Acute promyelocytic leukemia with complex translocation t(5;17;15)(q35;q21;q22): case report and review of the literature.

The t(15;17)(q22;q21), resulting in PML-RARA fusion gene, is a characteristic chromosomal translocation in acute promyelocytic leukemia (APL). We report a pediatric APL case with a 3-way translocation: t(5;17;15)(q35;q21;q22). Complete blood cell counts of a 12-year-old girl, of pale appearance, showed pancytopenia with increased blasts. Morphology and immunophenotype of the leukemic cells were compatible with APL. Karyotype analysis showed t(5;17;15)(q35;q21;q22) and add(7)(q32). We detected the PML-RARA fusion gene by both reverse transcriptase-polymerase chain reaction and fluorescent in situ hybridization analysis. The patient underwent successful treatment with cytarabine with all-trans retinoic acid and anthracycline-based therapy.

Usefulness of delta value of platelet parameters on ADVIA 120 for the functional reactivity of stored platelets.

An agonist-induced expression of CD62P by flow cytometry analysis for evaluating platelet functional reactivity has some disadvantages. We investigated the usefulness of platelet parameters by ADVIA 120 to predict an agonist-induced expression of CD62P in stored platelets. The CD62P expression by flow cytometry and the platelet parameters by ADVIA 120 were studied in samples from 27 platelet pheresis products. Delta (Delta) values were calculated as the degree of change of the platelet parameters studied with or without adenosine 5'-diphosphate sodium (ADP) stimulation. The CD62P expression of the ADP-activated platelets were correlated with the Delta platelet count (r=0.517) in the short-term storage group (within 10 hr from preparation), with the platelet component distribution width (PCDW) without ADP (r=-0.744) and the DeltaPCDW (r=-0.755) in the long-term storage group (after 10 hr from preparation). Therefore, the delta values of platelet parameters on ADVIA 120 analysis in platelets between with and without ADP stimulation could be useful as a simple predictor for the functional reactivity of stored platelets.

VanB phenotype-vanA genotype Enterococcus faecium with heterogeneous expression of teicoplanin resistance.

Six VanB phenotype-vanA genotype isolates of Enterococcus faecium with heterogeneous expression of teicoplanin resistance which gave rise to an outbreak at a Korean tertiary care teaching hospital have IS1216V in the coding region of vanS. This could be the underlying cause of the VanB phenotype-vanA genotype with heterogeneous expression of teicoplanin resistance.

High-fluence 1064-nm Q-Switched Nd:YAG laser: Safe and effective treatment of café-au-lait macules in Asian patients.

OBJECTIVES: Café-au-lait macules (CALMs) are benign cutaneous hyperpigmentary disorders. Usually, laser therapies for cosmetic concerns result in more severe side effects in the people of Asian descent than that of Caucasians. Unfortunately, there is no gold standard for the laser treatment of CALMs in skin of people of Asian descent. To investigate the efficacy and safety of a high-fluence 1064-nm Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser treatment of CALMs in Asian patients. STUDY DESIGN: The medical records of 35 Korean patients (age range: 1 to 40 years old, mean age: 18.5 years) diagnosed with isolated CALMs were reviewed retrospectively. METHODS: The patients were treated with a 1064-nm Q-switched Nd:YAG laser. The parameters were a spot size of 7 mm, a fluence of 2.2-2.4 J/cm2 with a slow single sliding-stacking pass, and a pulse rate of 10 Hz with a 1-week interval for 20-50 sessions. RESULTS: At the week of the final treatment, all treated CALMs showed considerable pigmentation removal without any permanent side effects, such as scaring, mottled hypopigmentation and postinflammatory hyperpigmentation (PIH). All treated CALMs showed more than 50% clinical improvement. No recurrence was observed in any of the patients after 12 months of follow-up. CONCLUSION: A high-fluence 1064-nm Q-switched Nd:YAG laser treatment of CALMs in Asian patients is a safe and effective method without side effects and recurrence.

Performance evaluation of Samsung LABGEO(HC10) Hematology Analyzer.

CONTEXT: The Samsung LABGEO(HC10) Hematology Analyzer (LABGEO(HC10)) is a recently developed automated hematology analyzer that uses impedance technologies. The analyzer provides 18 parameters including 3-part differential at a maximum rate of 80 samples per hour. OBJECTIVE: To evaluate the performance of the LABGEO(HC10). DESIGN: We evaluated precision, linearity, carryover, and relationship for complete blood cell count parameters between the LABGEO(HC10) and the LH780 (Beckman Coulter Inc) in a university hospital in Korea according to the Clinical and Laboratory Standards Institute guidelines. Sample stability and differences due to the anticoagulant used (K2EDTA versus K3EDTA) were also evaluated. RESULTS: The LABGEO(HC10) showed linearity over a wide range and minimal carryover (<1%) for white blood cell, hemoglobin, red blood cell, and platelet parameters. Correlation between the LABGEO(HC10) and the LH780 was good for all complete blood cell count parameters (R > 0.92) except for mean corpuscular hemoglobin concentration. The bias estimated was acceptable for all parameters investigated except for monocyte count. Most parameters were stable until 24 hours both at room temperature and at 4°C. The difference by anticoagulant type was statistically insignificant for all parameters except for a few red cell parameters. CONCLUSIONS: The accurate results achievable and simplicity of operation make the unit recommendable for small to medium-sized laboratories.

Frequency, interobserver reproducibility and clinical significance of equivocal peaks in PCR clonality testing using Euroclonality/BIOMED-2 primers.

AIMS: PCR studies for lymphoid clonality are now widely employed, especially using Euroclonality/BIOMED-2 primers. Criteria for interpretation as a clonal result, however, have proven controversial. This study examines the frequency and clinical significance of equivocal amplification patterns and measures the interobserver reproducibility of clonality interpretations. METHODS: At our institution, results of each primer set are first classified as clonal, non-clonal or abnormal (equivocal peak on polyclonal background). Final results for all primer sets are then collectively reported as positive (≥1 clonal result), negative (non-clonal results) or indeterminate (≥1 abnormal result) for a clonal population. Results of 274 consecutive clonality cases were reviewed, and the interobserver reproducibility of individual primer set reactions and final results was determined in a subset of 30 cases. RESULTS: 44/161 (27%) B-cell and 50/163 (31%) T-cell cases contained at least one abnormal peak. Of these, 29 (64%) and 31 (62%), respectively, showed clonal results in another primer set. Interobserver reproducibility was excellent for most primer sets and for final interpretations, but only fair to good for IGK V-J and TCRB D-J1+2 primer sets. A definitive diagnosis of lymphoma was rendered in 93%, 20% and 6% of B-cell cases and 90%, 42%, and 14% of T-cell cases positive, indeterminate or negative for a clonal population, respectively. CONCLUSIONS: Using a subjective approach, abnormal (equivocal) peaks are frequently observed in routine practice. However, most cases with abnormal peaks contain clonal rearrangements in other primer sets, facilitating overall interpretation of final results with excellent interobserver reproducibility.

Hemophagocytosis by leukemic blasts in B lymphoblastic leukemia with t(12;21)(p13;q22); TEL-AML1 (ETV6-RUNX1): a case report.

Blasts showing hemophagocytosis have been very rarely reported in acute lymphoblastic leukemia. We report a pediatric case of B lymphoblastic leukemia (BLL) with t(12;21)(p13;q22); TEL-AML1 (ETV6-RUNX1) showing erythrophagocytosis and thrombophagocytosis by leukemic blasts. About 4% of the leukemic blasts in marrow aspirate smears showed phagocytosis of erythrocytes, platelets, or nuclear remnants in a 3-year-old Korean boy with a diagnosis of BLL. Conventional cytogenetics and molecular analysis revealed the presence of t(12;21)(p13;q22); TEL-AML1 (ETV6-RUNX1). The patient responded well to chemotherapy and is in a state of complete remission.

Characterization of a vancomycin-resistant Enterococcus faecium outbreak caused by 2 genetically different clones at a neonatal intensive care unit.

In July 2010, we identified an outbreak of vancomycin-resistant enterococci (VRE) in our 26-bed neonatal intensive care unit. We performed an epidemiological investigation after clinical cultures of 2 neonates were positive for VRE. Identification, susceptibility testing, and molecular characterization were performed. Cultures of 3 surveillance stool samples of inpatients and 5 environmental samples were positive for VRE. All isolates were identified as Enterococcus faecium containing the vanA gene. Two distinct clones were identified by performing pulsed-field gel electrophoresis. The 2 clones exhibited different pulsotypes, but they represented identical Tn1546 types. Two sequence types, ST18 and ST192, were identified among all of the isolates with multilocus sequence typing. Our investigation determined that the outbreak in the neonatal intensive care unit was caused by 2 genetically different clones. The outbreak may have occurred through clonal spread and horizontal transfer of the van gene.

Acute myeloid leukemia with t(16;21)(q24;q22) and eosinophilia: case report and review of the literature.

The t(16;21)(q24;q22), a rare chromosomal translocation involving chromosome 21 in de novo and therapy-related acute myeloid leukemia (AML), produces a RUNX1-CBFA2T3 fusion gene (previously AML1-MTG16) fusion gene. The translocation has been reported in 20 patients with AML, with eosinophilia present in 3 cases. Here we report a pediatric case of t(16;21)(q24;q22) in de novo AML with eosinophilia and suggest that eosinophilia is a hematologic characteristic of at least a subpopulation of AML with t(16;21)(q24;q22). A 4-year-old Korean girl was admitted with complaints of pale appearance and dizziness, and was diagnosed with acute myelomonocytic leukemia. On admission, laboratory evaluation revealed hemoglobin at 3.3 g/dL, platelets at 9.0 x 10(9)/L, and white blood cells at 9.1 x 10(9)/L with 10% eosinophils and 1% blasts. The bone marrow aspirate contained 31% blasts and 11% eosinophils. Flow cytometric analysis revealed the expression of CD13, CD14, CD19, CD33, CD34, and HLA-DR by the leukemic blasts. The karyotype was 47,XX, + 8,t(16;21)(q24;q22)[18]/46,XX[2]. Interphase fluorescence in situ hybridization analysis with a dual-color, dual-fusion translocation LSI AML1/ETO probe set for RUNX1 and RUNX1T1 produced three signals for each probe in 90% of interphases, but no fusion signals. We confirmed the presence of RUNX1-CBFA2T3 fusion transcripts with reverse transcriptase-polymerase chain reaction, using primers AML1ex5f1 and MTG16r2.

[Two cases of acute myeloid leukemia with t(16;21)(p11;q22) and TLS/FUS-ERG fusion transcripts].

Many AML-associated chromosomal abnormalities, such as t(8;21), t(15;17), inv(16), t(9;11), t(9;22) and t(6;9) are well known. The chromosomal aberration of t(16;21)(p11;q22) in AML is rare and it is known to be associated with poor prognosis, young age (median age, 22 yr), and involvement of various subtypes of the French-American-British classification. We report here 2 AML patients with t(16;21)(p11;q22), proved by conventional cytogenetics and/or reverse transcription (RT)-PCR. Erythrophagocytosis by leukemic blasts was observed in both of the cases. One patient was a 24 yr-old male with acute myelomonocytic leukemia. His karyotype was 46,XY,t(16;21)(p11;q22),del(18)(p11.2) and RT-PCR revealed the TLS/FUS-ERG fusion transcripts. Although he received allogeneic peripheral blood stem cell transplantation after the first remission, he died 9 months after the initial diagnosis due to relapse of the disease and graft-versus-host disease. The other patient was a 72 yr-old male with acute myeloid leukemia without maturation. His karyotype was 45,XY,-16,add(21)(q22) and the presence of t(16;21)(p11;q22) was detected by RT-PCR. He was transferred to another hospital with no more follow-up. We suggest that the presence of t(16;21)(p11;q22) and/or TLS/FUS-ERG fusion transcripts has to be considered in cases of AML with erythrophagocytosis.

A case of chronic myelogenous leukemia with e8a2 fusion transcript.

The Philadelphia chromosome and its corresponding fusion gene, BCR-ABL, is one of the best-known genetic abnormalities in hematological malignancies. Major BCR-ABL translocation is much more common in chronic myelogenous leukemia (CML) and minor BCR-ABL in acute lymphoblastic leukemia. We experienced an extraordinarily rare case of CML with an e8a2 variant. An unusual band, other than the common transcripts, was observed in reverse transcription-polymerase chain reaction (RT-PCR) for the BCR-ABL gene rearrangement. Sequence analysis of the PCR product revealed an 1172-bp e8a2 fusion with a 14-bp insertion of ABL intron Ia. The patient achieved a complete hematological response 3 months after imatinib treatment. It is necessary to keep in mind that an unexpected band revealed with RT-PCR may mean the presence of unusual fusion gene.

Genetic rearrangements of TN1546-like elements in vancomycin-resistant Enterococcus faecium isolates collected from hospitalized patients over a seven-year period.

The heterogeneity of Tn1546 results from point mutations, deletions, and the integration of insertion sequence (IS) elements. Among these variations, the presence of IS elements accounts for much of the heterogeneity. Such a rearrangement could play a key role in the evolution of the vanA gene cluster, and hence, it may modify its transferability. In this study, we characterized the consequence of Tn1546 in vanA-containing Enterococcus faecium isolates collected from patients over time. From 1998 to 2004, 57 vanA-containing E. faecium isolates were collected from hospitalized patients at Ajou University Hospital in Korea. PCR amplification of internal regions of Tn1546 was performed, and both DNA strands were directly sequenced by the dideoxy termination method. All isolates were divided into three main types, including the prototype, according to the distribution of IS elements integrated into Tn1546 elements. Type I was characterized by an IS1542 insertion in the orf2-vanR intergenic region and an IS1216V insertion in the vanX-vanY intergenic region. Type II was represented by the presence of two copies of IS1216V at the 3' end of IS1542 and in the vanX-vanY intergenic region, as well as IS1542 in the orf2-vanR intergenic region. Seventeen strains isolated from 1998 to 2000 represented type I, and 38 strains isolated from 2000 to 2004 represented type II. The remaining two isolates were the prototype. The tendency for the rearrangement of Tn1546 was that the sequences were shortened as time passed, especially at the left or the right end, and hence, this could gradually modulate their transferability.

First case of human babesiosis in Korea: detection and characterization of a novel type of Babesia sp. (KO1) similar to ovine babesia.

We report on the first case of human babesiosis in Korea. The intraerythrocytic parasite (KO1) in the patient's blood mainly appeared as paired pyriforms and ring forms; but Maltese cross forms were not seen, and the parasite showed morphological features consistent with those of the genus Babesia sensu stricto. The sequence of the 18S rRNA gene of KO1 was closely related to that of Babesia spp. isolated from sheep in China (similarity, 98%). The present study provides the first evidence of the presence of a hitherto unidentified, new type of Babesia parasite capable of infecting humans.

[Mechanism of VanB Phenotype in Vancomycin-Resistant Enterococci carrying vanA gene.].

BACKGROUND: Recently, vancomycin-resistant enterococci (VRE) with the vanA genotype that are susceptible to teicoplanin have been described in Japan, Taiwan, and Korea. The investigators suggested three point mutations in the putative sensor domain of vanS or impairment of accessory proteins VanY and VanZ as an explanation for the VanB phenotype-vanA genotype VRE. In this study, we analyzed Tn1546-like elements to determine the molecular mechanisms responsible for the impaired glycopeptide resistance of clinical VRE isolates with VanB phenotype-vanA genotype from Korea. METHODS: From 2001 to 2004, 28 clinical isolates of Enterococcus faecium with VanB phenotypevanA genotype were collected from 8 different university hospitals in diverse geographic areas in Korea. For structural analysis of Tn1546-like elements, PCR amplifications for internal regions of Tn1546 were performed. The purified PCR products were directly sequenced with an ABI Prism 3100 DNA sequencer. RESULTS: The sequence data of the vanS regulatory gene revealed that none of the isolates had any point mutations in this gene. All 28 isolates had a complete or incomplete deletion of vanY gene. Of these, 13 strains represented a complete deletion of vanZ, and 2 strains showed the deletion of nucleotides near the end point of vanX. CONCLUSIONS: The mechanism of VanB phenotype-vanA genotype in VRE isolates from Korea is not point mutations of vanS but the rearrangements of vanX, vanY and vanZ.