ADVIA 2120 system operates with a novel cyanidefree method of measuring hemoglobin. Interference of abnormal hemoglobins with results from automated cell counters has been reported in the literature [17]. We were concerned that abnormal hemoglobins, such as hemoglobin S, E or C, might give different measurements on the ADVIA 2120 system.…”

Determination of red cells, nucleic acid‐containing cells and platelets (RNP Determination) by a crossover analysis of emission DNA/RNA light

“…However, automated reticulocyte analysis has some major problems, such as inaccurate gating for red cells and intra-erythrocytic particles (Oyamatsu et al, 1989;Lofsness, Kohnke & Geier, 1994;Lacombe et al, 1999;Sato et al, 2004). Inaccurate gating of red cells is caused by giant platelets, platelet clumps, red cell fragments, abnormal white cells, white cell fragments and nucleated red cells, whereas intra-erythrocytic particles result from Howell-Jolly bodies, Pappenheimer bodies, Heinz bodies, basophilic stippling, hemoglobin H inclusions, plasmodium and Babesia (Pappas, Owens & Flick, 1992;Ghevaert et al, 1997;Riley et al, 2001).…”