Shine Young Kim

Evaluation of the Sysmex UF-100 Urine Cell Analyzer as a Screening Test to Reduce the Need for Urine Cultures for Community-Acquired Urinary Tract Infection

We evaluated the UF-100 flow cytometer (TOA Medical Electronics, Kobe, Japan) as a screening test for community-acquired urinary tract infection (UTI) to reduce the need for bacterial cultures. By comparing the test results for 330 urine samples with quantitative urine cultures, we established cutoff criteria for the UF-100. To rule out hospital-acquired UTI, all urine samples were from new patients who had not been admitted to a hospital within the previous month. Abacterial cutoff value of 3,000/microL provided the best discrimination for community-acquired UTI, with a sensitivity of 94.4% and a specificity of 73.4%compared with urine culture. It was possible to forgo 58.2% of cultures with only 4 false-negative results. With a bacterial cutoff value of 1,500/microL, the sensitivity improved to 100%, but the specificity declined to 49.8%, and only 38.5% of cultures could be avoided without any false-negative results. Screening with the UF-100 for community-acquired UTI is acceptable for routine use. It would improve the efficiency of the routine microbiology laboratory, and unnecessary antibiotic prescriptions could be reduced.

Evaluation of the Performances of AdvanSure TB/NTM Real Time PCR Kit for Detection of Mycobacteria in Respiratory Specimens

BACKGROUND PCR is a widely used method for rapid and accurate diagnosis of mycobacteriosis. The sensitivity and specificity of a real time PCR kit newly developed in Korea were evaluated for detecting mycobacteria in respiratory specimens. METHODS One hundred twenty nine Mycobacterium tuberculosis (TB) culture positive respiratory specimens (82 AFB stain positive and 47 stain negative specimens) were used for evaluation of the sensitivity. Nine non-tuberculous mycobacteria (NTM) culture positive specimens were also included. For evaluation of the specificity, 48 AFB stain and culture negative respiratory specimens from patients who were initially not fully excluded from mycobacterial diseases (specificity group 1) were used. Other 51 respiratory specimens from patients who were not suspected of mycobacterial diseases were also included (specificity group 2). Real time PCR was performed by using AdvanSure TB/NTM real time PCR Kit (LG Lifescience, Korea) and SLAN real time PCR detection system (LG Lifescience). The target genes of TB and NTM were IS6110 and rpoB, respectively. RESULTS Among 129 TB culture positive specimens, 82 of 82 AFB stain positive specimens (100%) and 35 of 47 (74.5%) stain negative specimens revealed real time PCR positivity for TB, resulting in sensitivity of 90.7%. Five of nine NTM culture positive specimens resulted in real time PCR positivity for NTM (55.6%). Forty seven of 48 specimens (97.9%) and all 51 specimens (100%) of the specificity group 1 and 2, respectively, were real time PCR negative for TB and NTM. CONCLUSIONS AdvanSure TB/NTM real time PCR Kit should be useful for detecting TB in respiratory specimens with high sensitivity and specificity.

Clinical Relevance of Elevated Levels of Serum Soluble Interleukin-2 Receptor alpha (sIL-2Rα) in Patients with Non-Hodgkin's Lymphoma

Levels of soluble interleukin-2 receptor alpha (sIL-2Rα) are known to increase in the sera of patients with certain malignancies, including malignant lymphoma. This study aimed to assess the clinical significance of the sIL-2Rα level in non-Hodgkins lymphoma (NHL). We used ELISA to measure the sIL-2Rα levels in 48 newly diagnosed and untreated patients with NHL and evaluated the correlation between the sIL-2Rα levels and clinical characteristics and the International Prognostic Index (IPI). We monitored serum sIL-2Rα in 7 patients to compare the changes in their clinical progress with these levels. High levels of serum sIL-2Rα (≥ 2,000 U/mL) correlated well with parameters defining the high risk group according to the IPI, i.e., high tumor burden at diagnosis (stage III+IV) and lactate dehydrogenase ≥ 472 U/L. The levels were also associated with B symptoms, bone marrow involvement, and poor response to therapy. The sIL-2Rα level decreased during complete remission and was elevated during disease progression or relapse. A high level of sIL-2Rα was significantly associated with a low survival rate. These results suggest that serum sIL-2Rα might be useful as a biomarker for evaluating the prognosis of patients with NHL at the time of diagnosis and during therapy. A well-controlled, large-scale study is needed to clarify the clinical significance of sIL-2Rα in specific groups of NHL.

Level of HOXA5 Hypermethylation in Acute Myeloid Leukemia is Associated with Short-term Outcome

Hypermethylation of the homeobox (HOX) gene promoter leads to decreased expression of the gene during tumor development and is thought to be correlated with the clinical outcome in leukemia. In this study, we performed pyrosequencing to quantify the methylation level of HOXA5 genes in the bone marrow samples obtained from 50 patients with AML and 19 normal controls. The methylation percentage of HOXA5 in AML patients (median=65.4%, interquartile range=35.9-72.3%) was higher than that of HOXA5 in control patients (median=43.1%, interquartile range=36.7-49.6%, Mann-Whitney U test, P=0.012). The patients of the AML group who had a high methylation percentage (>70%) had a good prognosis with a 3-yr overall survival (OS) of 82.5%, whereas the patients with a low methylation percentage (≤70%) showed a 3-yr OS of 40.5% (P=0.048). Cox proportional hazards regression showed that the methylation percentages of HOXA5 were independently associated with the 3-yr OS of AML patients, regardless of their karyotypes. We propose that the quantification of HOXA5 methylation by pyrosequencing may be useful for predicting short-term prognosis in AML. However, the limitations of our study are the small sample size and its preliminary nature. Thus, a larger study should be performed to clearly determine the relationships among HOXA5 methylation levels, cytogenetics, and prognosis in AML patients.

Elecsys Hepatitis B Surface Antigen Quantitative Assay: Performance Evaluation and Correlation with Hepatitis B Virus DNA during 96 Weeks of Follow-up in Chronic Hepatitis B Patients

Background Treatment for chronic hepatitis B aims to suppress virus replication and virus sequestration in hepatocytes. Covalently closed circular (ccc) DNA is the template for transcription of viral genes and is responsible for viral persistence. However, limited data are available for quantification of hepatitis B surface antigen (HBsAg) in Korea. Methods We evaluated the Elecsys HBsAg II quant assay (Roche Diagnostics, USA) for within-run, between-run, and between-day precisions, linearity, carryover, and clinical specificity. In total, 156 serum samples were evaluated for correlation between HBsAg and hepatitis B virus (HBV) DNA. Serial samples were obtained from 10 patients at 0, 12, 24, 48, 72, and 96 weeks during follow-up. Results The assay detected HBsAg in a linear range of 0.5-48,696 IU/mL. Within-run, between-run, and between-day CVs were 2.9-4.1%, 0-1.5%, and 1.5-4.9%, respectively. Cross-reactivity between potentially interfering substances was absent, and the carryover rate was 0.00002%. The correlation of measurements between the Elecsys assay and HBV DNA PCR was weak (r=0.438, P=0.002). For predicting virologic response, cutoff values of 10,275 IU/mL and 3,846 IU/mL at 12 and 24 weeks after treatment initiation showed positive predictive values of 77.1% and 85% and negative predictive values of 84.6% and 50%, respectively. Conclusions The Elecsys HBsAg II quant assay showed good performance for precision, linearity, carryover rate, and specificity. HBsAg level at baseline, 12 weeks, and 24 weeks after treatment initiation can predict virologic response, and the assay can be used for HBsAg quantification in clinical practice.

Incidence, Clinical Features, and Prognostic Impact of CALR Exon 9 Mutations in Essential Thrombocythemia and Primary Myelofibrosis: An Experience of a Single Tertiary Hospital in Korea

We evaluated the incidence, clinical characteristics, and prognostic impact of calreticulin (CALR) mutations in essential thrombocythemia (ET) and primary myelofibrosis (PMF) patients. In all, 48 ET and 14 PMF patients were enrolled, and the presence of CALR mutations was analyzed by direct sequencing. Patients were classified into three subgroups according to Janus kinase 2 (JAK2) V617F and CALR mutation status, and their clinical features and prognosis were compared. CALR mutations were detected in 15 (24.2%) patients, and the incidence increased to 50.0% in 30 JAK2 V617F mutation-negative cases. These included 11 patients with three known mutations (c.1092_1143del [seven cases], c.1154_1155insTTGTC [three cases], and c.1102_1135del [one case]) and 4 patients with novel mutations. ET patients carrying CALR mutation were younger, had lower white blood cell counts, and experienced less thrombosis during follow-up than those carrying JAK2 V617F mutation, while both patient groups showed similar clinical features and prognosis. In ET patients without JAK2 V617F mutation, CALR mutation did not significantly affect clinical manifestation and prognosis. In conclusion, CALR mutation analysis could be a useful diagnostic tool for ET and PMF in 50% of the cases without JAK2 V617F mutations. The prognostic impact of CALR mutations needs further investigation.

Distribution of Yeast and Mold Species Isolated from Clinical Specimens at 12 Hospitals in Korea during 2011

Department of Laboratory Medicine, Chonnam National University Medical School, Gwangju, Kyungpook National University of Medicine, Daegu, Chungnam National University of Medicine, Daejeon, Pusan National University Yangsan Hospital, Yangsan, The Catholic University of Korea College of Medicine, Seoul, Ajou University School of Medicine, Suwon, Yonsei University Wonju College of Medicine, Wonju, Chung-Ang University College of Medicine, Seoul, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Chonbuk National University Medical School, Jeonju, Yonsei University College of Medicine, Seoul, Korea

Quantitation of whole blood Epstein-Barr virus DNA is useful for assessing treatment response in patients with non-Hodgkin's lymphoma.

Introduction.  Epstein‐Barr virus (EBV) is a well‐known tumorigenic virus and is associated with lymphoproliferative disorders. Quantitations of EBV viral loads in plasma and peripheral blood mononuclear cells have been reported to be useful biomarkers for monitoring Hodgkin’s lymphoma and EBV‐associated non‐Hodgkin lymphoma (NHL).

Bacteroides fragilis vertebral osteomyelitis complicated by percutaneous epidural adhesiolysis.

Study Design. A case report of anaerobic vertebral osteomyelitis after percutaneous epidural adhesiolysis. Objective. To present a case of Bacteroides fragilis spondylodiscitis (BFS) secondary to percutaneous epidural adhesiolysis in a 38-year-old woman without predisposing factors. Summary of Background Data. Most cases of BFS result from hematogenous spread from a perianal abscess or sigmoidoscopy or local spread from an adjacent infection. However, BFS due to direct inoculation after percutaneous epidural adhesiolysis has not been previously reported. Methods. A 38-year-old woman presented with spondylodiscitis at the L4–L5 level 2 weeks after percutaneous epidural adhesiolysis. Despite empirical antibiotherapy, the spondylodiscitis and an epidural abscess became much aggravated. Open biopsy and curettage was performed, and metronidazole sensitive Bacteroides fragilis was identified by tissue culture. Results. Metronidazole was administrated for 5 weeks and symptoms were completely resolved. Follow-up magnetic resonance imaging showed that the spondylodiscitis was completely cured. Conclusion. This is the first report to be issued regarding BFS secondary to percutaneous epidural adhesiolysis. In our case, the pathogenesis may have been direct inoculation of Bacteroides fragilis into the epidural space and disc during percutaneous epidural adhesiolysis because the procedural approach used was adjacent to the anus.

A novel hemoglobin variant beta135(H13) Ala > Asp identified in an asymptomatic Korean family by direct sequencing: suggesting a new insight into Hb Beckman mutation

This article describes the clinical observation of a novel hemoglobin (Hb) variant found during the course of routine blood testing on a 61‐year‐old subject. The Hb variant was observed during HbA1c testing by ion‐exchange high‐performance liquid chromatography. Alkaline electrophoresis and DNA sequencing confirmed the presence of a new Hb variant, HBB:c.407C > A (p.Ala136Asp). This mutation has been reported to induce Hb Beckman variant in the Globin Gene Server. However, it was different from the only experimental report for Hb Beckman by Rahbar, Lee & Asmeron (p.Ala136Glu; Hb Beckman alpha2 beta2 135(H13) ala‐to‐glu: a new unstable variant and reduced oxygen affinity. Blood 78, 204a). And our case was asymptomatic with normal lab findings, while Rahbar et al.’s case showed the clinical manifestations of chronic anemia. This would be a report for a novel Hb variant suggesting new insight of Hb Beckman variant. This would be a report of a novel Hb variant suggesting new insights into Hb Beckman variant.