Search tips
Search criteria

Results 1-12 (12)

Clipboard (0)

Select a Filter Below

Year of Publication
1.  Streptococcus suis Causes Septic Arthritis and Bacteremia: Phenotypic Characterization and Molecular Confirmation 
Streptococcus suis is a swine pathogen that causes meningitis, septicemia, pneumonia, and endocarditis. The first case of human S. suis infection was reported in Denmark in 1968, and since then, this infection with has been reported in many countries, especially in Southeast Asia because of the high density of pigs in this region. We report the case of a patient with septic arthritis and bacteremia caused by S. suis. Cases in which S. suis is isolated from the joint fluid are very rare, and to the best of our knowledge, this is first case report of S. suis infection in Korea. The identity of this organism was confirmed by phenotypic characterization and 16S rRNA sequence analysis. An 81-yr-old Korean woman who presented with fever, arthralgia, and headache was admitted to a secondary referral center in Korea. Culture of aspirated joint fluid and blood samples showed the growth of S. suis biotype II, which was identified by the Vitek2 GPI and API 20 Strep systems (bioMérieux, USA), and this organism was susceptible to penicillin G and vancomycin. The 16S rRNA sequences of the blood culture isolates showed 99% homology with those of S. suis subsp. suis, which are reported in GenBank. The patient's fever subsided, and blood and joint cultures were negative for bacterial growth after antibiotic therapy; however, the swelling and pain in her left knee joint persisted. She plans to undergo total knee replacement.
PMCID: PMC3115998  PMID: 21474987
Streptococcus suis; Arthritis; Bacteremia
2.  Laboratory characteristics of recent hepatitis A in Korea: Ongoing epidemiological shift 
AIM: To evaluate seroprevalence of hepatitis A virus (HAV) antibody and investigate demographic, clinical, and laboratory features of recent cases in Korea.
METHODS: For the evaluation of hepatitis A seroprevalence, we analyzed the data from 3127 subjects including, healthcare workers and patients who visited Konkuk University Hospital, a secondary referral center, from January to October 2009. The sera with positive IgM were excluded from seroprevalence data for total HAV antibody. We retrospectively reviewed the electronic medical records of 419 patients with HAV, who were diagnosed by the presence of serum IgM antibodies against HAV. All patients presented at Konkuk University Hospital between August 2005 and September 2008.
RESULTS: Among 3127 sera tested, 1428 (45.7%) were positive for anti-HAV antibody. The seroprevalence was very low in teenagers or those in their twenties, increased in those in their thirties, and was > 90% in older patients. In children younger than 10 years, seroprevalence was increased again. Most patients with HAV hepatitis were in their twenties and thirties. The γ-glutamyl transpeptidase increased with age and was significantly higher in patients older than 30 years. Indicators of severity, such as decreased albumin and increased bilirubin, were also more prominent in the older age group; however, the leukocyte count was higher and the frequency of leukopenia was lower in younger patients than in older adults.
CONCLUSION: There has been an apparent epidemiological shift in HAV seroprevalence and a change in the peak age of HAV hepatitis. This study could provide baseline data of recent hepatitis A in Asia.
PMCID: PMC2835789  PMID: 20205283
Hepatitis A virus; Seroprevalence; Epidemiology; Korea
3.  Hepatitis B surface antigen levels at 6 months after treatment can predict the efficacy of lamivudine-adefovir combination therapy in patients with lamivudine-resistant chronic hepatitis B 
Clinical and Molecular Hepatology  2014;20(3):274-282.
Quantitation of hepatitis B surface antigen (HBsAg) is an increasingly popular method to determine the treatment response in chronic hepatitis B (CHB) patients. The clinical value of HBsAg level measurement during rescue therapy for lamivudine (LMV)-resistant CHB patients have not been evaluated to date. Therefore, this study investigated the correlation between HBsAg level and treatment response in LMV-resistant CHB patients treated with adefovir (ADV) add-on therapy.
LMV-resistant CHB patients treated with LMV-ADV combination therapy for over 2 years were included. HBsAg levels were measured at 6 month intervals until 1 year, and annually thereafter. Treatment response was assessed by determining the virological response (VR, undetectable HBV DNA levels) during treatment.
Fifty patients were included, of which 40 showed a VR. HBsAg levels were not different significantly at baseline (4.0 vs. 3.6 Log10 IU/mL, P=0.072). However, the HBsAg level decreased after 6 months of treatment in patients with a VR and became different significantly between the groups thereafter (3.9 vs. 3.3 at 6 months, P=0.002; 3.8 vs. 3.2 at 1 year, P=0.004; 3.9 vs. 3.2 at 2 years, P=0.008; 3.7 vs. 3.1 at 3 years, P =0.020).
The HBsAg level at 6 months after treatment can help predict treatment response.
PMCID: PMC4197176  PMID: 25320731
Hepatitis B, Chronic; Hepatitis B surface antigen; Lamivudine; Adefovir; Resistance
4.  HBsAg level and clinical course in patients with chronic hepatitis B treated with nucleoside analogue: five years of follow-up data 
Clinical and molecular hepatology  2013;19(4):409-416.
Quantification of the hepatitis B surface antigen (HBsAg) is increasingly used to determine the treatment response in patients with chronic hepatitis B (CHB). However, there are limited data about the clinical implications of Quantification of HBsAg long-term nucleoside analogue treatment for CHB. We investigated the clinical correlation between HBsAg level and clinical course in patients with CHB who are treated long-term with nucleoside analogues.
Patients with CHB who started lamivudine or entecavir monotherapy before June 2007 were enrolled. HBsAg was quantified at baseline, at 6 months, and at 1, 2, 3, 4, and 5 years of treatment. We compared data between the groups according to the presence or absence of a virological response (VR) and resistance.
Forty-eight patients were analyzed. There was no definite reduction in HBsAg level during the early period of treatment; differences in HBsAg levels between baseline and each time point were significant only at 5 years (P=0.028). In a subgroup analysis, this difference was significant only in non-resistant patients at 5 years (P=0.041).
There was no definite decrease in the HBsAg level during the early period of nucleoside analogue treatment, with long-term treatment being required to observe a significant reduction.
PMCID: PMC3894441  PMID: 24459646
HBsAg; Chronic hepatitis B; Lamivudine; Entecavir; Resistance
6.  Comparison of International Normalized Ratio Measurement between CoaguChek XS Plus and STA-R Coagulation Analyzers 
BioMed Research International  2012;2013:213109.
Background. Point-of-care testing (POCT) coagulometers are increasingly being used in the hospital setting. We investigated whether the prothrombin time international normalized ratio (INR) results by CoaguChek XS Plus (Roche Diagnostics GmbH, Mannheim, Germany) can be used reliably without being confirmed with the INR results by STA-R system (Diagnostica Stago S.A.S, Asnières sur Seine, France). Methods. A total of 118 INR measurements by CoaguChek XS Plus and STA-R were compared using Passing/Bablok regression analysis and Bland-Altman plot. Agreement of the INR measurements was further assessed in relation to dosing decision. Results. The correlation of INR measurements between CoaguChek XS Plus and STA-R was excellent (correlation coefficient = 0.964). The mean difference tended to increase as INR results increased and was 0.25 INR in the therapeutic range (2.0-3.0 INR). The overall agreement was fair to good (kappa = 0.679), and 21/118 (17.8%) INR measurements showed a difference in dosing decision. Conclusion. The positive bias of CoaguChek XS Plus may be obvious even in the therapeutic INR range, and dosing decision based on the CoaguChek XS Plus INR results would be different from that based on the STA-R results. The INR measurements by POCT coagulometers still need to be confirmed with the laboratory INR measurements.
PMCID: PMC3591144  PMID: 23509691
7.  Effects of granulocyte-colony stimulating factor and the expression of its receptor on various malignant cells 
The Korean Journal of Hematology  2012;47(3):219-224.
Granulocyte-colony stimulating factor (G-CSF) is extensively used to improve neutrophil count during anti-cancer chemotherapy. We investigated the effects of G-CSF on several leukemic cell lines and screened for the expression of the G-CSF receptor (G-CSFR) in various malignant cells.
We examined the effects of the most commonly used commercial forms of G-CSF (glycosylated lenograstim and nonglycosylated filgrastim) on various leukemic cell lines by flow cytometry. Moreover, we screened for the expression of G-CSFR mRNA in 38 solid tumor cell lines by using real-time PCR.
G-CSF stimulated proliferation (40-80% increase in proliferation in treated cells as compared to that in control cells) in 3 leukemic cell lines and induced differentiation of AML1/ETO+ leukemic cells. Among the 38 solid tumor cell lines, 5 cell lines (hepatoblastoma, 2 breast carcinoma, squamous cell carcinoma of the larynx, and melanoma cell lines) showed G-CSFR mRNA expression.
The results of the present study show that therapeutic G-CSF might stimulate the proliferation and differentiation of malignant cells with G-CSFR expression, suggesting that prescreening for G-CSFR expression in primary tumor cells may be necessary before using G-CSF for treatment.
PMCID: PMC3464340  PMID: 23071478
G-CSF; Differentiation; Proliferation; Solid tumor; AML
8.  Pre- and Post-transfusion Testing for Hepatitis B Virus Surface Antigen and Antibody in Blood Recipients: A Single-Institution Experience in an Area of High Endemicity 
Annals of Laboratory Medicine  2011;32(1):73-78.
Hepatitis B remains the most common transfusion-transmitted viral infection. We explored the current status of pre-transfusion screening and post-transfusion follow-up testing for hepatitis B virus (HBV) surface antigen (HBsAg) and antibodies (anti-HBs) in blood recipients from an area of high HBV endemicity.
A total of 7,780 blood recipients were transfused with at least 1 unit of blood component at a single university hospital in Korea between January 2006 and December 2009. Their medical records were reviewed, and their demographic and transfusion-related data were analyzed.
Pre-transfusion HBsAg and anti-HBs levels were tested in 77.6% (6,037/7,780) of the recipients. The results varied widely according to recipient age. In all, 32.8% (1,982/6,037) of the recipients who were tested had dual negative pre-transfusion results for HBsAg and anti-HBs and, therefore, were at increased risk of HBV transmission. Post-transfusion follow-up testing for HBsAg and/or anti-HBs was performed in 22% (436/1,982) of the increased-risk group.
Our data show that current transfusion-related laboratory testing practice is not sufficient to properly investigate possible post-transfusion infections. Routine laboratory tests, including HBsAg and anti-HBs, should be recommended in transfusion guidelines.
PMCID: PMC3255487  PMID: 22259782
Hepatitis B virus; Transmission; Transfusion; Recipients; Test
9.  CD4+CD25highFoxP3+ Regulatory T-cells in Hematologic Diseases 
CD4+CD25+ regulatory T-cells (Tregs) play a critical role in immune responses. We explored the status of Tregs in neoplastic and autoimmune hematologic diseases. We also evaluated the technical aspects of Treg measurement in terms of sample type and detection markers.
A total of 68 subjects were enrolled: 11 with AML, 8 with MDS, 10 with autoimmune diseases, and 39 controls. Tregs were analyzed in peripheral blood (PB) and bone marrow (BM) samples from each subject. Flow cytometry and the Human Regulatory T cell Staining Kit (eBioscience, USA) for CD4, CD25, and FoxP3 (forkhead box P3) were used.
The CD4+CD25high/CD4 and CD4+CD25highFoxP3+/CD4 populations were significantly correlated (P<0.0001). The AML and high-risk MDS groups had significantly larger CD4+CD25high/CD4 and CD4+CD25highFoxP3+/CD4 populations in PB than the autoimmune (P=0.007 and 0.012, respectively) and control groups (P=0.004 and 0.006, respectively). Comparable findings were observed in BM. The CD4+CD25highFoxP3+/CD4 population was significantly larger in PB than in BM (P=0.0003).
This study provides comparison data for Tregs in AML, MDS, and autoimmune hematologic diseases, and would be helpful for understanding the different immunologic bases of various hematologic diseases. Treg measurement using CD4, CD25, and/or FoxP3 in PB rather than in BM seems to be practical for routine hematologic purposes. Large-scale analysis of the diagnostic role of Treg measurement is needed.
PMCID: PMC3190000  PMID: 22016675
Regulatory T-cells; FoxP3; Hematologic disease; Peripheral blood; Bone marrow
10.  Emergence of Clostridium difficile Ribotype 027 in Korea 
Clostridium difficile infection (CDI) has markedly risen and is associated with hypervirulent ribotype 027 outbreaks in North America and Europe since 2003. The aims of this study were to determine the prevalence of ribotype 027 among C. difficile isolates in Korea, to characterize the ribotype 027 isolates, and to determine the clinical severity of CDI in patients infected with these isolates.
A total of 1,251 isolates of C. difficile recovered from stool specimens of suspected CDI patients at two tertiary-care hospitals and one commercial laboratory between 2002 and 2009. Genes for toxin A (tcdA), toxin B (tcdB), and binary toxin (cdtA and cdtB) were detected by PCR. Mutation in the tcdC gene was detected by sequencing after PCR amplification. For molecular genotyping, we performed PCR-ribotyping, pulsed-field gel electrophoresis (PFGE), and multilocus variable-number tandem-repeat analysis (MLVA). Minimum inhibitory concentrations of moxifloxacin were determined using Etest strips (AB bioMérieux, Sweden).
We identified 7 isolates as ribotype 027. These isolates had the same tcdC mutation as the epidemic strain, and 6 of them were resistant to moxifloxacin. The isolates were categorized into 3 different PFGE types and 7 different MLVA types. All the 7 cases had occurred sporadically.
C. difficile ribotype 027 is uncommon, but it has emerged in Korea. The spread of this ribotype should be closely monitored in order to avoid an outbreak of CDI in Korea.
PMCID: PMC3129351  PMID: 21779194
Clostridium difficile; PCR-ribotype 027; Pulsed-field gel electrophoresis; Multilocus variable-number tandem-repeat analysis
11.  Variant Burkitt-type translocation (8;22)(q24;q11) in plasma cell myeloma 
The Korean Journal of Hematology  2011;46(2):135-138.
Variant Burkitt-type translocation, t(8;22)(q24;q11), is very rare in plasma cell myeloma. We report a 51-year-old male patient with plasma cell myeloma, who showed t(8;22) (q24;q11). He suffered from pelvic pain for two months, and showed IgG, lambda type of monoclonal gammopathy (5.14 g/dL; 49.9% of protein). His bone marrow examination showed increased plasma cells (66.9% of all nucleated cells). Plasma cells (74.9% of all nucleated cells) and monoclonal spike (3.38 g/dL; 42.2%) persisted after three cycles of thalidomide and dexamethasone. Cytogenetic analysis showed complex chromosomal abnormalities: 44,XY,-1,t(2;5)(q33;q13),add(8)(q24.1),t(8;22)(q24.1;q11.2),add(10) (p15), der(11)t(1;11)(q21;p11.2),del(12)(p11.2p13),-13,-14,add(14)(q32),der(15)t(1;15)(p2 2;p11.2),-16,add(17)(q11.2),+21,+1-3mar[cp6]/46,XY[19]. To the best of our knowledge, this is the first report on plasma cell myeloma with a variant Burkitt-type t(8;22)(q24;q11) in the Korean patient. A review of 11 such cases in the literature, including the present case, implicated that plasma cell myeloma with t(8;22)(q24;q11) might be related to advanced stage and poor prognosis.
PMCID: PMC3128895  PMID: 21747887
Plasma cell myeloma; t(8;22)(q24;q11); Variant; Burkitt
12.  The Effects of Anti-insulin Antibodies and Cross-reactivity with Human Recombinant Insulin Analogues in the E170 Insulin Immunometric Assay 
Insulin assays are affected by varying degrees of interference from anti-insulin antibodies (IAs) and by cross-reactivity with recombinant insulin analogues. We evaluated the usefulness of the E170 insulin assay by assessing IA effects and cross-reactivity with 2 analogues.
Sera were obtained from 59 type 2 diabetes patients receiving continuous subcutaneous insulin infusion and 18 healthy controls. Insulin levels were determined using an E170 analyzer. To investigate the effects of IAs, we performed IA radioimmunoassays, and analyzed the differences between directly measured insulin (direct insulin) and polyethylene glycol (PEG)-treated insulins (free, IA-unbound; total, IA-bound and unbound insulin). We performed in-vitro cross-reactivity tests with insulin aspart and insulin glulisine.
In IA-positive patients, E170 free insulin levels measured using the E170 analyzer were significantly lower than the direct insulin levels. The mean value of the direct/free insulin ratio and IA-bound insulin, which were calculated as the difference between total and free insulin, increased significantly as endogenous IA levels increased. The E170 insulin assay showed low cross-reactivities with both analogues (< 0.7%).
IAs interfered with E170 insulin assay, and the extent of interference correlated with the IA levels, which may be attributable to the increase in IA-bound insulin, and not to an error in the assay. The E170 insulin assay may measure only endogenous insulin since cross-reactivity is low. Our results suggest that the measurement of free insulin after PEG pre-treatment could be useful for β cell function assessment in diabetic patients undergoing insulin therapy.
PMCID: PMC3111036  PMID: 21239867
Insulin; Insulin antibodies; Insulin immunoassay; Insulin analogues; Cross-reactivity

Results 1-12 (12)