Inhibition of angiotensin converting enzyme increases PKCβI isoform expression via activation of substance P and bradykinin receptors in cultured astrocytes of mice

Background@#Angiotensin-converting enzyme inhibitor (ACEi) inhibits the catalysis of angiotensin I to angiotensin II and the degradation of substance P (SP) and bradykinin (BK). While the possible relationship between ACEi and SP in nociceptive mice was recently suggested, the effect of ACEi on signal transduction in astrocytes remains unclear. @*Objectives@#This study examined whether ACE inhibition with captopril or enalapril modulates the levels of SP and BK in primary cultured astrocytes and whether this change modulates PKC isoforms (PKCα, PKCβI, and PKCε) expression in cultured astrocytes. @*Methods@#Immunocytochemistry and Western blot analysis were performed to examine the changes in the levels of SP and BK and the expression of the PKC isoforms in primary cultured astrocytes, respectively. @*Results@#The treatment of captopril or enalapril increased the immunoreactivity of SP and BK significantly in glial fibrillary acidic protein-positive cultured astrocytes. These increases were suppressed by a pretreatment with an angiotensin-converting enzyme.In addition, treatment with captopril increased the expression of the PKCβI isoform in cultured astrocytes, while there were no changes in the expression of the PKCα and PKCε isoforms after the captopril treatment. The captopril-induced increased expression of the PKCβI isoform was inhibited by a pretreatment with the neurokinin-1 receptor antagonist, L-733,060, the BK B 1 receptor antagonist, R 715, or the BK B 2 receptor antagonist, HOE 140. @*Conclusions@#These results suggest that ACE inhibition with captopril or enalapril increases the levels of SP and BK in cultured astrocytes and that the activation of SP and BK receptors mediates the captopril-induced increase in the expression of the PKCβI isoform.

Verification of the Performance of the Panbio COVID-19 Ag Rapid Test Device for Implementation in the Clinical Laboratory / 이화의대지

Objectives@#The Panbio COVID-19 Ag Rapid Test Device (Panbio COVID-19 Ag, Abbott Rapid Diagnostics) is a lateral flow immunochromatographic assay targeting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleoprotein in nasopharyngeal specimens for the diagnosis of coronavirus disease 2019 (COVID-19). This study aimed to verify the performance of the Panbio COVID-19 Ag for implementation in clinical laboratories. @*Methods@#Sixty nasopharyngeal swab specimens (30 positive and 30 negative) dipped in transport medium, and COVID-19 was confirmed using real-time RT-PCR using Allplex SARS-CoV-2 assay (Seegene), were tested using the Panbio COVID-19 Ag. Reproducibility was evaluated using positive and negative control materials. Sensitivity and specificity were calculated based on the results of realtime RT-PCR as the standard test method. @*Results@#Reproducibility was confirmed by the consistent results of repeated tests of the quality control materials. The overall sensitivity and specificity of Panbio COVID-19 Ag were 50.0% and 100.0%, respectively. Panbio COVID-19 Ag demonstrated high sensitivity (88.2%) in analyzing the detection limit cycle threshold (Ct) value of 26.67 provided by the manufacturer as a positive criterion, and the sensitivity was 100.0% for the positive criterion of Ct values <25, although it was less sensitive for Ct ≥ 25. @*Conclusion@#Considering the high sensitivity for positive samples with Ct values <25 and the rapid turnaround of results, Panbio COVID-19 Ag can be used in clinical laboratories to diagnose COVID-19 in limited settings.

Evaluation of the AdvanSure TB/NTM Plus Real-Time PCR Assay for the Simultaneous Detection of Mycobacterium tuberculosis and Nontuberculous Mycobacteria from Clinical Specimens / 대한임상미생물학회지

Background@#The AdvanSure TB/NTM plus real-time PCR (AdvanSure plus PCR; LG Chem., Korea) assay has been developed to increase the diagnostic sensitivity of nontuberculous mycobacteria (NTM) compared with the currently used the AdvanSure TB/NTM real-time PCR (AdvanSure PCR;LG Chem., Korea) assay. In this study, we aimed to evaluate the performance of the AdvanSure plus PCR comparing the results with mycobacterial culture and the AdvanSure PCR. @*Methods@#Patients (n=199) with suspected NTM or Mycobacterium tuberculosis complex (MTC) were tested using AdvanSure plus PCR, AdvanSure PCR, acid-fast bacilli staining, and mycobacteria culture. Additionally, 200 DNA samples (n=100, MTC and n=100, NTM) were obtained from positive MTC or NTM cultures for evaluation using the AdvanSure plus PCR assay. @*Results@#The two real-time PCR systems showed a 94.0% (n=187/199) concordance rate (Kappa=0.94). Based on culture results, the sensitivity and specificity for the detection of MTC were 100% (45/45) and 83.8% (129/154) using AdvanSure plus PCR, and 100.0% (45/45) and 99.3% (153/154) using AdvanSure PCR, respectively. The sensitivity and specificity for NTM detection were 68.0% (n=17/25) and 90.2% (n=157/174), respectively, with AdvanSure plus PCR, and 64.0% (n=16/25) and 95.4% (n=166/174), respectively, using AdvanSure PCR. With culturepositive samples, AdvanSure plus PCR tested positive for 100% of both the MTC and NTM specimens. Seven (out of 200) culture-positive samples tested positive for both MTC and NTM using the AdvanSure plus PCR. @*Conclusion@#AdvanSure plus PCR had increased sensitivity but decreased specificity compared with AdvanSure PCR for the detection of NTM. The AdvanSure plus PCR assay can be used for the simultaneous detection of MTC and NTM in direct specimen and culture.

Performance of Xpert Carba-R Assay for Identification of Carbapenemase Gene in the Clinical Microbiology Laboratory / 이화의대지

Objectives@#The Xpert Carba-R Assay is a diagnostic test designed for the rapid detectionand differentiation of the blaKPC, blaNDM, blaVIM, blaOXA-48, and blaIMP-1 genes. We verifiedthe performance of Xpert Carba-R Assay for identification of carbapenemase genein the clinical microbiology laboratory. @*Methods@#The analytical limit of detection was determined with two suspensions ofcarbapenemase-producing Enterobacteriaceae (CPE) isolates (KPC and NDM). A totalof 52 specimens were evaluated: 21 bacterial isolates from clinical specimens, 21 rectalswabs, and 10 contrived stool specimens. @*Results@#In bacterial isolates, concordant results between the Xpert Carba-R Assayand PCR were found in 20 of 21; 8 KPC, 8 NDM, 1 IMP, and 2 multiple carbapenamasegenes (KPC/NDM, NDM/OXA) were detected both by Xpert Carba-R Assay and PCR.In one GES-positive isolate, Xpert Carba-R Assay showed a negative result as expected.One VIM-positive isolate tested negative by Xpert Carba-R Assay. Complete concordancewas seen in rectal swab specimens: 4 specimens with KPC and 17 specimenswith negative results both by Xpert Carba-R Assay and surveillance culture. Among the10 contrived stool specimens, Xpert Carba-R Assay detected carbapenemase genes in9 specimens as expected according to the CPE strains spiked into the contrived stool; 2KPC, 4 NDM, 1 IMP, and 2 multiple carabapenamase genes (NDM/KPC, NDM/OXA).One VIM-positive specimen tested negative by Xpert Carba-R Assay. @*Conclusion@#In conclusion, the Xpert Carba-R Assay can be used to identify carbapenemasegene in bacterial isolates cultured from clinical specimens and detect CPE carrierusing rectal swab in clinical laboratories.

Serotype Distribution and Antimicrobial Resistance of Invasive and Noninvasive Streptococcus pneumoniae Isolates in Korea between 2014 and 2016

BACKGROUND: Several factors contribute to differences in Streptococcus pneumoniae serotype distribution. We investigated the serotype distribution and antimicrobial resistance of S. pneumoniae isolated between 2014 and 2016 in Korea. METHODS: We collected a total of 1,855 S. pneumoniae isolates from 44 hospitals between May 2014 and May 2016, and analyzed the serotypes by sequential multiplex PCR. We investigated the distribution of each serotype by patient age, source of the clinical specimen, and antimicrobial resistance pattern. RESULTS: The most common serotypes were 11A (10.1%), followed by 19A (8.8%), 3 (8.5%), 34 (8.1%), 23A (7.3%), and 35B (6.2%). The major invasive serotypes were 3 (12.6%), 19A (7.8%), 34 (7.8%), 10A (6.8%), and 11A (6.8%). Serotypes 10A, 15B, 19A, and 12F were more common in patients ≤5 years old, while serotype 3 was more common in patients ≥65 years old compared with the other age groups. The coverage rates of pneumococcal conjugate vaccine (PCV)7, PCV10, PCV13, and pneumococcal polysaccharide vaccine 23 were 11.8%, 12.12%, 33.3%, and 53.6%, respectively. Of the 1,855 isolates, 857 (46.2%) were multi-drug resistant (MDR), with serotypes 11A and 19A predominant among the MDR strains. The resistance rates against penicillin, cefotaxime, and levofloxacin were 22.8%, 12.5%, and 9.4%, respectively. CONCLUSIONS: There were significant changes in the major S. pneumoniae serotypes in the community. Non-PCV13 serotypes increased in patients ≤5 years old following the introduction of national immunization programs with the 10- and 13-polyvalent vaccines.

Serotyping and Antimicrobial Susceptibility of Salmonella Isolated in Korea in 2015 / 대한임상미생물학회지

BACKGROUND: Salmonella is an important pathogen that causes gastroenteritis and sepsis in humans. Recently, changes in serotype prevalence and an increase in antimicrobial resistance have been reported. This study investigated the distribution of Salmonella serotypes and determined the antimicrobial susceptibility of various strains. METHODS: We collected 113 Salmonella isolates other than Salmonella serotype Typhi from 18 university hospitals in 2015. The serotypes were identified by Salmonella antisera O and H according to the Kauffman White scheme. Antimicrobial susceptibility tests for 12 antibiotics were performed using the disk diffusion method or E-test. RESULTS: We identified 22 serotypes. Serotype group B (44.2%) was the most common, followed by groups C (34.5%) and D (21.2%). Salmonella I 4,[5],12:i:- (23.0%), S. Enteritidis (16.8%), and S. Typhimurium (12.4%) were the most common species. Resistance rates for ampicillin, chloramphenicol, ceftriaxone, and trimethoprim/sulfamethoxazole were 46.9%, 18.5%, 8.8%, and 5.3%, respectively. The intermediate resistance rate to ciprofloxacin was 29.2%. Six isolates were extended-spectrum β-lactamase (ESBL) producers, including 5 bla(CTX-M-15) and 1 bla(CTX-M-55). CONCLUSION: There have been changes in the serotype prevalence and antimicrobial resistance of Salmonella in Korea, with a high prevalence of CTX-M 15-positive strains. Continuous monitoring of Salmonella serotypes and antimicrobial resistance is warranted.

Comparison of PANA RealTyper HPV Kit with AdvanSure HPV GenoBlot Assay for Human Papillomavirus Genotyping / 대한임상미생물학회지

BACKGROUND: The PANA RealTyper HPV kit (PANAGENE, Korea; PANA RealTyper) was developed to genotype human papillomavirus (HPV) and was based on multiplex real-time PCR amplification and melting curve analysis. In this study, we compared PANA RealTyper to the AdvanSure HPV GenoBlot assay (LG Life Sciences, Korea; AdvanSure assay) and attempted to evaluate the performance of PANA RealTyper. METHODS: A total of 60 cervical specimens were collected from women undergoing routine cervical cancer screening. The AdvanSure assay and PANA RealTyper kit identified the same 20 high-risk genotypes. However, the AdvanSure assay identified 15 low-risk genotypes, while the PANA RealTyper kit identified only 2 but detected 18 low-risk genotypes. RESULTS: Among the total 60 specimens, 54 high-risk genotypes (40 specimens) and 20 low-risk genotypes (18 specimens) were detected. The agreement rates of the assays ranged from 94.4 to 100% for high-risk genotypes. Among 9 genotypes that were positive in the PANA RealTyper kit but negative in the AdvanSure assay, 7 were confirmed as true positive (HPV genotypes 16 (n=1), 39 (n=1), 52 (n=1), 58 (n=2), 68 (n=2)). Among 4 genotypes that were negative in the PANA RealTyper kit but positive in the AdvanSure assay, 3 were confirmed as HPV genotype 59. Among the 19 low-risk genotypes positive in the AdvanSure assay, there were 2 cases of HPV 6 and 1 case of HPV 11. In comparison, only 1 positive case of HPV 6 was determined by the PANA RealTyper kit. CONCLUSION: The PANA RealTyper kit was comparable with the AdvanSure assay. The PANA RealTyper kit would be useful and suitable for HPV genotyping in the clinical laboratory.

Multicenter Study on the Association of Positive Helicobacter pylori Stool Antigen to Anemia in Children / 대한임상미생물학회지

BACKGROUND: Helicobacter pylori infection in children causes gastrointestinal symptoms and iron deficiency anemia. This study aimed to investigate trends in H. pylori stool antigen (HpSA) positivity in children and the relationship between HpSA test results and anemia. METHODS: We analyzed the results of 2,762 HpSA tests and the correlation of hemoglobin and ferritin with HpSA in patients aged 0–18 years from 2008 to 2014 at a tertiary care center. Additionally, we prospectively evaluated HpSA test results and correlation with hemoglobin in 352 specimens obtained from five centers. RESULTS: From 2008-2014, the mean positive rate of the HpSA test was 5.8%, with a high of 9.1% in 2012 and a low of 2.3% in 2013. The positive rate correlated with age: 2.9% in 0–6-year-olds, 5.8% in 7–12-year-olds, and 10.6% in 13–18-year-olds (P < 0.0001). There was no difference in HpSA positivity in patients with (7.0%) and without (5.7%) anemia. Ferritin was significantly lower in patients with positive HpSA results than in those with negative results (P=0.0001). In a multicenter study, the positive rate of HpSA was 16.8%. CONCLUSION: The rate of HpSA positivity was 5.8% in pediatric patients at a single center from 2008–2014, and this rate increased with age. Helicobacter pylori infection may be associated with iron deficiency, as ferritin level was significantly lower in HpSA-positive patients than HpSA-negative patients.

GATA1 Expression in BCR/ABL1-negative Myeloproliferative Neoplasms

BACKGROUND: This study aimed to determine GATA1 expression levels to better characterize subgroups in BCR/ABL1-negative myeloproliferative neoplasms (MPNs). METHODS: This study enrolled 49 patients diagnosed as having BCR/ABL1-negative MPN on the basis of the 2016 World Health Organization classification : nine polycythemia vera (PV), 17 essential thrombocythemia (ET), 12 prefibrotic primary myelofibrosis (prePMF), and 11 overt primary myelofibrosis (PMF). Relevant clinical and laboratory data were retrieved from the medical records. The molecular analysis of CALR and MPL mutations and quantification of JAK2 V617F allele burden were performed. GATA1 expression was assessed by an immunohistochemical assay on bone marrow biopsy. GATA1 expression was analyzed serially in 18 patients. RESULTS: GATA1 expression decreased significantly in PMF compared with that in other subtypes, while no statistical difference was identified between ET and prePMF. GATA1 expression did not differ according to the mutation profiles or the allele burden of JAK2 V617F, but it decreased significantly in patients with overt fibrosis or leukemic transformation. CONCLUSIONS: Our results suggest that GATA1 expression is significantly low in PMF and decreases with progressive fibrosis and possibly with leukemic transformation, although our attempt to accurately distinguish between subgroups using GATA1 immunohistochemical approach did not achieve statistical significance. A large patient cohort with long term follow-up is required to evaluate the prognostic value of GATA1 expression.

Comparative Evaluation of Multiplex Real-Time PCR Assays for Six Pathogens of Sexually Transmitted Infections / 대한임상미생물학회지

BACKGROUND: The multiplex real-time PCR assay is a sensitive test for simultaneous detection of various pathogens of sexually transmitted infections (STIs). We evaluated the performance of two multiplex real-time PCR assays for six STI pathogens. METHODS: DNA samples after being used to conduct PCR for STI pathogens were stored below −70℃. Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium (MG), Mycoplasma hominis (MH), Ureaplasma urealyticum (UU), and Trichomonas vaginalis (TV) were detected by multiplex real-time PCR with GeneFinder STD I (CT/NG/UU)/II (MG/MH/TV) Multiplex Real-time PCR Kits (Infopia, Korea; GeneFinder assay) and Real-Q CT&NG/MH&TV/MG&UU Kits (BioSewoom, Korea; Real-Q assay). Discrepant results were resolved by another multiplex real-time assay, Anyplex II STI-7 Detection (Seegene, Korea). Any two positive results for the assays were considered true positive. RESULTS: Among 81 samples, the GeneFinder assay detected 63 pathogens from 45 cases (16 CT, 2 NG, 6 MG, 20 MH, 18 UU, and 1 TV) and Real-Q assay detected 66 pathogens from 47 cases (16 CT, 2 NG, 8 MG, 20 MH, 19 UU, and 1 TV). For the results of positive cases and negative cases, the overall concordance rate between the two multiplex real-time assays was 93.8% (Kappa=0.87). For each pathogen, the agreement rates of the two assays ranged from 97.5 to 100% (Kappa>0.8). CONCLUSION: There was no significant difference between the results of GeneFinder assay and Real-Q assay. Both multiplex real-time PCR assays can be useful methods for the detection of STI pathogens in clinical laboratories.

Diagnosis for Imported Cases of Emerging and Reemerging Infectious Diseases in Korea / 이화의대지

Despite recent advances in the development of diagnostics, therapeutics, and vaccines, the ease of international travel and increasing global interdependence have brought about particular challenges for the control of infectious diseases, highlighting concerns for the worldwide spread of emerging and reemerging infectious diseases. Korea is also facing public health challenges for controlling imported cases of infectious diseases; dengue virus, which is the most commonly reported case of imported infectious diseases; the largest outbreak of Middle East respiratory syndrome coronavirus infections outside the Arabian Peninsula in 2015; and the Zika virus infection, which was declared by the WHO as a "Public Health Emergency of International Concern." Although national and global partnerships are critical to controlling imported infectious disease threats, the role of local hospitals, public health sectors, and laboratory capacity remains the cornerstone for initial disease recognition and response. The current status of laboratory diagnosis for imported infectious diseases is reviewed.

Diagnosis for Imported Cases of Emerging and Reemerging Infectious Diseases in Korea / 이화의대지

Despite recent advances in the development of diagnostics, therapeutics, and vaccines, the ease of international travel and increasing global interdependence have brought about particular challenges for the control of infectious diseases, highlighting concerns for the worldwide spread of emerging and reemerging infectious diseases. Korea is also facing public health challenges for controlling imported cases of infectious diseases; dengue virus, which is the most commonly reported case of imported infectious diseases; the largest outbreak of Middle East respiratory syndrome coronavirus infections outside the Arabian Peninsula in 2015; and the Zika virus infection, which was declared by the WHO as a "Public Health Emergency of International Concern." Although national and global partnerships are critical to controlling imported infectious disease threats, the role of local hospitals, public health sectors, and laboratory capacity remains the cornerstone for initial disease recognition and response. The current status of laboratory diagnosis for imported infectious diseases is reviewed.

Effects of Blood Volume Monitoring on the Rate of Positive Blood Cultures from the Emergency Room / 대한임상미생물학회지

BACKGROUND: Blood cultures are essential in diagnosing and treating sepsis. There are several factors that affect the diagnostic yield of blood cultures such as the number of blood sampling episodes, the incubation period, the type and volume of culture media, and the amount of blood drawn. This study aimed to elucidate whether monitoring the volume of blood drawn with an educational intervention could affect the diagnostic quality of blood cultures. METHODS: We implemented quality monitoring for the blood volume drawn during blood culture testing for adults in an emergency room. We instructed the nurses in the emergency room to draw the optimal amount of blood and to reduce the number of blood culture sets from three to two. We analyzed and compared the amount of blood drawn, the rate of positive blood cultures, the contamination rate, and time to positivity (TTP) between 908 patients pre-intervention and 921 patients post-intervention. RESULTS: The amount of blood drawn increased from 0.7±0.3 mL per bottle (pre-intervention) to 6.5±1.7 mL per bottle (post-intervention) (P<0.0001). The rate of positive blood culture post-intervention (12.14%) was higher than that pre-intervention (6.65%) (P<0.0001). The contamination rate post-intervention (1.82%) was also significantly greater than that pre-intervention (0.60%) (P<0.0001). Except for anaerobes, there was no significant difference in the distribution of microorganisms between the pre- and post-intervention periods. The TTP for anaerobe bottles post-intervention was significantly shorter than that of pre-intervention (16.1±16.3 versus 18.6±18.3 h). CONCLUSION: This study suggests that continuing education about adequate blood volume and aseptic techniques is needed to increase the rate of positive blood cultures and reduce the contamination rate of blood cultures.

Two Cases of Medical Device-Related Corynebacterium striatum Infection: A Meningitis and A Sepsis / 대한임상미생물학회지

Corynebacterium striatum is a commonly isolated contaminant in the clinical microbiology. However, it can be an opportunistic pathogen in immunocompromised and even immunocompetent hosts. The increasing prevalence of C. striatum infection has been associated with immunosuppression and prosthetic devices. We report a case of meningitis with cerebrospinal fluid drainage and a case of catheter-related bloodstream infection caused by C. striatum. The isolates were identified as nondiphtherial Corynebacterium species by VITEK 2 (bioMérieux, France) anaerobe and Corynebacterium card. The final identification by 16S rRNA gene sequencing analysis was C. striatum with 99.7% identity and 99.6% identity with C. striatum ATCC 6940, respectively. Both strains were sensitive to vancomycin and gentamicin, but multidrug-resistant to ciprofloxacin, penicillin, erythromycin and imipenem.

Therapeutic Plasma Exchange for a Patient with Severe Cold Agglutinin Disease / 대한수혈학회지

Cold agglutinin disease is a kind of autoimmune hemolytic anemia, caused by cold agglutinin, serum autoantibodies activated at reduced body temperatures to produce red blood cell agglutination and hemolysis. In this paper we described a case of severe hemolytic anemia in a cold agglutinin disease patient treated with therapeutic plasma exchange. Therapeutic plasma exchanges were performed four times every other day. Over the same period, a total of 8 units of washed red blood cells were transfused. Then hemoglobin was increased from 4.0 g/dL to 7.8 g/dL. On the 12th hospital day hemoglobin level was decreased again to 4.2 g/dL and fludarabine chemotherapy was started on the 14th hospital day. The patient's symptoms were relieved and she was discharged on the 30th hospital day. As in this case, therapeutic plasma exchange could be considered as secondary therapy for temporary improvement of acute severe hemolytic anemia in cold agglutinin disease.

Evaluation of the Performance of a New Chromatographic Assay BD Veritor System for Rapid Detection of Influenza A & B / 대한임상미생물학회지

BACKGROUND: For early diagnosis and treatment of influenza, rapid influenza diagnostic tests are commonly used. We evaluated the performance of the BD Veritor System for Rapid Detection of Flu A+B (BD Veritor System; BD Diagnostics, USA) compared to multiplex real-time RT-PCR. METHODS: A total of 3,213 nasal and nasopharyngeal swab specimens in transport media from patients with influenza-like symptoms were tested with the BD Veritor System from December 2013 to April 2014. The sensitivity and specificity of 127 specimens were determined simultaneously using multiplex real-time RT- PCR with the AdvanSure RV real-time PCR (AdvanSure PCR; LG Life Sciences, Korea). RESULTS: Influenza viruses were detected in 41.3% (1,327/3,213) of all specimens tested using the BD Veritor System. Of the 127 specimens, 27 influenza A and 17 influenza B viruses were identified by the AvanSure PCR. The sensitivity and specificity of the BD Veritor System relative to the AdvanSure PCR was 85.2% and 99.0% for influenza A, and 58.8% and 99.1% for influenza B. Of the 190 specimens that tested negative using the BD Veritor System, the AdvanSure PCR detected influenza A and influenza B in 19 and 13 specimens, respectively. The mean threshold cycle (Ct) values of the antigen positive specimens were lower than those of the antigen negative specimens. CONCLUSION: The BD Veritor System showed excellent specificity for both influenza types and good sensitivity for influenza A. However, the system was less sensitive for influenza B compared to multiplex real-time RT-PCR. For accurate diagnosis of false negative specimens, a molecular diagnostic test should be performed. The BD Veritor system could be a useful tool for screening and early diagnosis of influenza.

Clinical and Microbiological Characteristics of Six Staphylococcus pettenkoferi Isolates From Blood Samples

Coagulase-negative staphylococci (CoNS) are reported to be the leading cause of nosocomial bloodstream infections. Staphylococcus pettenkoferi is a novel member of CoNS that was first isolated from the human blood and bursitis wound in 2002. We have reported cases of 6 S. pettenkoferi strains isolated from blood specimens, including one pathogen and 5 contaminants and catheter colonizers. Brucker Biotyper (Brucker Daltonics, Bremen, Germany) and molecular typing with 16S rRNA gene sequencing confirmed the 6 isolates as S. pettenkoferi. The conventional phenotypic identification of these isolates is not reliable owing to their inconsistent biochemical characteristics. Five of the 6 isolates were found to be resistant to oxacillin, and all isolates showed susceptibility to vancomycin and linezolid. For accurate identification of this novel species, advanced methods by using Brucker Biotyper or molecular methods such as 16S rRNA gene sequencing are required.

Establishment and Application of a Multibead Serotyping Assay for Pneumococci in Korea

PURPOSE: Serotyping pneumococcal isolates is important to monitor efficacy of pneumococcal vaccines. Because of difficulties of typing pnueumocci, a multiplex bead-based (multibead) serotyping assay was recently introduced. The aim of this study is to establish a new multibead serotyping assay and to apply this method to analyze clinical isolates of pneumococci in Korea. METHODS: To establish the multibead serotyping assay, six key reagents were transferred from University of Alabama at Birmingham (UAB) to Ewha Center for Vaccine Evaluation and Study (ECVES): bead set coated with polysaccharide and monoclonal antibody pool were used in one multiplex inhibition-type immunoassay and 2 bead sets coated DNA probe and 2 primer pools were used in two multiplex PCR-based assays. After multibead serotyping assay was set up, 75 test samples of pneumococci were analyzed whether ECVES is able to identify serotype correctly. After confirming the performance, serotyping assay was applied to identify serotypes of 528 clinical isolates of pneumococci collected from 3 different hospitals. RESULTS: After establishment of the multibead pneumococcal serotyping assay system at ECVES, 75 test samples were analyzed. There was no discrepancy of serotypes of 75 test samples between the results assigned at UAB and those at ECVES. The serotypes of 528 pneumococci isolated from patients or healthy subjects were determined in 94.3% of isolates (498/528). CONCLUSIONS: The multibead pneumococcal serotyping assay can be successfully established in Korea. With this method, surveillance of serotypes of pneumococci isolated from patients as well as healthy subjects could be studied.

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. The patients were divided into 2 groups according to their target vancomycin trough concentrations: the previous guideline group (n=108) treated with targeted vancomycin trough concentrations of 5-15 mg/L from Jan 2009 through April 2011 and the new guideline group (n=108) treated with targeted concentrations of 15-20 mg/L from November 2011 through July 2012. RESULTS: The 2 groups were not significantly different with respect to age, weight, initial serum creatinine, initial creatinine clearance, predictive trough levels, doses, serum drug concentrations, and area under the curve/minimal inhibitory concentrations. Regarding the proportions of vancomycin trough concentrations, the target range was achieved in 50% in the previous guideline group and in 16% in the new guideline group. In the previous and new guideline groups, the trough concentrations of 10-20 mg/dL were observed in 32.4% and 52.8% patients, respectively, and those of <10 mg/L were observed in 45.4% and 29.6%, respectively. CONCLUSIONS: Compared to the previous guideline group, the new guideline group showed higher proportions in the therapeutic range of 10-20 mg/L and lower proportions in trough concentrations <10 mg/L. The strictly managed vancomycin therapeutic drug monitoring in the new guideline group was assessed as more effective.

Acute Septic Arthritis and Skin Abscess Caused by Neisseria cinerea / 이화의대지

Neisseria cinerea is bacteria known as non-pathogenic strain. However, in rare cases, it can cause opportunistic infections. Those diseases caused by N. cinerea include neonatal ophthalmia, proctitis, pneumonia, peritonitis in patients with continuous ambulatory peritoneal dialysis, endocarditis and meningitis. In this report, we describe a patient with septic arthritis and skin abscess of finger joints that was caused by N. cinerea. A 27-year-old man visited the hospital due to swelling, redness and pain of proximal interphalangeal joint of the left second finger. After blood culture test, ceftriaxone was administered on admission and debridement was performed the affected joints. N. cinerea was identified in the blood culture. The patient was improved with ceftriaxone.