BACKGROUND: The identification of in vitro hemolysis (IVH) using a hematology analyzer is challenging because centrifugation of the specimens cannot be performed for cell counts. In the present study, we aimed to develop a scoring system to help identify the presence of hemolysis in anticoagulated blood specimens. METHODS: Thirty-seven potassium EDTA anticoagulated blood specimens were obtained, and each specimen was divided into 3 aliquots (A, B, and C). Aliquots B and C were mechanically hemolyzed by aspirating 2 and 5 times, respectively, using a 27-gauge needle and then tested; aliquot A was analyzed immediately without any hemolysis. After the cells were counted, aliquots B and C were centrifuged and the supernatants were tested for the hemolytic index and lactate dehydrogenase levels. RESULTS: The 4 hematologic parameters were selected and scored from 0 to 3 as follows:< 34.0, 34.0-36.2, 36.3-38.4, and > or =38.5 for mean cell hemoglobin concentration (MCHC, g/dL); <0.02, 0.02, 0.03, and > or =0.04 for red blood cell ghosts (10(12)/L); <0.13, 0.13-0.38, 0.39-1.30, and > or =1.31 for difference value (g/dL) of measured hemoglobin and calculated hemoglobin; and <0.26, 0.26-0.95, 0.96-3.34, and > or =3.35 for difference value (g/dL) of MCHC and cell hemoglobin concentration mean. The hemolysis score was calculated by adding all the scores from the 4 parameters. At the cutoff hemolysis score of 3, the IVH of aliquots B and C were detected as 64.9% and 91.9%, respectively. CONCLUSIONS: The scoring system might provide effective screening for detecting spurious IVH.
Anticoagulants/*pharmacology ; *Blood Specimen Collection ; Edetic Acid/pharmacology ; Hemoglobins/analysis ; Hemolysis/drug effects ; Humans

A total of 1,132 pleural fluid culture results obtained from October 2012 to July 2014 were analyzed to elucidate the microbiological characteristics according to transudative and exudative pleural fluid. The pleural fluid cultures were performed using aerobic and anaerobic blood culture bottles. The blood and pleural fluid for total protein, lactate dehydrogenase, and glucose measurement were submitted to laboratory at the same time with pleural fluid cultures. The rates for culture positivity, anaerobes isolation, and polymicrobials between transudative and exudative pleural fluid were 5.2% vs. 10.4%, 14.8% vs. 7.8%, and 14.8% vs. 10.9%.
Exudates and Transudates ; Glucose ; L-Lactate Dehydrogenase

BACKGROUND: The false positive signals of a continuous monitoring blood culture system (CMBCS) increase the reporting time and laboratory cost. This study aimed to determine the highly relevant variables that discriminate false positive signals from true positive signals in a CMBCS. METHODS: Among 184,363 blood culture sets (aerobic and anaerobic), the signal-positive samples according to a BACTEC FX system (Plus Aerobic/F, BDA; Plus Anaerobic/F, BDN) and BacT/Alert 3D system (Standard Aerobic, BSA; Standard Anaerobic, BSN) between April 2010 and November 2013 were classified into two groups: false positive or true positive signals. The data of 15 parameters between the two groups were then statistically compared. RESULTS: Among total blood cultures, the positive rates of CMBCS signals according to BDA, BDN, BSA, and BSN were 4.9%, 2.8%, 3.8%, and 3.2%, respectively. The false positive rates of CMBCS signals according to BDA, BDN, BSA, and BSN were 0.6%, 0.1%, 0.1%, and 0.1%, respectively. The blood volume, detection time, time interval between admission and test, C-reactive protein concentration, leukocyte count, delta neutrophil index, and mean peroxidase index showed statistically significant differences between the two groups. CONCLUSION: There were no variables with diagnostic sensitivity and specificity for discriminating the two groups. Therefore, analysis of bacterial growth curves produced by CMBCS is needed for early and effective detection of false positive signals.
Blood Volume ; C-Reactive Protein ; Leukocyte Count ; Neutrophils ; Peroxidase

No abstract available.
Aged ; Anti-Bacterial Agents/therapeutic use ; Bursitis/*diagnosis/drug therapy/microbiology ; Cefoperazone/therapeutic use ; Diabetes Mellitus, Type 2/complications/*diagnosis ; Humans ; Male ; Nocardia/genetics/*isolation & purification ; Polymerase Chain Reaction ; RNA, Ribosomal, 16S/chemistry/genetics ; Sequence Analysis, RNA ; Sulbactam/therapeutic use

BACKGROUND: This study aimed to evaluate the prevalence of Mycoplasma pneumoniae in primary and tertiary care hospitals and its macrolide resistance rate. METHODS: Nasopharyngeal swabs were collected from 195 pediatric patients in primary and tertiary care hospitals from October to November 2010. The AccuPower MP real-time PCR kit (Bioneer, Korea) was used for the detection of M. pneumoniae. Direct amplicon sequencing was performed to detect point mutations conferring resistance to macrolides in the 23S rRNA gene. RESULTS: Among the 195 specimens, 17 (8.7%) were M. pneumoniae positive, and 3 of the strains (17.6%) obtained from these 17 specimens displayed the A2063G mutation in 23S rRNA. Three macrolide-resistant M. pneumoniae isolates were isolated from patients hospitalized at the primary care hospital. The positive rates of M. pneumoniae for the primary and tertiary care hospitals were 12.1% (15/124) and 2.8% (2/71), respectively (P=0.033). CONCLUSIONS: The positive rate of M. pneumoniae in the primary care hospital was higher than that in the tertiary care hospital. Simultaneous detection of M. pneumoniae and macrolide-resistant mutation genes in the 23S rRNA by real-time PCR is needed for rapid diagnosis and therapy of M. pneumoniae infections.
Anti-Bacterial Agents/*pharmacology ; Child, Preschool ; Drug Resistance, Bacterial/*drug effects ; Female ; Humans ; Infant ; Infant, Newborn ; Macrolides/*pharmacology ; Male ; Mycoplasma pneumoniae/genetics/*isolation & purification ; Nasopharynx/microbiology ; Pneumonia, Mycoplasma/epidemiology/microbiology ; Primary Health Care ; RNA, Ribosomal, 23S/analysis ; Reagent Kits, Diagnostic ; Real-Time Polymerase Chain Reaction ; Tertiary Healthcare

BACKGROUND: In order to determine the clinical usefulness of the MicroScan (Siemens Healthcare Diagnostics, USA) MICroSTREP plus antimicrobial panel (MICroSTREP) for testing antimicrobial susceptibility of beta-hemolytic streptococci (BHS) and viridans group streptococci (VGS), we compared the accuracy of MICroSTREP with that of the CLSI reference method. METHODS: Seventy-five BHS and 59 VGS isolates were tested for antimicrobial susceptibility to ampicillin, penicillin, cefotaxime, meropenem, erythromycin, clindamycin, levofloxacin, and vancomycin by using MICroSTREP and the CLSI agar dilution method. RESULTS: The overall essential agreement with regard to minimum inhibitory concentrations (MICs) (within +/-1 double dilution) between MICroSTREP and the CLSI reference method was 98.2%, and categorical agreement (CA) was 96.9%. For the BHS isolates, the CA for erythromycin was 96.0%, whereas that for cefotaxime, meropenem, levofloxacin, and vancomycin (for ampicillin, penicillin, and clindamycin; 98.7%) was 100%. For the VGS isolates, the CA for penicillin was 84.7% and that for erythromycin, clindamycin, and vancomycin (for meropenem, 86.5%; for ampicillin, 88.1%; and for cefotaxime and levofloxacin, 96.6%) was 100%. All categorical errors of penicillin and ampicillin in the VGS isolates were minor. CONCLUSIONS: The accuracy of MICroSTREP is comparable to that of the CLSI reference method, suggesting that this panel can be effective for testing antimicrobial susceptibility of BHS and VGS.
Anti-Bacterial Agents/*pharmacology ; Drug Resistance, Bacterial ; Humans ; Microbial Sensitivity Tests ; Reagent Kits, Diagnostic ; Streptococcal Infections/microbiology ; Streptococcus/*drug effects/isolation & purification ; Viridans Streptococci/*drug effects/isolation & purification

BACKGROUND: The VITEK-2 yeast susceptibility test (AST-YS01; bioMerieux, Hazelwood, MO, USA) has recently been introduced as a fully automated, commercial antifungal susceptibility test system that determines MIC endpoints spectrophotometrically, thereby eliminating subjective errors. We compared the ATB FUNGUS 2 (bioMerieux) and VITEK-2 (AST-YS01) systems to the CLSI M27 method for susceptibility testing of Candida isolates. METHODS: We tested 59 Candida species that were isolated from blood cultures at Wonju Christian Hospital between September 2008 and August 2009. We compared MIC results for amphotericin B, flucytosine, fluconazole and voriconazole using the ATB FUNGUS 2 and VITEK-2 (AST-YS01) tests to those obtained by the CLSI M27 broth microdilution method. RESULTS: Within two-fold dilutions of MICs, the agreement of the ATB FUNGUS 2 and VITEK-2 (AST-YS01) tests with the CLSI method according to antifungal agents were: amphotericin B, 100% vs. 100% flucytosine, 100% vs. 100% fluconazole, 83.6% vs. 98.3% and voriconazole, 83.6% vs. 96.7%, respectively. The categorical discrepancies for fluconazole and voriconazole were 20.4% and 18.6% for ATB FUNGUS 2, and 6.8% and 0% for VITEK-2 (ASTYS01). There were no major errors for fluconazole and voriconazole in either ATB FUNGUS 2 or VITEK-2 (AST-YS01) tests. CONCLUSION: The VITEK-2 system (AST-YS01) appears to be rapid and highly correlative with the CLSI method, suggesting that it is effective for antifungal susceptibility testing for Candida species in clinical settings.
Amphotericin B ; Antifungal Agents ; Candida ; Fluconazole ; Flucytosine ; Fungi ; Pyrimidines ; Triazoles ; Yeasts

BACKGROUND: Accurate detection of organisms producing extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase is very important for treatment of patients. However, unlike the ESBL confirmatory test, there are no guidelines for detection of organisms producing AmpC beta-lactamase. We evaluated a detection method using boronic acid (BA) for ESBL and AmpC beta-lactamase. METHODS: Clinical isolates of Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, and Proteus mirabilis showing intermediate resistance or resistance to cefoxitin (FOX) or positive for ESBL were tested. A > or =5 mm increase in zone diameter of ceftazidime/clavulanic acid/BA (CAZ/CA/BA) and/or cefotaxime/clavulanic acid/BA (CTX/CA/BA) versus CAZ/BA and/or CTX /BA was considered positive for ESBL. Likewise, a > or =5 mm increase in zone diameter of FOX/BA and/or cefotetan/BA (CTT/BA) versus FOX and/or CTT alone was considered positive for AmpC beta-lactamase. RESULTS: Among 622 clinical isolates, ESBL positive rates by the CLSI ESBL confirmatory test or by the BA method were 18.1% or 18.4% for E. coli, 38.3% or 40.4% for K. pneumoniae, 8.7% or 8.7% for K. oxytoca, and 14.8% or 14.8% for P. mirabilis, respectively. AmpC beta-lactamase positive rates using the BA method were 3.7% for E. coli, 33.3% for K. pneumoniae, 0% for K. oxytoca, and 7.4% for P. mirabilis. The detection rates of coproducing ESBL and AmpC beta-lactamase were 2.4% in E. coli 27.1% in K. pneumoniae, and 3.7% in P. mirabilis. CONCLUSION: The ESBL confirmatory method using BA was found to enhance the detection of ESBLs, even when potentially masked by AmpC beta-lactamase.
Bacterial Proteins ; beta-Lactamases ; Boron ; Cefoxitin ; Escherichia ; Escherichia coli ; Humans ; Klebsiella ; Klebsiella oxytoca ; Klebsiella pneumoniae ; Masks ; Mirabilis ; Penicillinase ; Pneumonia ; Proteus ; Proteus mirabilis

Rothia dentocariosa, a pleomorphic gram-positive branching bacillus, is a common inhabitant of the nose and throat. It is a well-known causative agent of dental plaques and periodontal diseases. Although generally regarded as having a low virulence to humans, R. dentocariosa has been recognized as causative agents of infective endocarditis and bacteremia with increasing frequency. Consequently, it can be a very serious pathogen when isolated from usually sterile sites such as blood or cerebrospinal fluid. We report a case of Rothia dentocariosa bacteremia without endocarditis in a 17-month-old male patient with fever, vomiting and diarrhea.
Bacillus ; Bacteremia ; Endocarditis ; Fever ; Humans ; Infant ; Male ; Nose ; Periodontal Diseases ; Pharynx ; Vomiting

Pasteurella dagmatis is an oxidase and catalase positive, facultative anaerobic, gram-negative coccobacillus classified as a member of the family Pasteurellaceae. Pasteurella species are commonly colonizing the oropharynx of healthy domestic and wild animals including cats and dogs. These are usually pathogenic to domestic animals, but rarely to human beings. Pasteurella infection of human causes pneumonia, empyema, meningitis, peritonitis, bone and joint infection and septicemia. Recently, we experienced a case of dog-bite wounds from which Pasteurella dagmatis was isolated in a 39-year-old woman. To our knowledge, this is the first report of Pasteurella dagmatis isolated from dog-bite wounds in Korea.
Adult ; Animals ; Animals, Domestic ; Animals, Wild ; Catalase ; Cats ; Colon ; Dogs ; Empyema ; Female ; Humans ; Joints ; Korea ; Meningitis ; Oropharynx ; Oxidoreductases ; Pasteurella Infections ; Pasteurella* ; Pasteurellaceae ; Peritonitis ; Pneumonia ; Sepsis ; Wounds and Injuries*