This study was purposed to investigate the megakaryocytic dysplasia and leukemia-associated phenotypes (LAP) of acute myeloid leukemia (AML) in the elderly. The megakaryocytic dysplasia, lineage infidelity, asynchronous antigen expression, total WBC count, and karyotypes were observed in the 147 none M(3)-AML patients. Logistic regression were used to analyzed the difference between the elderly (age > or = 60) and the control. The results showed that out of the total 147 patients (66 elderly patients, and 81 younger patients) 124 patients accepted induction chemotherapy, in which 70 cases achieved complete remission (elderly 18, younger 52, p = 0.008); megakaryocytic dysplasia was found in 32 patients (21.8%); CD33 and CD19/CD7 (lineage infidelity) was co-expressed in 55 patients (37.4%), CD34 and CD11b (asynchronous antigen expression) was co-expressed in 65 patients (44.2%); white blood cell count > 25 x 10(9)/L was found in 52 patients (35.4%). By the Logistic regression, compared with the control, in the elderly patients there was difference in the megakaryocytic dysplasia, and the co-expression of CD33/CD19/CD7 and CD34/CD11b (OR = 4.315, 2.761, 0.397; p = 0.001, 0.006, 0.020), but there was no difference in the total WBC count and karyotypes (OR = 0.802, 1.096; p = 0.646, 0.813). It is concluded that the incidence of megakaryocytic dysplasia, such as lineage infidelity, and asynchronous antigen expression, in elderly patients is higher than that in younger patients.
Adolescent ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Female ; Humans ; Immunophenotyping ; Leukemia, Myeloid, Acute ; immunology ; pathology ; Logistic Models ; Male ; Megakaryocytes ; pathology ; Middle Aged ; Prognosis ; Young Adult

OBJECTIVEBone marrow megakaryocytes overly proliferate and abnormally develop among patients with idiopathic thrombocytopenic purpura (ITP). Previous studies showed that it resulted from the abnormal immune function of the body. But the changes in megakaryocytes, especially in micromegakaryocytes in this disease are unclear. The present study was designed to explore the growth and development status of megakaryocytes and the significance of changes in micromegakaryocytes in pediatric cases.

METHODSRoutine bone marrow smears assay and enzyme labeling for micromegakaryocytes with CD41 monoclonal antibody (McAb) were performed in 46 children with ITP. The level of platelet-associated immunoglobulin (PA-Ig) was measured with ELISA.

RESULTSAmong 46 children, 36 had acute ITP (AITP)and 10 chronic ITP (CITP). The number of megakaryocytes increased or was normal in 45 patients, but decreased only in 1 case of CITP. The positive rate of micromegakaryocytes and type I micromegakaryocytes was 98% (45/46) and 35% (16/46), respectively. The positive rate of type I micromegakaryocytes was higher in CITP (50%) cases than that in AITP (31%) cases, but the median of the other three types of micromegakaryocytes in CITP cases (159) was lower than that in the AITP cases (336). There was no relationship between the numbre of all types of megakaryocytes and the level of PA-Ig.

CONCLUSIONMajority of patients with ITP showed an increase in micromegakaryocytes, especially in type II, III and IV. The immune disturbance might not be the only reason for ITP. The abnormality of quality of megakaryocytes might be one of the potential causes for thrombocytopenia in some cases of ITP, especially in those of CITP. The appearance and the number of type I micromegakaryocytes might reflect the prognosis of cases of ITP.

Adolescent ; Blood Platelets ; immunology ; Cell Count ; Child ; Child, Preschool ; Female ; Humans ; Immunoglobulins ; analysis ; Infant ; Male ; Megakaryocytes ; immunology ; pathology ; Platelet Membrane Glycoprotein IIb ; analysis ; Purpura, Thrombocytopenic, Idiopathic ; blood ; immunology ; pathology

OBJECTIVETo study the roles of platelet (PLT) and its regulating factors, megakaryocyte, thrombopoietin (TPO) and transforming growth factor beta1 (TGF-beta1), in immune vasculitis in young rabbits.

METHODSAn experimental model of Kawasaki disease (KD) of weanling rabbits was reproduced by bovine serum. PLT count, total number and differentiating count of megakaryocyte, and serum TPO and TGF-beta1 levels were measured 0, 4, 8, 12, 16, 20, 24 and 28 days after KD induction. Pathological analysis of coronary artery, liver, spleen, kidney and brain was performed 17 and 28 days after KD induction.

RESULTSIn the KD group, PLT count, the total number of megakaryocyte, and the middle board megakaryocyte percentage increased 12, 16, 20, 24 and 28 days; serum TPO level increased 8, 12, 16, 20, 24 and 28 days; serum TGF-beta1 level increased 16, 20, 24 and 28 days after KD induction compared with those in the normal control group (p<0.05). The pathological examinations of coronary artery, liver, spleen, kidney and brain showed severe inflammatory injuries of tiny arteries and small/medium-sized arteries 17 and 28 days after KD induction, respectively in the KD group. The aortas were showed as mild inflammatory injuries.

CONCLUSIONSPLT, megakaryocyte, TPO and TGF-beta1 participate in the pathogenesis of KD, and they may play an important role in the injuries of immune vasculitis. This suggests that they may serve as markers for the assessment of severity in KD.

Animals ; Blood Platelets ; physiology ; Disease Models, Animal ; Humans ; Megakaryocytes ; physiology ; Mucocutaneous Lymph Node Syndrome ; etiology ; Rabbits ; Thrombopoietin ; physiology ; Transforming Growth Factor beta1 ; physiology ; Vasculitis ; etiology ; immunology ; pathology

BACKGROUND: In patients with isolated thrombocytopenia, but without significant dysplasia, diagnosis of idiopathic thrombocytopenic purpura (ITP) rather than myelodysplastic syndrome (MDS) may be taken into account. It is important to make an accurate diagnosis because different treatments are used for ITP and MDS. The purpose of this study was to investigate the clinical and hematologic features of patients who were initially diagnosed as ITP but had cytogenetic abnormalities. METHODS: We retrospectively reviewed cytogenetic studies of 100 patients who were diagnosed as ITP from 2004 to 2009 at Mokdong Hospital of Ewha Womans University based on clinical features and hematologic studies. Bone marrow pathology was re-evaluated based on 2008 WHO classification. Cytogenetic analysis was performed by 24-48 hr culture of bone marrow aspirates without using mitogens and 20 metaphases were analyzed. RESULTS: Of the 100 patients diagnosed as ITP initially, three patients (3%) had cytogenetic abnormalities. They had no thrombocytopenia-related symptoms and thrombocytopenia was found accidentally. The numbers of megakaryocytes in bone marrow were increased and dysplasia was not found in megakaryocyte, erythroid, and myeloid cell lineages. The proportion of blasts was within normal limits. Clonal chromosomal abnormalities found were der(1;7)(q10;p10), add(9)(q12), or t(7;11)(p22;q12). Presumptive diagnosis of MDS or diagnosis of idiopathic cytopenia of undetermined significance (ICUS) was made according to 2008 WHO classification. During the follow up, disease progression was not found. CONCLUSIONS: In patients with suspected ITP, cytogenetic analysis should be done. If specific clonal chromosomal abnormality is found, presumptive diagnosis of MDS has to be considered and close follow up is needed.
Adult ; Bone Marrow Cells/cytology ; Cell Lineage ; Chromosome Aberrations ; Diagnosis, Differential ; Female ; Humans ; Male ; Megakaryocytes/immunology/pathology ; Middle Aged ; Myelodysplastic Syndromes/*diagnosis/genetics/pathology ; Purpura, Thrombocytopenic, Idiopathic/*diagnosis/genetics/pathology ; Retrospective Studies