BACKGROUND: Previously considered as nonpathogenic contaminants, coagulase-negative staphylococci (CoNS) are now a major cause of nosocomial infections as increased use of prosthetic devices, intravascular catheters, and other invasive technology in more immunosuppressed patients and urinary tract infections (UTI) due to CoNS have been reported. In present study, species frequency, antimicrobial susceptability and clinical characteristics of CoNS UTI were evaluated. METHOD: We performed species identification and antimicrobial susceptibility of 109 CoNS strains isolated from urine in Ewha Womans University hospital from January 1998 to December 2002 and analysed clinical characteristics of 57 cases with CoNS UTI cases, retrospectively. RESULTS: Among 13,336 strains isolated from urine, 109 strains were CoNS showing 0.8%. The most common species of CoNS from urine were S. epidermidis (49.5%) followed by S. haemolyticus (16.5%), S. saprophyticus (13.8%), S. auricularis (1.8%), S. simulans (0.9%) and unidentified CoNS represented 17.4%. The antimicrobial susceptibility showed high resistance to multiple drugs. Among CoNS, S. haemolyticus showed the highest resistance whereas S. saprophyticus showed the highest susceptibility to multiple drugs. The patients isolated S. saprophyticus were younger (mean age: 41 yrs) than those isolated other CoNS (mean age: 53 yrs) and more frequently female (9/14 vs 19/43). The hospitalized patients (74.4% vs 21.4%), bacteriuria more than 10 5 CFU/ml (83.7% vs 64.3%), indwelling catheter (34.9% vs 7.1%) and other risk factors (48.8% vs 35.7%) were more common in patients isolated other CoNS than those isolated S. saprophyticus and no significant differences were noted in pyuria (51.2% vs 57.1%). The symptomatic presentations were more common in patients isolated S. saprophyticus than those isolated other CoNS (71.4% vs 9.3%) and so were treatment (85.7% vs 44.2%). CONCLUSIONS: When CoNS other than S. saprophyticus isolated from urine in hospitalized patientes with risk factors, identification and antimicrobial susceptability test is necessary for proper management.
Bacteriuria ; Catheters ; Catheters, Indwelling ; Cross Infection ; Female ; Humans ; Pyuria ; Retrospective Studies ; Risk Factors ; Urinary Tract Infections* ; Urinary Tract*

Staphylococcus lugdunensis is a member of the coagulase negative staphylococci (CoNS) which has been associated with serious infections in humans. Species identification of S. lugdunensis isolates should be done but they may be misidentified as other CoNS species or Staphylococcus aureus due to positivity for clumping factor. We report the first two cases of catalase-positive and Gram positive cocci isolated from blood and venous catheter, which were positive for latex agglutination coagulase test but susceptible to penicillin, negative for tube coagulase test and negative acid production from mannitol and finally identified as S. lugdunensis.
Agglutination ; Catheters* ; Coagulase ; Gram-Positive Cocci ; Humans ; Latex ; Mannitol ; Penicillins ; Staphylococcus aureus ; Staphylococcus lugdunensis

BACKGROUND: Acinetobacter baumannii has been reported as a major cause of nosocomial infections with increasing frequency. Recently, the emergence of carbapenem-resistant strains has become a major problem in treatment. The use of nontraditional agents such as colistin and a combination therapy have been tried. The purpose of this study was to evaluate the activity of antimicrobial combinations against multidrug-resistant (MDR) A. baumannii. METHODS: Twenty-nine strains of MDR A. baumannii, either resistant or intermediate to imipenem, were collected from February 2003 to February 2004. Minimum inhibitory concentrations (MICs) were determined by the agar dilution method. The checkerboard method was used to assess the activity of ampicillin-sulbactam in combination with amikacin, tobramycin or meropenem and colistin in combination with ceftazidime, meropenem, or rifampin. RESULTS: The MIC90 of ceftazidime and cefepime were 2, 048 g/mL and 512 g/mL, respectively, while the MIC90 of colistin was 0.5 g/mL. The antimicrobial combinations that showed an additive effect for one or two strains were colistin with rifampin or ceftazidime and ampicillin-sulbactam with tobramycin or meropenem. Other antimicrobial combinations showed indifferent effects against most strains. There were no synergistic or antagonistic combinations. CONCLUSIONS: These data suggested that colistin may be an alternative drug for MDR A. baumannii. For the effective treatment of patients infected with these resistant strains, further studies are needed to evaluate antimicrobial combinations against a large number of heterogeneous isolates, and these studies must be followed by clinical trials.
Acinetobacter baumannii* ; Agar ; Amikacin ; Ceftazidime ; Colistin ; Cross Infection ; Humans ; Imipenem ; Microbial Sensitivity Tests ; Rifampin ; Tobramycin

Background: Dengue fever is considered one of the transfusion-transmissible emerging infectious diseases. Dengue fever has been reported every year by the Korea Disease Control and Prevention Agency (KDCA). Because a blood donor screening assay to detect the dengue virus (DENV) as an agent of dengue fever is not performed, the risk of transfusion-transmitted DENV infection needs to be assessed. Methods: This study collected the data of DENV infected cases from the Infectious Disease Portal of the KDCA, the data of blood donors and blood components from the Blood Information Management System of the Korean Red Cross, and the data of travelers to major dengue outbreak countries from the Korean Tourism Organization.All data were from 2016 to 2018. A risk assessment was performed using European Up-Front Risk Assessment Tool (EUFRAT). Results: The risk of DENV-infected red cells and platelet concentrate was higher than that of plasma and apheresis platelet. Nevertheless, the risk of the DENV infected blood component was shown to be less than one case per year for all kinds of blood components. Conclusion All the DENV infected cases in Korea were overseas travelers. Therefore, the risk of transfusiontransmissible DENV infection is very low. On the other hand, continuous observation and monitoring are required because Aedes albopictus as a vector of DENV is found in Korea, and the increase in reported cases may lead to domestic infections.

Background: Dengue fever is considered one of the transfusion-transmissible emerging infectious diseases. Dengue fever has been reported every year by the Korea Disease Control and Prevention Agency (KDCA). Because a blood donor screening assay to detect the dengue virus (DENV) as an agent of dengue fever is not performed, the risk of transfusion-transmitted DENV infection needs to be assessed. Methods: This study collected the data of DENV infected cases from the Infectious Disease Portal of the KDCA, the data of blood donors and blood components from the Blood Information Management System of the Korean Red Cross, and the data of travelers to major dengue outbreak countries from the Korean Tourism Organization.All data were from 2016 to 2018. A risk assessment was performed using European Up-Front Risk Assessment Tool (EUFRAT). Results: The risk of DENV-infected red cells and platelet concentrate was higher than that of plasma and apheresis platelet. Nevertheless, the risk of the DENV infected blood component was shown to be less than one case per year for all kinds of blood components. Conclusion All the DENV infected cases in Korea were overseas travelers. Therefore, the risk of transfusiontransmissible DENV infection is very low. On the other hand, continuous observation and monitoring are required because Aedes albopictus as a vector of DENV is found in Korea, and the increase in reported cases may lead to domestic infections.

BACKGROUND: Despite the diagnostic utility of immunophenotyping for myelodysplastic syndromes (MDS), it has not been widely performed, and reports on this are absent in Korea. We aimed to evaluate the immunophenotypic features of non-blastic granulocytes, monocytes, and blasts in patients with MDS and non-clonal disorders using routine flow cytometry (FCM). Moreover, we evaluated the phenotypic abnormalities of mature cells in leukemic patients. METHODS: Marrow aspirates from 60 patients, including 18 with MDS, 18 with leukemia, and 24 with non-clonal disorders (control group), were analyzed using FCM. Blasts, non-blast myeloid cells, and monocytes were gated based on CD45 expression and side scatter (SSC). The phenotypes were then compared among the 3 groups. RESULTS: Compared to non-clonal disorders, the granulocytic lineages of MDS showed decreased SSC (P=0.005), increased CD45 intensity (P=0.020), decreased CD10-positive granulocytes (P= 0.030), and a higher CD56-positive rate (P=0.005). It is noteworthy that similar results were obtained in the leukemia group, and these findings were not related to the phenotypes of the leukemic cells. Using blast and monocytic gating, useful parameters for generating a differential diagnosis were not found. CONCLUSIONS: Gating the granulocytic region is a relatively easy method for MDS immunophenotyping. Among the parameters studied, SSC, CD10, and CD56 were the most useful for differentiating MDS from non-clonal disorders. While immunophenotypic changes in MDS appear to be useful for differentiating MDS from non-clonal disorders, these changes were also noted in the mature cells of leukemic patients.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antigens, CD45/metabolism ; Antigens, CD56/metabolism ; Bone Marrow Cells/cytology ; Cell Lineage ; Child ; Child, Preschool ; Diagnosis, Differential ; Female ; Flow Cytometry ; Granulocytes/*classification ; Humans ; *Immunophenotyping ; Leukemia/diagnosis/pathology ; Male ; Middle Aged ; Monocytes/*classification ; Myelodysplastic Syndromes/*diagnosis ; Neprilysin/metabolism ; Phenotype

Background: The Korean Red Cross adopted HIV NAT for blood donor screening in 2005 using a minipool assay. In June 2012, the NAT system was replaced with the individual assay. This study examined the characteristics of HIV NAT reactive blood donors to determine if there was any difference in their features between 10 years ago and later. Methods: This study analyzed the HIV RNA quantitative values and the distribution of HIV subtypes using 118 HIV NAT positive blood donations (37 in 2007, 20 in 2008, 32 in 2017 and 29 in 2018). Results: No significant variations of the quantitative values of HIV RNA and the distribution of HIV subtypes 10 years ago and later were observed. This study failed to produce quantitative values of three samples due to the low titer. The mean titer of HIV RNA of the remaining 115 samples were 5.14×10 4 IU/mL. The dominant HIV subtype of the HIV NAT reactive donors was B showing 54.2% (64/118). Approximately 5.9% (7/118) of the samples showed the HIV subtype C. Forty-seven samples (39.8%) showed the circulating recombinant form (CRF). Conclusion The rate of HIV subtype B in this study (54.2%) has decreased compared to the results of the past study (95.2%). Some of the cases showing CRF were identified as B in the past study because CRF3, 8, 9, 14, and 15 are recombinant forms, including subtype B.

BACKGROUND: Recently our institution noted a marked increase in the number of Extended-Spectrum beta-Lactamase(ESBL)-producing Escherichia coli isolated from children with urinary tract infections (UTI). The purpose of this study was to investigate frequency, risk factors and outcomes for pediatric UTI due to ESBL-producing E. coli. METHODS: We analyzed 27 children with UTI due to ESBL-producing E. coli (cases) and 27 children with UTI due to non-ESBL-producing E. coli (controls) in Ewha Womans University Hospital from July to December 2001. RESULTS: Of the total 434 E. coli isolates from urine, 32 (7.4%) produced ESBL and the prevalence of UTI due to ESBL-producing E. coli was higher in children (15.2%) than in adults (2.0%). Case patients had higher resistances to ampicillin/sulbactam, aztreonam, cefazolin, ceftriaxone, gentamicin, tobramycin, TMP-SXT and piperacillin/tazobactam than controls. No significant differences were noted in resistance to amikacin, ampicillin, cefoxitin, ciprofloxacin and imipenem (P>0.05). Case patients were younger and more frequently male than control patients. No significant differences were noted in prior UTI, prior antibiotic use, genitourinary abnormality, vesicoureteral reflux, urinary catheter, pyelonephritis or underlying diseases (P>0.05). No significant difference in cure rate was noted between both groups, but case patients had a significantly higher relapse (11/27) than control patients (1/27) (P<0.05). CONCLUSIONS: ESBL-producing E. coli may be a causative agent of UTI in children without any specific risk factors. To eradicate ESBL-producing strains, new guidelines of detection and antibiotic therapy for pediatric UTI may be necessary through more evaluation.
Adult ; Amikacin ; Ampicillin ; Aztreonam ; Cefazolin ; Cefoxitin ; Ceftriaxone ; Child* ; Ciprofloxacin ; Escherichia coli* ; Escherichia* ; Female ; Gentamicins ; Humans ; Imipenem ; Male ; Prevalence ; Pyelonephritis ; Recurrence ; Risk Factors* ; Tobramycin ; Urinary Catheters ; Urinary Tract Infections* ; Urinary Tract* ; Urogenital Abnormalities ; Vesico-Ureteral Reflux

OBJECTIVE: The purpose of this study was to compare the precision of three-dimensional (3D) images acquired using iTero(R) (Align Technology Inc., San Jose, CA, USA) and Trios(R) (3Shape Dental Systems, Copenhagen, Denmark) digital intraoral scanners, and to evaluate the effects of the severity of tooth irregularities and scanning sequence on precision. METHODS: Dental arch models were fabricated with differing degrees of tooth irregularity and divided into 2 groups based on scanning sequence. To assess their precision, images were superimposed and an optimized superimposition algorithm was employed to measure any 3D deviation. The t-test, paired t-test, and one-way ANOVA were performed (p < 0.05) for statistical analysis. RESULTS: The iTero(R) and Trios(R) systems showed no statistically significant difference in precision among models with differing degrees of tooth irregularity. However, there were statistically significant differences in the precision of the 2 scanners when the starting points of scanning were different. The iTero(R) scanner (mean deviation, 29.84 +/- 12.08 microm) proved to be less precise than the Trios(R) scanner (22.17 +/- 4.47 microm). CONCLUSIONS: The precision of 3D images differed according to the degree of tooth irregularity, scanning sequence, and scanner type. However, from a clinical standpoint, both scanners were highly accurate regardless of the degree of tooth irregularity.
Dental Arch ; Imaging, Three-Dimensional* ; Tooth*

BACKGROUND: The test for the anti-rubella IgM Ab (R-IgM) is important in early pregnancies because therapeutic termination may be considered depending on the results. METHODS: The subjects consisted of 52 pregnant women with positive or equivocal R-IgM by Cobas Core Anti-Rubella IgM EIA test (Roche, Basel, Swiss) between January 1997 and July 2000. Three different EIA methods such as the Enzygnost Anti-Rubella-virus/IgM test (DADE Behring, Marburg, Germany), the AxSYM Anti-Rubella IgM test (Abbott, USA), and the IMx Anti-Rubella IgM test (Abbott, USA) were simultaneously performed on 44 specimens as well as the Cobas Core Anti-Rubella IgM EIA test. RESULTS: Among 52 pregnancies, 9 (17%) experienced an artificial abortion due to positive or equivocal R-IgM result. The clinical symptoms associated with rubella infection were observed in 3 cases and the persistent R-IgM positivity was noted for more than 1 year in 4 cases. The concordance rate between 4 different EIAs was 41%. When performed with serial diluted pool and 3 sera, the results of Cobas Core were similar to those of AxSYM, IMx and Enzygnost. The R-IgM were detected one titre higher in diluted sera performed by IMx and Enzygnost than those of Cobas Core and AxSYM. CONCLUSIONS: For pregnancies with positive or equivocal R-IgM, it is recommended that results should be interpreted with caution, considering the possibilities, such as a persistent R-IgM response and discrepant R-IgM depending on the different EIA methods.
Female ; Humans ; Immunoenzyme Techniques* ; Immunoglobulin M* ; Pregnancy* ; Pregnant Women ; Rubella