Objective: To investigate the implications of erythroblasts periodic acid-Schiff (PAS) stain for myelodysplastic syndromes (MDS) dyserythropoiesis, diagnosis and differential diagnosis.
Methods: PAS stain of bone marrow (BM) erythroblasts in 406 MDS patients, 207 non-severe aplastic anemia (NSAA), 144 immune thrombocytopenic purpura (ITP), 67 megaloblastic anemia (MegA), 76 iron deficiency anemia (IDA), 50 paroxysmal nocturnal hemoglobinuria (PNH), and 50 acute erythroid leukemia (AEL) as well as some related laboratory parameters in MDS patients were analyzed retrospectively.
Results: PAS-positive detection rate was significantly higher in MDS (53.0%) than in NSAA (14.5%), ITP (27.1%) and PNH (16.0%), but was significantly lower in MDS than in AEL (84.0%) (all P = 0.000). There was no significant difference in PAS-positive detection between MDS and MegA (46.3%), or MDS and IDA (40.8%) (P = 0.310, 0.052, respectively). Erythroblasts PAS-positive rate (Median, M = 1%) and PAS-positive scores (M' = 2) was significantly lower in MDS than in AEL (M = 8%; M' = 17), and significantly higher than in NSAA (M = 0%; M' = 0), ITP (M = 0%; M' = 0), PNH (M = 0%; M' = 0), MegA (M = 0%; M' = 0), and IDA (M = 0%; M' = 0) (all P < 0.05). The cut-off value of PAS-positive rate and score for distinguishing MDS from the other groups except AEL were 0.5% and 0.5, with a sensitivity and specificity of 60.8% and 74.4%, respectively. For MDS patients, the percentage of BM erythroid cells was significantly higher in PAS-positive group than in PAS-negative group (P < 0.05), and so were megakaryocyte count, lymphocyte-like micromegakaryocytes count and percentage of micromegakaryocyte (P = 0.002, 0.000, 0.000, respectively). HGB, MCV, MCH and MCHC were significantly lower in PAS-positive group (all P < 0.05), and so was the neutrophil alkaling phosphatase (NALP) (P = 0.000). PAS-positive detection rate, positive rate and score were higher in MDS patients with abnormal karyotype than with normal karyotype, and were also higher in IPSS high/intermediate-risk 2 group than in low/intermidiate-risk 1 group.
Conclusion: The positive reaction of erythroblasts PAS stain is an indicator of dyserythropoiesis. It is helpful to the diagnosis of MDS patients.