Calreticulin mRNA expression and clinicopathological characteristics in acute myeloid leukemia.

Calreticulin, encoded by CALR, is a multifunctional protein with roles in calcium homeostasis and chaperoning molecular processes. This study aimed to evaluate calreticulin mRNA expression levels in acute myeloid leukemia (AML) compared with other hematologic malignancies, and to investigate the clinicopathological characteristics associated with expression in AML patients. The study group included 43 patients diagnosed with AML, 57 with other hematologic malignancies, and 21 benign hematologic conditions.

KMT2A (MLL)-MLLT1 rearrangement in blastic plasmacytoid dendritic cell neoplasm.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy characterized by CD4 and CD56 coexpression without apparent lineage commitment. The molecular pathogenesis of BPDCN has been studied in only a limited number of cases, and specific chromosomal aberrations are lacking thus far. KMT2A (MLL) rearrangements are observed in various types of pediatric and adult leukemia, but only one adult case report has so far showed KMT2A (MLL)-MLLT1 gene rearrangements in BPDCN.

Clinical usefulness of bronchoalveolar lavage cellular analysis and lymphocyte subsets in diffuse interstitial lung diseases.

Background: Diffuse interstitial lung diseases (DILDs) form a part of a heterogeneous group of respiratory diseases. Bronchoalveolar lavage (BAL) analysis has been used for differential diagnosis of DILDs, but their clinical usefulness is controversial. The aim of this study was to investigate the clinical usefulness of BAL cellular analysis with lymphocyte subsets for the differential diagnosis of DILDs.

Submicroscopic deletions of immunoglobulin heavy chain gene (IGH) in precursor B lymphoblastic leukemia with IGH rearrangements.

Translocations leading to fusions between the immunoglobulin heavy chain gene (IGH) and various partner genes have been reported in B-cell precursor acute lymphoblastic leukemia (B-ALL). However, submicroscopic deletions within IGH in B-ALL have not been rigorously assessed. In this study, we investigated characteristics of IGH submicroscopic deletions, by FISH, in B-ALL with IGH rearrangements.

Assessment of therapeutic drug monitoring of vancomycin in elderly patients according to new guidelines.

Background: Concerns regarding increasing microbial resistance to vancomycin have resulted in recommendations for a higher trough serum vancomycin concentration. This study aimed to assess the dosage guidelines targeting vancomycin trough concentrations of 15-20 mg/L.

Methods: About 216 adult patients (age, >60 yr) were treated with intravenous vancomycin.

Single nucleotide polymorphism array-based karyotyping in acute myeloid leukemia or myelodysplastic syndrome with trisomy 8 as the sole chromosomal abnormality.

The clinical heterogeneity of patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) with trisomy 8 as the sole abnormality may result from cytogenetically undetectable genetic changes. The purpose of this study was to identify hidden genomic aberrations not detected by metaphase cytogenetics (MC) using high-resolution single nucleotide polymorphism array (SNP-A)-based karyotyping in AML/MDS patients with a sole trisomy 8. The study group included 8 patients (3 AML and 5 MDS) and array-based karyotyping was done using whole-genome SNP-A (SNP 6.

Additional genomic aberrations identified by single nucleotide polymorphism array-based karyotyping in an acute myeloid leukemia case with isolated del(20q) abnormality.

Prognosis is known to be better in cases with isolated chromosomal abnormalities than in those with complex karyotypes. Accordingly, del(20q) as an isolated abnormality must be distinguished from cases in which it is associated with other chromosomal rearrangements for a better stratification of prognosis. We report a case of an isolated del(20q) abnormality with additional genomic aberrations identified using whole-genome single nucleotide polymorphism array (SNP-A)-based karyotyping.

Ring chromosome 5 in acute myeloid leukemia defined by whole-genome single nucleotide polymorphism array.

Chromosomes forming a corresponding ring cannot be clearly defined by conventional cytogenetics or FISH. Karyotypic analyses using whole-genome single nucleotide polymorphism arrays (SNP-A) may result in the identification of previously cryptic lesions and allow for more precise definition of breakpoints. We describe a case of AML with metaphase cells bearing -5, del(11)(q22), and +r.

Single nucleotide polymorphism array-based karyotyping shows sequential genomic changes from monosomy to copy-neutral loss of heterozygosity of chromosome 7 and 20q deletion within a balanced translocation t(14;20) in AML.

Single nucleotide polymorphism array (SNP-A)-based karyotyping can identify copy-neutral loss of heterozygosity (CN-LOH) as well as cryptic lesions not detected by metaphase cytogenetics. We report serial genetic studies on a patient diagnosed with chronic myelomonocytic leukemia who progressed to acute leukemia. Monosomy 7 was predominantly found at diagnosis, but clones changed to CN-LOH of chromosome 7 with disease progression.

Clinical characteristics of hemophagocytic lymphohistiocytosis related to Kawasaki disease.

It is difficult to predict the prognosis or clinical course of secondary hemophagocytic lymphohistiocytosis (HLH) due to the various underlying causes. The authors analyzed the clinical and laboratory findings and outcomes in patients with HLH who had initially been diagnosed with Kawasaki disease (KD), and evaluated the clinical significance of each factor. Among the 21 patients with HLH, 5 had initially been diagnosed with KD and 16 had other etiologies.

[Variant Philadelphia chromosome identified by interphase fluorescence in situ hybridization (FISH) without evidence on G-banded karyotyping and metaphase FISH].

A variant Philadelphia chromosome (Ph) is generated from translocation of one or more partner chromosomes in addition to chromosomes 9 and 22. We have described the cases of 2 patients bearing variant Ph detected by interphase FISH but not detected by G-banded karyotyping and metaphase FISH. FISH was performed using BCR/ABL dual color dual fusion translocation probes (Abbott Molecular, USA).

Clinical utility of FISH analysis in addition to G-banded karyotype in hematologic malignancies and proposal of a practical approach.

Background: Fluorescence in situ hybridization (FISH) analysis can provide important information in the management of patients with hematologic malignancies. However, FISH performed in addition to G-banded karyotype can be labor-intensive and expensive. The aim of this study was to evaluate whether FISH gives additional information in the setting of adequate conventional cytogenetics in cases of hematologic malignancies.

[Myelodysplastic syndrome mimicking idiopathic thrombocytopenic purpura].

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.

Immunophenotypic features of granulocytes, monocytes, and blasts in myelodysplastic syndromes.

Background: Despite the diagnostic utility of immunophenotyping for myelodysplastic syndromes (MDS), it has not been widely performed, and reports on this are absent in Korea. We aimed to evaluate the immunophenotypic features of non-blastic granulocytes, monocytes, and blasts in patients with MDS and non-clonal disorders using routine flow cytometry (FCM). Moreover, we evaluated the phenotypic abnormalities of mature cells in leukemic patients.

Hemoglobin Yamagata: hemoglobin variant detected by HbA1c test.

Hemoglobin (Hb) Yamagata is a rare Hb variant, which has been reported only twice-one case each in Japan and Korea. This variant arises from a Lys --> Asn substitution due to a mutation of AAA to AAC or AAT at codon 133 of the beta-globin gene. This study reports the third case of a patient detected with Hb Yamagata [HBB: c.

Characteristics of acute myeloid leukemia without HLA-DR expression.

Background: HLA-DR negativity is known to be useful for distinguishing acute promyelocytic leukemia (APL) from other subtypes of AML, but non-APL cases without HLA-DR antigen expression have been reported. The purpose of this study was to evaluate and compare the characteristics of APL, HLA-DR negative non-APL, and HLA-DR positive non-APL cases.

Methods: A total of 114 cases of AML admitted at Ewha Womans University, Mokdong Hospital between March 1997 and June 2006 were included in this study.

A case of CD45-, CD19- precursor B cell acute lymphoblastic leukemia with an atypical morphology.

The differential diagnosis of acute lymphoblastic leukemia (ALL) from other small round blue cell tumors in children is very important for proper treatment, but sometimes difficult. CD45 is expressed on almost all-human leukocytes and not expressed on other small round blue cell tumors. Moreover, CD19 is expressed on all stages of B lineage cells and loss of this antigen is very rare in precursor B-cell ALL.

[Incidence and clinical significance of sex chromosome losses in bone marrow of patients with hematologic diseases].

Background: Loss of sex chromosomes in bone marrow is observed both in elderly persons as an aging phenomenon and in patients with hematologic malignancies. The purpose of this study was to evaluate the incidence and clinical significance of sex chromosome losses in patients with hematologic diseases, comparing the characteristics between patients with sole and secondary sex chromosome losses in conjunction with other chromosomal abnormalities.

Methods: Study group included 868 patients with hematologic diseases between June 1998 and May 2006.

The methylenetetrahydrofolate reductase C677T gene mutation is associated with hyperhomocysteinemia, cardiovascular disease and plasma B-type natriuretic peptide levels in Korea.

Background: Hyperhomocysteinemia is known to be a risk factor for cardiovascular diseases and is associated with a common mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene (677 C>T). The aims of this study were to confirm: 1) the association between the MTHFR C677T mutation and plasma homocysteine (Hcy) levels; 2) the MTHFR C677T mutation as a risk factor; 3) the association of the MTHFR C677T mutation and plasma B-type natriuretic peptide (BNP) levels; and 4) the correlation between Hcy and BNP levels in cardiovascular diseases.

Methods: A total of 227 patients for whom BNP was measured were enrolled in this study.

hTERT mRNA levels by real-time RT-PCR in acute myelogenous leukemia.

The purpose of this study was to investigate whether levels of hTERT mRNA, as determined by real-time RT-PCR, are associated with prognosis and clinical course in AML patients. Fifty-four bone marrow specimens from 21 patients diagnosed with de-novo AML were included. The level of hTERT mRNA was measured with the Telo TAGGG hTERT Quantification Kit (Roche Diagnostics, Mannheim, Germany), using a LightCycler Instrument (Roche Diagnostics).

Acute lymphoblastic leukemia without the Philadelphia chromosome occurring in chronic myelogenous leukemia with the Philadelphia chromosome.

The blast crisis in chronic myelogenous leukemia (CML) is related to the evolution of a Philadelphia chromosome (Ph)-positive clone. Secondary chromosomal abnormalities accompanied by t(9;22) are found in 70-80% of blast crises. Here we describe a patient with Ph-positive CML, who developed Ph-negative acute lymphoblastic leukemia (ALL).

In vitro differentiation of natural killer T cells from human cord blood CD34+ cells.

Natural killer T (NKT) cells are involved in innate immune defence and also in the regulation of adaptive immune responses. However, the development of NKT cells in vitro has not been fully characterized and culture conditions have not been fully optimized. In the present study, we found that an NKT cell fraction developed during the in vitro culture of cord blood (CB) CD34+ cells, and this was subsequently characterized both phenotypically and morphologically.