Background: Myelodysplastic syndromes (MDSs) are a heterogeneous group of bone marrow disorders. Morphology may be difficult to evaluate in some patients, either due to hypocellularity or fibrosis of bone marrow.
Objective: To define immunophenotypic pattern in MDS patients, quantify and score complex flow cytometric abnormalities, and to correlate flow cytometry scores with conventional and established parameters used in MDS diagnosis.
Methods: Using flow cytometry, we studied 40 bone marrow specimens 30 patients with MDS and 10 cytopenic patients with non-clonal hematologic disorders as control group. A panel of monoclonal antibodies including: CD45, CD13, CD33, CD34, CD7, CD11b, CD16, CD56 and HLA-DR were used. Immunophenotyping using 2 gates were done: Forward (FSC) and right angle light scatter SSC and a second gate were done on the basis of CD45 staining and SSC to confirm identification of the selected cells. These combinations of Moab were used to measure the degree of maturation of their corresponding antigen by expressing their intensity.
Results: For MDS diagnosis, FCM had a sensitivity and specificity of 86.7% and 80% with score 1.5:9, 80% and 100% with score 3.5:9, 53.3% and 100% with score 5:9 and 30% and 100% with score 6.5:9 respectively, and a significant positive correlation between IPSS and FCM score.
Conclusion: This study defines immunophenotypic pattern in MDS patients and allow for a simple numerical display of results as score which is positively correlated with IPSS.