Guidelines recommend that clinical laboratories perform phenotypic tests (nitrocefin-based test and penicillin 10-U [P10] or 1-U [P1] zone edge tests) to detect penicillinase in Staphylococcus aureus isolates. This study aimed to assess the prevalence of blaZ encoding penicillinase and perform various phenotypic tests in S. aureus isolates from Japan. We prospectively collected 200 methicillin-susceptible S. aureus isolates from June 2015 to January 2016 and performed six phenotypic tests (nitrocefin-based test, P10 zone edge test/P10 diffusion test, penicillin 2-U [P2] zone edge test/P2 diffusion test, and cloverleaf test) on each sample. We confirmed the presence of blaZ (two blaZ-positive isolates) using PCR. Using blaZ PCR as a standard, we observed a low sensitivity (50%) and positive predictive value (PPV, 50%) of the nitrocefin-based test, low PPV (18.2%) of the P10 zone edge test, low sensitivity (50%) of the P10 diffusion test, low PPV (50% and 22.2%) of the P2 zone edge test and P2 diffusion test, respectively, and low sensitivity (50%) of the cloverleaf test. These data suggest a low performance (sensitivity and PPV) of these six phenotypic tests because of the low prevalence (1%) of blaZ in S. aureus isolates from Japan.
Diffusion ; Japan* ; Penicillinase* ; Penicillins ; Polymerase Chain Reaction ; Prevalence* ; Prospective Studies ; Staphylococcus aureus* ; Staphylococcus*

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

From 1992 to 2001, penicillin resistance of betalactamase-producing Neisseria gonorrhoeae was supervised by Institute of Dermato-Venereology. Results: the rate of penicillin-resistant gonococcal strains was highest in1995 (about 76%), and in 1996 (73.11%), especially in 3 years (1999-2001) this rate decreased significantly: 51.3%, 47.10%, and 35.54%, respectively
Neisseria gonorrhoeae ; Neisseria ; penicillinase

penicillinase-resistant agents against penicillinase. These infections are very difficult to treat because they have resistance to almost every antibiotics except for vancomycin. We experienced MRSE(methicilline-resistant staphylococcal epidermis) infected 56 years old man who developed 2 months after arthroplasty for TMJ ankylosis and MRSA(methicilline-resistant staphylococcal aureus) infected 59 years old man who was performed arthroplasty for traumatic TMJ disc displacement.]]>
Ankylosis ; Anti-Bacterial Agents ; Arthroplasty ; Humans ; Methicillin Resistance ; Methicillin ; Methicillin-Resistant Staphylococcus aureus ; Middle Aged ; Penicillinase ; Staphylococcal Infections ; Temporomandibular Joint ; Vancomycin

BACKGROUND: The prevalence of extended-spectrum beta-lactamase(ESBL)-producing organisms has been increasing in Korea. We performed a study to characterize various TEM derivatives with clinical isolates of Klebsiella pneumoniae collected from 3 hospitals in Korea. METHODS: Fifty-seven isolates of ESBL-producing K. pneumoniae collected from 3 hospitals were screened by TEM-specific PCR for the carriage of TEM genes. Thirteen strains were found to have TEM-related genes. Eleven blaTEM genes were amplifed and sequenced. The transfer of resistance was tested by conjugation and isoelectric points of beta-lactamases were determined. MICs were measured to obtain a resistance pattern for each indivudual wild- type and transconjugant strain. The hydrolysis rate of TEM-52 was measured spectrophotometrically. RESULTS: Ten strains carried plasmid-mediated CTEM-52 gene, which sequence showed the substitution of 3 amino acids compared to that of TEM-1: 104 glutamic acid --> lysine (GAG --> AAG), 182 methionine --> threonine (ATG --> ACG), and 238 glycine --> serine (GGT --> AGT). MIC showed that TEM-52 mediated a resistance to ceftazidime and aztreonam at a lower level than to cefotaxime. TEM-52 enzyme hydrolyzed cefotaxime efficiently (Vmax, 340) and showed fairly weak activity for ceftazidime (Vmax, 15.1), but very weak activity for aztreonam. The gene of TEM-52 beta-lactamases was mediated by approximately 77-kb plasmids. CONCLUSION: From these results, we conclude that the TEM-52 beta-lactamase is a common TEM- type ESBL in K. pneumoniae in Korea.
Amino Acids ; Aztreonam ; beta-Lactamases* ; Cefotaxime ; Ceftazidime ; Glutamic Acid ; Glycine ; Hydrolysis ; Isoelectric Point ; Klebsiella pneumoniae* ; Klebsiella* ; Korea ; Lysine ; Methionine ; Penicillinase ; Plasmids ; Pneumonia ; Polymerase Chain Reaction ; Prevalence ; Serine ; Threonine

BACKGROUND: Recent clinical isolates of bacteria often produce various beta-lactamases, for example, extended spectrum beta-lactamase (ESBL) by some species of Enterobacteriaceae, TEM beta-lactamase by Haemophilus influenzae, and penicillinase by methicillin-susceptible Staphylococcus aureus (MSSA). Cefminox, a commonly used cephamycin, is stable to various beta-lactamases, but its activity against recent clinical isolates has not been evaluated. The aim of this study was to determine the activities of cefminox against recent clinical isolates of Enterobacteriaceae, H. influenzae, and MSSA. METHODS: The organisms, isolated from Severance Hospital patients during 1997 to 1998, were kept frozen until the test. Antimicrobial susceptibility was determined by the NCCLS agar dilution method. RESULTS: All 30 isolates of Escherichia coli and 90% of 30 Klebsiella pneumoniae isolates were susceptible to cefminox, cefotetan and amikacin. All of the Enterobacter cloacae and Serratia marcescens, and 86% of Citrobacter freundii isolates were susceptible to amikacin. All of the 15 isolates each of Proteus mirabilis, P. vulgaris and Morganella morganii were susceptible to cefminox, cefotetan, cefotaxime, ceftazidime, and aztreonam, while all of the Providencia spp. were susceptible to ceftazidime and aztreonam. All of the 29 H. influenzae isolates were susceptible to cefminox, cefotaxime, and levofloxacin, while all MSSA isolates were susceptible to cefoxitin and cotrimoxazole. CONCLUSION: Cefminox is more active than the other beta-lactams against Enterobacteriaceae including, ESBL- producing E. coli, and K. pneumoniae.
Agar ; Amikacin ; Aztreonam ; Bacteria ; beta-Lactamases ; beta-Lactams ; Cefotaxime ; Cefotetan ; Cefoxitin ; Ceftazidime ; Citrobacter freundii ; Enterobacter cloacae ; Enterobacteriaceae* ; Escherichia coli ; Haemophilus influenzae* ; Haemophilus* ; Humans ; Influenza, Human ; Klebsiella pneumoniae ; Levofloxacin ; Morganella morganii ; Penicillinase ; Pneumonia ; Proteus mirabilis ; Providencia ; Serratia marcescens ; Staphylococcus aureus* ; Staphylococcus* ; Trimethoprim, Sulfamethoxazole Drug Combination

BACKGROUND: Resistance to beta-lactams in E. coli is mostly via acquisition of plasmid-mediated beta-lactamase gene. Among the plasmid-mediated beta-lactamases, TEM-1 beta-lactamase is by far the most prevalent among ampicillin-resistant E. coli. The prevalence of TEM-1 or TEM-2 ranged from 61% to 98% across the surveys. Klebsiella species generally have class A chromosomal beta-lactamases, which differ greatly from the class C types. Most K. pneumoniae isolates have chromosomally mediated SHV-1 beta-lactamase in most surveys. There has been only one report of prevalence and types of beta-lactamases in E. coli and K. pneumoniae in Korea. We performed this study to determine the prevalence and types of beta-lactamases in E. coli and K. pneumoniae isolated in Korea. METHODS: Ampicillin resistance was determined by disk diffusion test (E. coli) and agar dilution method (K. pneumoniae). Fifty five isolates of E. coli and 92 isolates of K. pneumoniae which were derived from patients in 2 university hospitals in Korea during 1996 were tested by TEM- and SHV-specific PCR. RESULTS: The ampicillin resistance rate in E. coli and K. pneumoniae was 82% and 94.6%, respectively. TEM-type beta-lactamase gene was found in 53% of E. coli isolates. 93.5% of K. pneumoniae isolates was found to have SHV-type beta- lactamase gene. CONCLUSION: In Korea TEM-type beta-lactamase gene was most prevalent in E. coli, but its prevalence rate was relatively low compared with those in other country. For K. pneumoniae, the isolates with SHV type beta-lactamase gene were predominant.
Agar ; Ampicillin Resistance ; beta-Lactamases* ; beta-Lactams ; Diffusion ; Escherichia coli* ; Escherichia* ; Hospitals, University ; Humans ; Klebsiella pneumoniae* ; Klebsiella* ; Korea* ; Penicillinase ; Pneumonia ; Polymerase Chain Reaction ; Prevalence*

Decreased sensitivity of N. gonorrhoeae to many existing antibiotics and the emergence and increase of penicillinase producing and of spectinomycin resistant N. gonorrhoeae necessitate intensive efforts to study on resistance. Male patients with uncomplicated gonococcal urethritis treated during the year 1990 at the VD clinic of Choong-ku Public Health Center in Seoul were included in this study. A total of 85 strains, 44 strains of non-PPNG and 41 strains of PPNG isolated from the patients were studied to evaluate their sensitivities to ampicillin, penicillin, cefoxitin, kanamycin, tetracycline, erythromycin, spectinomycin and cotrimazole. The results are summerized as follw: In non-PPNG strains, the range of MICs. MIC50 and MIC90 for both ampicillin and penicillin were 0.125-32, 2 and 16 mcg/ml respectively. For cefoxitin, they were 0.125-8, s and 16 mcg/ml respectively, and for kanamycin, 8--<64, 32 and 64 mcg/ml, respectively. For tetracycline, they were 1-64, 8 and 32 mcg/ml, while for erythromycin, 0.06-16, 2 and 8 mcg/ml respectively. For spectinomycin, they were 4--<64, 32 and 64 mcg/ml and for cotrimazole, 5--<160, 40 and 160 mcg/ml respectively. In the case of PPNG, the range of MICS, MIC50 and MIC90 for ampicillin were 8--<128, 32 and 128 mcg/ml respectively but for penicillin, 8--<128, 64 and 128 mcg/ml respectively. And for cefoxitin, they were 0.5-32, 4 and 16 mcg/ml while for kanamycin, 16--<64, 64 and >64 mcg/ml respectively. For tetracycline, the values were 2-64, 16 and 32 mcg/ml, and for erythromycin, they were 0.5-16, 4 and 8 mcg/ml respectively. for spectinomycin, they were 8--<64, 32, and 64 mcg/ml and finally for cotrimazole, 5--<160, 80 and 160 mcg/ml respectively. From these results, it is concluded that the MICs of both PPNG and non-PPNG were about 2 folds higher than the results of sensitivity tests at the same instituition in 1985. 2) The prevalence of PPNG among 35 gonorrhoeae patients who received treatment before the visit was 60% (21/35), while that among the patients without previous treatment was 40% (20/50). 3) In the cases of ampicillin, penicillin and cotrimazole, their MIC values were found to be significantly higher for the strains isolated from the patients with previous treatment history than those without previous treatment (p<0.05). 4) In non-PPNG strains, a significant positive correlation is found between the sensitivities to most pairs of ampicillin, penicillin, cefoxitin, kanamycin, tetracycline, erythromycin and spectinomycin. However this excludes some pairs such as : tetracycline-cefoxitin, erythromycin-penicillin, erythromycin-cefoxitin, spectinomycin-penicillin, and spectinomycincefoxitin (p<0.05). 5) In PPNG strains, a significant positive correlation is also found between the sensitivities to most pairs of ampicillin, penicillin, cefoxitin, tetracycline, erythromycin and spectinomycin. However, the exceptional cases include tetracycline-cefoxitin, erythromyoinpenicillin, erythromycin-cefoxitin, spectinomycin-penicillin, and spectinomycin-cefoxitin pairs. In addition, the sensitivity to kanamycin was found to be strongly correlated with that to tetracycline, erytheromycin and spectinomycin (p<0.05). Therefore it is essential for the management fo gonorrhoeae, together with a correct diagnosis, to use currently most effective treatment regimens which would also prevent the emergence of resistant strains. It is also suggested that when a treatment is failed, to use the durg which do not show correlation in sensitivities on re-treatment.
Ampicillin ; Anti-Bacterial Agents ; Antibodies* ; Cefoxitin ; Diagnosis ; Erythromycin ; Humans ; Kanamycin ; Male ; Penicillinase ; Penicillins ; Prevalence ; Public Health ; Seoul ; Spectinomycin ; Tetracycline ; Urethritis

Because of increasing resistance of circulating N. gonorrhoeae and frequent failures in the treatment of gonorrhoea, intensive work on gonorrhoea has become of paramount importance. During January 1980-April 1984, at the Choong-Ku VD Clinic in Seoul, 3,340 male patients with uncomplicated gonococcal urethritis were treated with various treatment regimens. Diagnosis of gonorrhoea and declaration of a treatment failure were made on the basis of positive urethral culture. In 1984, the prevalence of Penicillinase Producing N. gonorrhoeae (PPNG) was about 30%, The pretreatment minimun inhibitory concentration of various antibiotics were quite high. Even for non-PPNG urethritis standard penicillin regimens gave unsatisfactory results. For PPNG urethritis, only spectinomycin, cefoperazone and cefotaxim-probenecid regimens gave satisfactory results. No spectmomycin resistant strain of N. gonorrhoeae has been found since 1982 at the Choong-Ku VD Clinic. As an agent of single drug therapy, spectinomycin seems to be one of the most cost effective drugs in the treatment of uncomplicated gonorrhoea in men.
Anti-Bacterial Agents ; Cefoperazone ; Diagnosis ; Drug Therapy ; Humans ; Male ; Penicillinase ; Penicillins ; Prevalence ; Seoul ; Spectinomycin ; Treatment Failure ; Urethritis

Between December 18, 1985 and May 31, 1986 at the VD Clinic, Choong-ku Public Health Center, in Seoul, 274 male patients with uncomplicated gonococcal infection, including 124 penicillinase producing Neisseria gonorrhoeae(PPNG) infection, were entered into the study. They were divided randomly into the group A and the group B. In the group A, treated with kanamycin 2g, im regimen, 126 of 137 patients were followed and 86 patients(68.3%) were cured. In the group B, treated with gentamicin 240mg, im regimen, 125 of 137 patients were followed and 78 patients(62.4%) were cured. The cure rates in PPNG urethritis were 63.9%(39/61) in the group A and 50.9%(29/57) in the group B. The cure rates in non PPNG urethritis were 72.3%(47/65) in the group A and 72.1% (49/68) in the group B. No significant difference was observed in cure rates between two groups. It is suggested that. both kanamycin 2g, im regimen and gentamicin 240mg, im regimen is not suitable for a first line treatment for uncomplicated gonococcal urethritis.
Gentamicins* ; Humans ; Kanamycin* ; Male* ; Neisseria ; Penicillinase ; Public Health ; Seoul ; Urethritis*