Increment of Serum Free Light Chain Kappa/Lambda Ratio in Patients with Renal Dysfunction

BACKGROUND: Since free light chain (FLC) is metabolized in the kidney, serum FLC concentration and kappa/lambda ratio are increased in patients with decreased renal function, even in the absence of monoclonal protein. In this study, we measured serum FLC levels to investigate the change in kappa/lambda ratios in relation to the severity of renal dysfunction. METHODS: Serum FLC concentrations were measured in 92 archived serum samples from patients diagnosed with chronic kidney disease using the Freelite assay (The Binding Site Group Ltd., UK), and kappa/lambda ratios were calculated. Serum creatinine levels were assayed to calculate estimated glomerular filtration rate (eGFR), and patients were divided into subgroups according to Kidney Disease Improving Global Outcomes (KDIGO) guidelines. We analyzed the difference in serum FLC levels and kappa/lambda ratios between subgroups. RESULTS: Serum FLC levels and kappa/lambda ratios increased depending on the severity of renal dysfunction. When patients were classified by setting cut-off value of eGFR as 60 mL/min/1.73 m2 (group A: eGFR ≥60 mL/min/1.73 m2, group B: < 60 mL/min/1.73 m2), the kappa/lambda ratio of group B was significantly higher than that of group A (group B: 1.60±0.46 vs. group A: 1.35±0.27, P=0.018). Serum FLC kappa/lambda ratios were within the previously determined renal reference interval (0.37–3.1). CONCLUSIONS: When interpreting results of serum FLC kappa/lambda ratio, renal function status should be considered in addition to hematological findings. If renal function deteriorates, a wider renal reference interval is preferred instead of the usual reference interval.

Comparison of YD URiSCAN PluScope Urine Microscopic Analyzer and Sysmex UF-1000i Flow Cytometry Systems

BACKGROUND: Urinalysis is one of the most commonly performed tests in clinical laboratories. In this study, we compared YD URiSCAN PluScope (PluScope; YD Diagnostics Corp., Korea) and Sysmex UF-1000i (UF-1000i; Sysmex Corp., Japan) for urine microscopic sediment analysis. METHODS: A total of 404 fresh urine samples were collected and analyzed using PluScope, UF-1000i, and manual microscopy. Quantitative correlation analyses for red blood cells (RBCs), white blood cells (WBCs), epithelial cells (EC), and casts were performed using Spearman's correlation. We evaluated agreement among the three systems by using weighted Cohen's κ and calculating concordance rates within one grade of difference for semiquantitative and qualitative parameters. RESULTS: There were moderate-high correlations between PluScope and UF-1000i for RBCs, WBCs, and ECs (r=0.542, 0.714, and 0.571, respectively) but negligible correlation for casts (r=0.186). There were moderate-high correlations between manual microscopy and automated devices for RBCs, WBCs, and ECs (r=0.550–0.745) but negligible correlations for casts (PluScope: r=0.247; UF-1000i: r=0.223). The pairwise concordance rates within one grade difference among the three methods were good for RBCs, WBCs, and ECs (95.0%–99.0%, κ=0.41–0.74). For casts, the concordance rate between PluScope and manual microscopy was fair (96.8%, κ=0.25), but concordance rates between UF-1000i and manual microscopy and between the two automated devices were poor (81.2% and 81.7%; κ=0.04 and 0.06, respectively). CONCLUSIONS: The two automated urine sediment analyzers showed a moderate-high correlation and concordance rate. They showed good correlations and concordance rates for RBCs, WBCs, and ECs. However, manual microscopic examinations are still needed for reviewing and confirming the presence of pathologic particles in urine, such as casts and crystals.

Usefulness of Serum Thymidine Kinase 1 as a Biomarker for Aggressive Clinical Behavior in B-cell Lymphoma

BACKGROUND: The cell cycle-dependent enzyme thymidine kinase 1 (TK1) is known to increase during cancer cell proliferation and has been reported as a prognostic marker for various hematologic malignancies and solid tumors. This study aimed to determine the reference interval in Korean healthy controls and to evaluate the usefulness of TK1 as a biomarker for aggressive clinical behavior in B-cell lymphoma patients. METHODS: We enrolled 72 previously untreated patients with B-cell lymphoma and 143 healthy controls. Serum TK1 levels were measured by chemiluminescence immunoassay (Liaison(R), DiaSorin, USA). We established the reference intervals in healthy controls. The diagnostic performance of serum TK1 was studied using receiver operating characteristic (ROC) analysis, and the correlation between the cutoff level for serum TK1 and clinical characteristics of B-cell lymphoma was evaluated. RESULTS: The reference range (95th percentile) of serum TK1 in healthy controls was 5.4-21.8 U/L. There was a clear difference in TK1 levels between patients with B-cell lymphoma and healthy controls (40.6+/-68.5 vs. 11.8+/-4.4 U/L, P or =15.2 U/L) correlated with the advanced clinical stage (P<0.001), bone marrow involvement (P=0.013), international prognostic index score (P=0.001), lactate dehydrogenase level (P=0.001), low Hb level (<12 g/dL) (P=0.028), and lymphocyte count (P=0.023). CONCLUSIONS: The serum TK1 level could serve as a useful biomarker for aggressive clinical behavior in B-cell lymphoma patients.

A Rare Case of Pediatric T Lymphoblastic Leukemia With t(11;17)(q23;q21) Involving Mixed-Lineage Leukemia Gene Rearrangement

No abstract available.

Evaluation of an Immunochromatographic Assay for the Rapid and Simultaneous Detection of Rotavirus and Adenovirus in Stool Samples

BACKGROUND: We evaluated the analytical and clinical performances of the SD BIOLINE Rota/Adeno Rapid kit (SD Rota/Adeno Rapid; Standard Diagnostics, Inc., Korea), an immunochromatographic assay (ICA), for the simultaneous detection of rotaviruses and adenoviruses in human stool samples. METHODS: We tested 400 clinical stool samples from patients with acute gastroenteritis and compared the ICA results with the results obtained by using ELISA, enzyme-linked fluorescent assays (ELFA), PCR, and multiplex reverse transcription-PCR (mRT-PCR). To assess the analytical performance of the SD BIOLINE Rota/Adeno Rapid kit, we determined its detection limit, reproducibility, cross-reactivity, and analytical reactivity for adenovirus subtypes, and performed interference studies. RESULTS: The overall agreement rates among the tested methods were 91.5% for rotavirus and 85.5% for adenovirus. On the basis of mRT-PCR, the overall agreement, positive agreement, and negative agreement rates of the ICA were 95.6%, 100%, and 94.9% for rotavirus, and 94.0%, 71.4%, and 94.8% for adenovirus, respectively. Using the ICA, we detected all the subtypes of adenovirus tested, but the analytical reactivities for adenovirus subtypes were different between the 4 adenovirus detection methods. The high reproducibility was confirmed, and no cross-reactivity or interference was detected. CONCLUSIONS: The SD BIOLINE Rota/Adeno Rapid kit showed acceptable analytical and clinical performances. However, interpretation of adenovirus positive/negative result should be cautious because of different detectability for adenovirus subtypes among adenovirus detection methods.

Comparison of Serum Fibrin-Fibrinogen Degradation Products with Carcinoembryonic Antigen as Biomarkers for Colon Cancer / 임상검사와정도관리

BACKGROUND: Colon cancer is the second most common cancer in males and fourth most common in females in Korea. The levels of serum fibrin-fibrinogen degradation products (FDP) are elevated in many malignancies due to haemostatic alterations resulting from carcinogenesis. We compared serum FDP with carcinoembryonic antigen (CEA) to assess whether FDP has a diagnostic value for colon cancer. METHODS: A total of 177 serum samples from 95 colon cancer patients and 82 healthy controls were provided by the Korea Cancer Center Hospital biobank. Serum FDP levels were measured using the DR-70 detection kits (AMDL, USA) and the levels of serum CEA were measured using the Roche E170 Analytics (Roche Diagnostics, Germany). RESULTS: The mean serum FDP and serum CEA levels were significantly higher in the cancer patient group (FDP, 1.65+/-1.44 microg/mL; range, 0.36 to 9.48; CEA, 99.99+/-321.74 ng/mL; range, 1.46 to 2,170.00) than in the control group (FDP, 0.58+/-0.46 microg/mL; range, 0.02 to 3.27, P<0.05; CEA, 1.66+/-1.18 ng/mL; range, 0.20 to 6.38, P<0.05). The receiver operating characteristic curve for FDP showed 80% clinical sensitivity and 83% specificity with an optimal cut-off of 0.81 microg/mL, while that for CEA exhibited 84% sensitivity and 94% specificity with a cut-off of 3.51 ng/mL. The area under the curve was 0.87 and 0.96 for serum FDP and CEA, respectively. A combination of the two markers showed 90% clinical sensitivity and 92% specificity for colon cancer. CONCLUSIONS: The diagnostic sensitivity for colon cancer was increased by using a combination of FDP and CEA.

A Case of Hepatosplenic T-cell Lymphoma Diagnosed by Bone Marrow Examination

Hepatosplenic T-cell lymphoma (HSTL) is a condition in which lymphoma cells infiltrate the sinusoids of the liver, spleen, and bone marrow, without lymph node involvement. We encountered a case of hepatosplenic T-cell lymphoma in a Vietnamese woman. The patient was hospitalized with epigastric pain and nausea. Splenomegaly and multiple poorly defined, low-attenuating nodular lesions in the liver were visualized on computed tomography (CT), and thrombocytopenia was noted. The lymph nodes were not significantly enlarged. Splenic biopsy could not be performed because of severe thrombocytopenia. Neoplastic lymphoid cells were present in bone marrow aspirates. Bone marrow sections revealed infiltration of CD3(+) and CD20(-) neoplastic lymphoid cells in the sinusoids. A clonality assay (IdentiClone T-Cell Receptor Delta Gene Clonality Assay; Invivoscribe Technologies, USA) showed gene rearrangements in the T-cell receptor delta gene. Thus, we made a confirmatory diagnosis of HSTL. When splenic biopsy is not available, bone marrow aspirates and clonality assessment may become useful diagnostic tools.

Utilization of Mean Peroxidase Index for Discrimination of Pseudoneutropenia

BACKGROUND: Autoanalyzer ADVIA2120 uses intracellular peroxidase concentration to perform white blood cell (WBC) differential. Therefore, in specimens containing neutrophils with low peroxidase concentration, neutrophils can be miscounted as monocytes or large unstained cells resulting in pseudoneutropenia. Myeloperoxidase deficiency can be detected by the mean peroxidase index (MPXI). The aims of this study are to establish the reference interval of MPXI and define a cut off value for manual slide review to discriminate pseudoneutropenia. METHODS: We calculated reference intervals as mean+/-2SD according to the indirect method of CLSI C28-A3 guideline from MPXI data of 5,802 individuals who took routine health checkup from April 2010 to June 2012. We performed manual slide review on specimens with low MPXI and compared neutrophil differential count of manual method with that of autoanalyzer. When neutrophil differential in manual slide review was >20%P higher than autoanalyzer result, it was regarded as a pseudoneutropenia. We performed ROC analysis using the MPXI results of samples with and without pseudoneutropenia to define a cutoff to discriminate pseudoneutropenia. RESULTS: The reference intervals of MPXI in total population, male, and female were -4.9 to 7.5, -5.5 to 7.3, and -4.5 to 7.5, respectively. The mean value of MPXI was significantly higher in female than in male and there was no difference by age. Twenty-two pseudoneutropenia samples from 7 patients were identified. ROC analysis yielded cutoff value of -20.7 with 94.9% of sensitivity and 77.3% of specificity. CONCLUSIONS: MPXI may be used in the manual slide review guideline for detecting pseudoneutropenia.

A Case of Heterozygous alpha(+)-Thalassemia Diagnosed in a Korean Family by Using Multiplex Ligation-Dependent Probe Amplification / 임상검사와정도관리

Alpha-thalassemia (alpha-thalassemia), which is prevalent in the Mediterranean region, is caused by deficient synthesis of the alpha-globin chains. It is commonly caused by HBA1 and/or HBA2 gene deletion and is diagnosed by DNA sequence analysis. The proband was a 38-year-old woman who was found to have microcytic and hypochromic anemia on a routine health checkup. Results of the Hb electrophoresis (EP) and direct sequencing of the HBA1 and HBA2 genes were found to be normal. As multiplex ligation-dependent probe amplification (MLPA) for the HBA1 and HBA2 genes revealed heterozygous deletion, she was diagnosed with heterozygous alpha+-thalassemia. Although routine laboratory tests revealed similar findings in the proband's father, brother and niece, MLPA revealed heterozygous deletions of the HBA1 or HBA2 gene in her brother and niece. In summary, we report a case of heterozygous alpha+-thalassemia in a Korean family that was detected by MLPA. We recommend that patients with suspected hemoglobinopathies should be followed-up further with MLPA, especially when Hb EP shows a normal pattern.

Type Distribution of Unexpected Red Cell Antibodies in Patients with Malignancy / 대한수혈학회지

BACKGROUND: Performance of antibody screening and identification tests before blood transfusion is important because the unexpected presence of red cell antibodies may cause hemolytic transfusion reactions. Many patients with malignancy undergo transfusion in order to overcome pancytopenia due to disease itself or chemotherapy. We investigated the type distribution of unexpected red cell antibodies in cancer patients and compared our results with those of other institutions. METHODS: From January 2008 to June 2011, 30,989 serum samples were screened using a LISS/Coombs card and ID-DiaCell I, II (DiaMed AG, Morat, Switzerland). Data-Cyte Plus Reagent Red Blood Cells (Medion Diagnostics, Dudingen, Switzerland) were used in performance of antibody identification tests. RESULTS: Out of 30,989 serum samples, 180 cases (0.58%) showed screening-positive results, and unexpected antibodies were identified in 72 cases. The type of unexpected antibody observed most often in cancer patients was a member of the Rh antibody group, anti-E in 17 cases (29.8%), followed by anti-Lea in five cases (8.8%) and anti-e in three cases (5.3%). While Rh group antibodies were observed in the colon cancer group, non-Rh group antibodies were observed in the rectal cancer group. And, in the genitourinary cancer group, Lewis group antibodies were more frequently detected than others. CONCLUSION: Findings from our study demonstrated a type distribution of unexpected red cell antibodies that was similar to those reported in previous studies. Compared with non-cancerous patients, no difference in type distribution of unexpected red cell antibodies was observed in cancer patients. Some antibodies were frequently observed in certain cancer groups. Further comprehensive research on unexpected antibodies based on location or histologic type of cancer is needed.

Clinical Significance of Oligoclonal Bands in Patients with Multiple Myeloma after Autologous Stem Cell Transplantation

BACKGROUND: Oligoclonal bands or isotype switch detectable by serum immunofixation electrophoresis (IFE) has been reported following chemotherapy and stem cell transplantation in patients with multiple myeloma (MM). We studied the significance of oligoclonal bands appearing after chemotherapy and autologous stem cell transplantation (ASCT) in Korean MM patients, and its impact on relapse. And we investigated the serial serum free light chain (FLC) ratio to establish its possible relationship with the relapse of MM. METHODS: We conducted a retrospective analysis of the serial serum IFE and FLC ratio in 16 MM patients treated with chemotherapy and ASCT. RESULTS: Eleven out of 16 patients (68.8%) had oligoclonal bands with or without isotype switch after ASCT and the median interval from transplantation was 2.0 months. And relapse or persistence rate of monoclonal gammopathy was lower in patients with oligoclonal bands (27.3% vs. 60.0%), though without statistical significance (P=0.299). In eight patients who developed oligoclonal bands and did not relapse, the serial serum FLC ratio was normal in range. But one patient who developed oligoclonal bands and showed increase of plasma cells in bone marrow, the serial serum FLC ratio was abnormal in range. CONCLUSIONS: The occurrence of oligoclonal bands after chemotherapy and ASCT in Korean MM patients is not significantly associated with adverse consequence of relapse or persistence of monoclonal gammopathy. Therefore oligoclonal bands may be not bad prognostic criterion. And the measurement of serum FLC ratio may be a useful indicator to predict relapse in MM patients who developed oligoclonal bands.

HDL Cholesterol Reduction during Rosiglitazone and Fenofibrate Treatment in a Type 2 Diabetes Mellitus Patient with Dyslipidemia / 대한진단검사의학회지

Thiazolidinediones (TZD), which are widely used as insulin sensitizers, and fibrates, which are lipid-lowering drugs, are used in the treatment of dyslipidemia that commonly accompanies diabetes. Several reports suggest elevated levels of high-density lipoprotein (HDL) cholesterol, but the paradoxical reduction of HDL cholesterol level during single or combined TZD and fibrate therapies has been occasionally reported. Herein, we report a case of paradoxical decrease in HDL cholesterol and apolipoprotein A-1 levels during rosiglitazone and fenofibrate treatment for the first time in Korea. The patient was a 56-yr-old man presenting with type 2 diabetes mellitus and dyslipidemia. His HDL cholesterol and apolipoprotein A-1 levels returned to normal after the cessation of fenofibrate therapy. Since diabetes is an established risk factor of cardiovascular diseases, low HDL cholesterol can be a key cause of concern for patients with diabetes. Therefore, HDL cholesterol level should be determined before and after starting TZD and/or fibrate therapy in diabetic patients.

Late-onset Neutropenia Following Rituximab Therapy as a Treatment of Diffuse Large B-cell Lymphoma: A Single Institution Study / 대한진단검사의학회지

BACKGROUND: Late-onset neutropenia (LON) following rituximab therapy has been reported in recent years. However, its incidence has not been reported in Korea. The aim of this study is to investigate the incidence of LON after rituximab therapy in Korean patients with diffuse large B-cell lymphoma (DLBCL). METHODS: Ninety-eight cases of DLBCL treated with rituximab between 2004 and 2008 were evaluated. We identified LON as defined by the neutrophil count of <1.5x10(9)/L without apparent cause after the recovery of neutrophil count following rituximab therapy. Bone marrow aspiration and biopsy specimens at the time of neutropenia were available for retrospective review in only 5 of the patients. RESULTS: LON was observed in 15 (15.3%) of the 98 patients. In the bone marrow specimens of the 5 patients, promyelocytes were relatively increased and the maturation index of the granulopoiesis was 2:1-3:1, which reflects maturation arrest. CONCLUSIONS: The incidence of LON following rituximab therapy was 15.3% in Korean patients with DLBCL. Although there are several hypotheses about the causative mechanisms of LON, we suggest that maturation arrest at the promyelocyte stage of granulopoiesis may be one of the mechanisms involved in the development of LON.

A Case of del(16)(q22) in a Patient with Acute Myeloid Leukemia with Complex Karyotype / 대한진단검사의학회지

Inversion of chromosome 16 [inv(16)(p13.1q22)] and t(16;16)(p13.1;q22) are associated with acute myelomonocytic leukemia (AMML) with eosinophilia and a favorable prognosis. On the other hand, patients with del(16)(q22) usually present with MDS or chronic myelomonocytic leukemia (CMML), which can evolve to AMML without eosinophilia, and this chromosomal aberration is associated with older age, a complex karyotype, and a poor prognosis. We report a case of AML with del(16)(q22) which showed a complex karyotype, absence of eosinophilia in bone marrow study and a poor response to chemotherapy.

Development of Indicators to Assess the Stability of Remnant Blood Samples Stored in a Biobank: Experience at One Institution / 대한진단검사의학회지

BACKGROUND: One of the major concerns with biobanking is the absence of standard operating procedures to eliminate pre-analytical variation arising from sample collection, preparation, and storage. Currently, there is a lack of tools to carry out quality control procedures for stored blood samples. The aim of this study is to assess the quality of stored blood samples in our biobank and to suggest appropriate indicators for their quality control. METHODS: The stored blood samples that we tested have been registered into our biobank since 2003. These were transferred to our biobank after carrying out routine requested tests, because the samples would have otherwise been discarded. For the purpose of quality control, we analyzed the concentrations and the integrity of DNA and RNA extracted from the stored samples and tested the levels of several serum proteins; the results were compared with the corresponding pre-storage levels. RESULTS: A total of 19 samples were stored from 2006 to 2009. Of the 22 samples stored between 2003 and 2005, 50% showed complete DNA integrity. However, sufficient RNA integrity was noted in only 1 sample stored as recently as 2009. High blood urea nitrogen levels were also noted in the stored sera, but the increase did not correlate to the duration of storage. CONCLUSIONS: The amount and integrity of nucleic acids extracted from stored blood samples are potential indicators that can be used for quality control. A guideline for the quality assessment of stored blood samples in a biobank is urgently needed.

The First Clinical Trial of Antioxidant, Carvedilol-Eluting Stent in Coronary Artery Diseases

BACKGROUND AND OBJECTIVES: Carvedilol is a beta- and alpha-receptor blocker, a direct inhibitor of smooth muscle cell proliferation and migration, and it produced a significant suppression of neointimal hyperplasia in our porcine experiment. The purpose of the study was to investigate the safety and efficacy of carvedilol-eluting BiodiVysio stent implantation for de novo lesions. SUBJECTS AND METHODS: We performed a prospective randomized trial to compare two types of stents for revascularization in 39 patients [Group I (carvedilol-eluting stent): n=20, 58.3+/-11.1 years, and Group II (control stent): n=19, 59.9+/-8.5 years]. The primary effective end points were major adverse cardiac events (MACE): cardiac death, acute myocardial infarction, target lesion revascularization (TLR), in-stent restenosis and late lumen loss at the one-year clinical and angiographic follow-up. RESULTS: All the stents were successfully deployed and the patients were discharged without experiencing any clinical events. The baseline clinical characteristics, baseline diameter stenosis and minimal luminal diameter were not different between the two groups. The follow-up diameter stenosis and late loss were significantly lower in the group I compared with group II (23.1+/-12.7% vs. 47.3+/-23.6%, p=0.012; and 0.52+/-0.26 mm vs. 1.12+/-0.67 mm; p=0.020, respectively). There were no TLR and MACE in group I; however the differences were not significant [0% (0/20) vs. 10.5% (2/19); p=0.231 and 0% (0/20) vs. 15.8% (3/19), p=0.106, respectively]. CONCLUSION: Carvediloleluting stents appear feasible to use and they may be effective in the prevention of coronary restenosis. These results warrant further confirmation with a large, randomized multi-center trial.

Unpredicted Severe Toxicity after 5-Fluorouracil Treatment due to Dihydropyrimidine Dehydrogenase Deficiency

Dihydropyrimidine dehydrogenase (DPD) is the initial and rate-limiting enzyme in the catabolism of 5-fluorouracil (5-FU). Thus, patients with a DPD deficiency are at risk of developing severe 5-FU-associated toxicity. A 37-year-old female with gastric cancer underwent a curative operation, followed by adjuvant chemotherapy consisting of 5-FU and epirubicin. After the first cycle of chemotherapy, the patient manifested grade 2 mucositis and febrile neutropenia, and when her treatment was subsequently continued with doxifluridine she developed severe mucositis and febrile neutropenia. A PCR study revealed that her DPD mRNA level was lower than that in a control group. Thus, when considering the routine use of 5-FU for the treatment of cancer patients, an analysis of DPD activity or screening for DPD mutations is warranted in confined patients who experience unpredicted severe toxicity after initial 5-FU administration, even though DPD deficiency is a rare metabolic defect.

The Effect of the Probucol-Loaded BiodivYsioTM DD Stent on Inhibition of Neointimal Proliferation in Porcine Coronary Stent Restenosis Model

BACKGROUND AND OBJECTIVES: In a recent multicenter trial probucol was found to reduce stent restenosis by improving the lumen dimension. The probucol was administered for 2 weeks before, and 4 weeks after, stenting. The release of the drug at the site of a vascular injury, via polymer-coated stents, helps achieve an effective local concentration. The feasibility of a probucol stent coating in reducing in-stent restenosis was assessed. MATERIALS AND METHODS: The probucol loading and in vitro release were assessed using BiodivYsioTM stents, in a 50 mg/mL probucol solution. After being dip-coated with probucol (n=8), or a control (n=8) solution, the stents were implanted in 8 pigs. Angiography and histopathological analyses were performed 28 days later. RESULTS: The total probucol loading was 52+/-16 microgram/stent, with no release for up to 72 hours after loading. No pig died until sacrifice. On angiography, the reference and minimum lumen diameters showed no significant differences between the two groups, with similar diameters stenosis (8.7+/-3.68 vs. 13.3+/-4.18%, p=0.120). On histomorphometry, the injury scores, vessel, lumen and neointimal areas showed no significant differences between the groups, with similar areas of stenosis (23.1+/-12.39 vs. 25.2+/-8.22%, p=0.671). The degrees of re-endothelialization, inflammation and smooth muscle cell proliferation were not significantly different. CONCLUSIONS: Probucol can be loaded onto a polymer-coated stent, and does not release from the stent for up to 72 hours after loading. About 52 microgram probucol per stent does not reduce in-stent restenosis in porcine coronary arteries.

Glutathione S-Transferase (GST) Gene Deletions in Korean Patients with Acute Myeloid Leukemia or Myelodysplastic Syndrome / 대한혈액학회지

BACKGROUND: There have been many studies on the association between the glutathione S- transferase (GST) genotype and the susceptibility to acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) and the results are still controversial. We tested whether the homozygous null genotype of GST mu 1 (GSTM1) and GST theta 1 (GSTT1) genes influences the risk for MDS and AML. METHODS: We analyzed bone marrow DNA samples from 54 patients with AML or MDS (14 de novo AML, 7 secondary AML, and 33 MDS) and peripheral blood DNA samples from 75 cancer-free controls. The GSTM1 and GSTT1 genotypes were analyzed by multiplex polymerase chain reaction (PCR). RESULTS: The frequencies of GSTM1 null and GSTT1 null were not significantly increased in AML/MDS cases compared with those in controls. CONCLUSION: Our data suggest that GSTM1 and GSTT1 null genotypes may not predispose to AML/MDS in Korean population.

A myocardial sling in proximal right coronary artery / 대한내과학회지

Myocardial bridge is characterized by systolic compression of a portion of the coronary artery by a segment of overlying myocardium, commonly involves the middle segment of left anterior descending coronary artery. We present a case report of coronary angiographic evidence of systolic short segmental constriction in the proximal right coronary artery (RCA). A 42 year-old man presented with atypical chest discomfort and palpitation. Electrocardiography showed complete AV block with complete AH block on intracardiac electrocardiogram. Myocardial SPECT imaging demonstrated a mild reversible anterior and inferior wall perfusion defect. Diagnostic coronary angiogram revealed short segmental myocardial sling with wedge-shaped systolic compression in the proximal RCA.