Improving the differential diagnosis between myelodysplastic syndromes and reactive peripheral cytopenias by multiparametric flow cytometry: the role of B-cell precursors.
BACKGROUND
Immunophenotyping is a valuable ancillary technique for the differential diagnosis between myelodysplastic syndromes (MDS) with low bone marrow (BM) blast counts and a normal karyotype, and reactive peripheral (PB) cytopenias. Our aim was to search for the most important variables for this purpose. We also analyzed the age variation of BM B-cell precursors (BCP) and its differences in reactive and clonal cytopenias.


METHODS
Immunophenotypic analyzes were performed in BM of 54 patients with MDS (76% with BM blasts <5%) and 35 cases of reactive cytopenias. Healthy allogeneic BM transplantation donors (n = 41) were used as controls. We used a four-color panel of antibodies analyzing 9 granulocytic, 8 monocytic and 6 CD34(+) cell features.


RESULTS
Asynchronous shift to the left in maturing granulocytes and increase in CD16(+) monocytes were also found in reactive PB cytopenias, but the most important aberrancies in MDS were seen in myeloid CD34(+) cells. Decrease in BCP, that is a hallmark of MDS, could also be found in reactive cytopenias, especially in patients >55 years. % BM BCP could be calculated by the formula: (-7.97 × log age) + (4.24 × log % CD34 (+) cells) - (0.22 x nr. alterations CD34 (+) cells) + 0.577. Corrected R(2) = 0.467.


CONCLUSIONS
Analysis of myelomonocytic precursors and CD34(+) cells was satisfactory for the differential diagnosis between reactive PB cytopenias and MDS. The most specific alterations were found in CD34(+) cells. Comparison of the values obtained with those of normal age-matched controls is recommended.
The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1975931809154663.
Hematology and Hemotherapy Center, University of Campinas, Carlos Chagas Street, 480, 13083-878 Campinas, São Paulo, Brazil. suireis@unicamp.br.
Suiellen C
SC
Reis-Alves
Faculty of Medicine of Ribeirão Preto, University of São Paulo, Vila Monte Alegre, 14048-900, Ribeirão Preto, Sao Paulo, Brazil. ftraina@fmrp.usp.br.
Fabiola
F
Traina
Faculty of Medicine, University of Campinas, Tessália Vieira de Camargo Street 126, 13083-887, Campinas, São Paulo, Brazil. kmetze@fcm.unicamp.br.
Konradin
K
Metze
Hematology and Hemotherapy Center, University of Campinas, Carlos Chagas Street, 480, 13083-878 Campinas, São Paulo, Brazil. ilmetze@unicamp.br.|Faculty of Medicine, University of Campinas, Tessália Vieira de Camargo Street 126, 13083-887, Campinas, São Paulo, Brazil. ilmetze@unicamp.br.
Irene
I
Lorand-Metze
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D003937:Diagnosis, Differential; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping / Q000379:methods*; D007621:Karyotyping; D007970:Leukopenia / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology; D054448:Precursor Cells, B-Lymphoid / Q000276:immunology*; D011237:Predictive Value of Tests; D055815:Young Adult
D018952:Antigens, CD34; D015415:Biomarkers