Two trials of external quality assessment for clinical microbiology laboratories were performed in 2009. A total of 16 specimens were distributed. Eight specimens were distributed to 339 laboratories with 322 (95.0%) returns in Trial I, and another eight specimens to 337 laboratories with 327 returns (97.0%) in Trial II. Two slide specimens for mycobacterium stain (AFB) were distributed in both Trial I and II. The acceptable percentages of Gram stain were relatively good for both stainability and morphology. The acceptable percentages of bacterial identification (correct answers to species level) on Sterotrophomonas maltophilia, Staphylococcus aureus, Streptococcus agalactiae, Micrococcus luteus, Vibrio parahemolyticus and Candida glabrata (Trial I) were 94.4%, 98.5%, 92.1%, 62.3%, 92.1% and 71.5%, respectively. The acceptable percentages of bacterial identification on Pseudomonas aeruginosa, Enterococcus faecalis, Candida albicans, Staphylococcus epidermidis, Moraxella catarrhalis and Enterobacter cloacae (Trial II) were 98.5%, 94.1%, 89.2%, 86.2%, 79.6% and 98.5%, respectively. The acceptable percentages for antimicrobial susceptibility tests on S. maltophilia and S. aureus (Trial I), and P. aeruginosa and E. faecalis(Trial II) were relatively good compared to data of the last year, except results using disk method for S. maltophilia. The acceptable percentages for AFB stain in Trial I and II were relatively high. In summary, the acceptable percentages of bacterial stain and identification were relatively good. However, it is still necessary that the quality assurance of the individual laboratories should be improved for antimicrobial susceptibility tests, and the selection of the most appropriate antimicrobial agents to test should be also considered.
Anti-Infective Agents ; Candida albicans ; Candida glabrata ; Enterobacter cloacae ; Enterococcus faecalis ; Korea ; Micrococcus luteus ; Moraxella (Branhamella) catarrhalis ; Mycobacterium ; Pseudomonas aeruginosa ; Staphylococcus aureus ; Staphylococcus epidermidis ; Streptococcus agalactiae ; Vibrio

BACKGROUND: Viridans group streptococci (VGS) are being increasingly reported as pathogens causing septicemia in neutropenic and other immunocompromised patients since 1980s. In the past, VGS were nearly uniformly susceptible to beta-lactam antimicrobial agents, aminoglycosides, tetracyclines, and macrolides. Several recent published studies, however, indicate that antimicrobial resistance may be emerging as a problem with VGS. The purpose of this study was to determine the antimicrobial susceptibility of VGS strains isolated from blood cultures in recent period. METHODS: A total of 45 consecutive strains of VGS isolated from blood cultures between May 2001 and March 2002 at Wonju Christian Hospital were tested for antimicrobial susceptibility. Identification of VGS were performed by API Strep 32(bioMerieux sa, Marcy-l'Etoile, France) commercial kit. Antimicrobial susceptibility tests were done by NCCLS recommended disk diffusion method and penicillin MICs were determined by E test. RESULTS: Among the 45 VGS strains, frequently isolated organisms were Streptococcus mitis (31.1%), Streptococcus oralis (17.8%), Streptococcus constellatus (11.1%), and Streptococcus anginosus (8.9%). Overall intermediate-and resistant rates to antimicrobial agents of VGS were as follows: penicillin; 26.7% and 8.9%, erythromycin; 4.4% and 28.9%, clindamycin 2.2% and 22.2%, and ceftriaxone; 4.4% and 6.7%, respectively. Resistant rates of Streptococcus mitis and Streptococcus oralis were as follows: penicillin; 50% vs 50%, erythromycin 43% vs 37%, clindamycin 21% vs 37%, and ceftriaxone 7% vs 25%, respectively. CONCLUSIONS: These results indicate the species-related variability of susceptibility among VGS isolated from blood in recent period. In addition to S. mitis, S. oralis also displayed high rates of resistance to penicillin, macrolides, and ceftriaxone. The difference in susceptibilities between species of VGS indicates the importance of accurate identification and the need for continuing monitoring of antimicrobial resistance.
Aminoglycosides ; Anti-Infective Agents ; Ceftriaxone ; Clindamycin ; Diffusion ; Erythromycin ; Gangwon-do ; Immunocompromised Host ; Macrolides ; Penicillin Resistance ; Penicillins ; Sepsis ; Streptococcus anginosus ; Streptococcus constellatus ; Streptococcus mitis ; Streptococcus oralis ; Tetracyclines ; Viridans Streptococci*

Widespread development of antimicrobial resistance by major bacterial pathogens including Staphylococcus aureus, Streptococcus pneumoniae, Enterococci, and gram-negative bacilli have emerged as a global healthcare concern. Antimicrobial resistance was first identified during the 1940s and 50s with penicillin resistance in S. aureus. During the 1970s and 80s, methicillin-resistant S. aureus (MRSA) rapidly emerged as a major nosocomial pathogen in hospitals throughout the world. In the 1990s, a variation of MRSA emerged as community-associated MRSA (CA-MRSA), which is contracted outside of the hospital setting, and has become one of the most common pathogens associated with skin and skin structure infections in the United States and other parts of the world. Vancomycin-intermediate S. aureus (VISA) was first reported in 1996, and high-level vancomycin-resistant S. aureus (VRSA) was reported in 2002. S. pneumoniae has demonstrated a significant increase in resistance to macrolides and beta-lactam agents since 1980s, particularly in Asian countries while penicillin resistance is not prevalent among non-meningeal isolates according to the new breakpoints from CLSI. Vancomycin resistant enterococci, particularly E. faecium, is a major concern associated with nosocomial infections in many hospitals. Given the widespread emergence and spread of antimicrobial resistant gram-positive cocci during recent decades, the problem is likely to continue to increase as a critical, clinical problem.
Asian Continental Ancestry Group ; Contracts ; Cross Infection ; Delivery of Health Care ; Gram-Positive Cocci ; Humans ; Macrolides ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Penicillin Resistance ; Pneumonia ; Skin ; Staphylococcus aureus ; Streptococcus pneumoniae ; United States ; Vancomycin

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

Staphylococcus aureus bacteremia is associated with high mortality and morbidity, requiring prompt and appropriate antimicrobial treatment. Therefore, it is important to detect methicillin-resistant S. aureus (MRSA) rapidly from blood cultures. Two immunochromatographic tests, BinaxNow S. aureus and BinaxNow PBP2a, were directly applied to 79 Bact/Alert bottles that were positive for Gram positive cocci in cluster aggregations. Sensitivity and specificity for the identification of S. aureus and determination of methicillin resistance were 94% and 87%, and 100% and 100%, respectively, with less than 30 min of performance time. These tests are efficient and rapid; these tests are valuable alternatives to more sophisticated and expensive methods used in the diagnosis of MRSA bacteremia.
Bacteremia ; Diagnosis ; Gram-Positive Cocci ; Methicillin Resistance ; Methicillin* ; Methicillin-Resistant Staphylococcus aureus ; Mortality ; Staphylococcus aureus*

Infective endocarditis is the infectious disease that produces vegetation on endocardium. Acute bacterial endocarditis is most frequently caused by Staphylococcus aureus, occurs on a normal heart valve, and subacute endocarditis usually caused by Streptococcus viridans occurs on damaged valves. Gemella haemolysans are gram-positive cocci that is placed in the family Streptococcaceae. As opportunistic pathogen, Gemella haemolysans are able to cause severe localized and generalized infections and it is known that this organism very rarely causes infective endocarditis. The paucity of reports concerning Gemella haemolysans is probably related to the difficulties associated with their identification. Several laboratory tests to prevent misinterpretation of this organism are now suggested. We have experienced a case of infective endocarditis that is caused by Gemella haemolysans in 37 year old male patient with ventricular septal defect. Gemella haemolysans were detected by blood culture and he was treated with intravenous vancomycin with gentamicin and ceftriaxone, and also underwent cardiac surgery. This is the first case of Gemella haemolysans endocarditis of ventricular septal defect in Korea.
Adult ; Ceftriaxone ; Communicable Diseases ; Endocarditis* ; Endocarditis, Bacterial ; Endocardium ; Gemella* ; Gentamicins ; Gram-Positive Cocci ; Heart Septal Defects, Ventricular* ; Heart Valves ; Humans ; Korea ; Male ; Staphylococcus aureus ; Streptococcaceae ; Thoracic Surgery ; Vancomycin ; Viridans Streptococci

BACKGROUND: Blood culture is an important method for identifying infectious microorganisms and confirming that a selected antimicrobial treatment is appropriate. In this study, we investigated the annual changes in the frequencies of blood isolates and antibiotic susceptibility test (AST) results. METHODS: We created a large database comprising data on all patient-unique blood cultures obtained from January 2007 through December 2016. Blood specimens were cultured using the BD BACTEC FX system, and species identification and AST were performed using the VITEK 2 system. RESULTS: During the 10-year study period, a total of 203,651 blood culture results were collected. Of these, gram-positive cocci, gram-negative rods, and fungi were isolated in 2.15%, 0.55%, and 0.12% of the blood cultures, respectively. Escherichia coli was the most commonly isolated species (22.8%), followed by Staphylococcus epidermidis (16.8%), Klebsiella pneumoniae (8.1%), and Staphylococcus aureus (8.0%). Fungal species were isolated in 3.0% of all positive blood cultures. Candida albicans was the most commonly isolated species (1.1%), followed by Candida parapsilosis (0.6%). Methicillin resistance was seen in 55.2% of S. aureus isolates. The frequencies of vancomycin-resistant Enterococcus (VRE) and carbapenem-resistant Pseudomonas aeruginosa (CRPA) were 13.1% and 10.9%, respectively. The isolation rates of MRSA, VRE, and CRPA showed different patterns each year. CONCLUSIONS: Among the isolates, E. coli was the most common, followed by S. epidermidis and K. pneumoniae. This study represents a long-term analysis of bloodstream infections, and the results can be used to identify trends in the microorganisms isolated and their drug resistance.
Bacteremia ; Candida ; Candida albicans ; Drug Resistance ; Enterococcus ; Escherichia coli ; Fungi ; Gram-Positive Cocci ; Klebsiella pneumoniae ; Korea ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Methods ; Pneumonia ; Pseudomonas aeruginosa ; Staphylococcus aureus ; Staphylococcus epidermidis

BACKGROUND: Tapocin(R) is a recently produced Teicoplanin in Korea. To evaluate its clinical usefulness, we compared clinical outcome and safety of Tapocin(R) with those of Teicoplanin (Targocid(R)) against infection caused by multi-drug resistant gram positive cocci. MATERIALS AND METHODS: Twenty-four adult patients infected with multi-drug resistant gram positive cocci were enrolled and randomized into each treatment arm after informed consents were obtained. All patients were given one of the test articles for 7 to 14 days intravenously. Clinical outcome and safety were compared between the two groups. Statistical analysis was done by Chi-square test, Student's t-test, and Fisher's exact test. RESULTS: Twenty out of 24 enrolled patients could be evaluated for clinical efficacy and safety (10 patients for each treatment arm). The baseline characteristics were not significantly different between the two groups in terms of mean age, sex ratio, underlying diseases, site of infections, and causative microorganisms. MRSA was the most common organism: 66.67% in Tarpocin(R) and 91.67% in Targocid(R) groups. Total doses of Targocid(R) and Tapocin(R) administered were 24 and 23 vials, respectively. Fever resolved in 90% of treated subjects and there were no significant differences between the two groups. Bacteriological response shows that the causative microorganisms were eradicated except for one MRSA isolate from each group. Drug fever, as a side effect, was reported from one subject in each group. CONCLUSION: Efficacy and safety of Tapocin(R) is comparable to those of Targocid(R) for the treatment of infections with multi-drug resistant gram-positive cocci.
Adult ; Arm ; Fever ; Gram-Positive Cocci* ; Humans ; Korea ; Methicillin-Resistant Staphylococcus aureus ; Sex Ratio ; Teicoplanin

BACKGROUND: Tapocin(R) is a recently produced Teicoplanin in Korea. To evaluate its clinical usefulness, we compared clinical outcome and safety of Tapocin(R) with those of Teicoplanin (Targocid(R)) against infection caused by multi-drug resistant gram positive cocci. MATERIALS AND METHODS: Twenty-four adult patients infected with multi-drug resistant gram positive cocci were enrolled and randomized into each treatment arm after informed consents were obtained. All patients were given one of the test articles for 7 to 14 days intravenously. Clinical outcome and safety were compared between the two groups. Statistical analysis was done by Chi-square test, Student's t-test, and Fisher's exact test. RESULTS: Twenty out of 24 enrolled patients could be evaluated for clinical efficacy and safety (10 patients for each treatment arm). The baseline characteristics were not significantly different between the two groups in terms of mean age, sex ratio, underlying diseases, site of infections, and causative microorganisms. MRSA was the most common organism: 66.67% in Tarpocin(R) and 91.67% in Targocid(R) groups. Total doses of Targocid(R) and Tapocin(R) administered were 24 and 23 vials, respectively. Fever resolved in 90% of treated subjects and there were no significant differences between the two groups. Bacteriological response shows that the causative microorganisms were eradicated except for one MRSA isolate from each group. Drug fever, as a side effect, was reported from one subject in each group. CONCLUSION: Efficacy and safety of Tapocin(R) is comparable to those of Targocid(R) for the treatment of infections with multi-drug resistant gram-positive cocci.
Adult ; Arm ; Fever ; Gram-Positive Cocci* ; Humans ; Korea ; Methicillin-Resistant Staphylococcus aureus ; Sex Ratio ; Teicoplanin

Globicatella sanguinis is an unusual pathogen causing bacteremia, meningitis, and urinary tract infection, and can be misidentified as Streptococcus pneumoniae or viridans streptococci due to its colonial morphology. A 76-year-old female patient with hypertension and degenerative arthritis was admitted to the hospital complaining of knee joint pain. Blood culture revealed the presence of Gram-positive cocci, and the isolated organism was equally identified as S. pneumoniae using the MicroScan identification system (Beckman Coulter, USA) and Vitek 2 identification system (bioMérieux, USA). However, the isolate showed optochin resistance based on the optochin disk susceptibility test. The organism was finally confirmed to be G. sanguinis based on 16S rRNA sequencing and hydrogen sulfide production testing. Accurate identification of G. sanguinis isolated from aseptic body fluids including blood is important for appropriate antibiotic selection based on accurate application of interpretative criteria of antimicrobial susceptibility test.
Aged ; Bacteremia* ; Body Fluids ; Female ; Gram-Positive Cocci ; Humans ; Hydrogen Sulfide ; Hypertension ; Knee Joint ; Meningitis ; Osteoarthritis ; Pneumonia ; Streptococcus pneumoniae ; Urinary Tract Infections ; Viridans Streptococci