Detection of pathogenic Vibrio species and antibiogram activity in Asian Seabass (Lates calcarifer) in Tumpat, Kelantan

@#Some of Vibrio species is well known as pathogenic bacteria in aquaculture and the marine industry. Its infection is able to generate a massive outbreak and affect the fish population, especially for net caged fish such as seabass. This study was conducted to investigate the prevalence of Vibrio spp. isolated from seabass (Lates calcarifer) in Sri Tujuh Lagoon, Tumpat, Kelantan. Then, to determine the antibiotic resistance in Vibrio isolates. Polymerase chain reaction (PCR) was used to detect Vibrio species using specific primer VR169 and VR744 with estimation base pair size band, 597 bp and further identified by sequencing. On the other hand, antibiotic susceptibility tests were continued by using 13 types of antibiotics; kanamycin (K30), chloramphenicol (C30), neomycin (N10), ampicillin (AMP10), nitrofurantoin (F300), tetracycline (TE30), streptomycin (S10), norfloxacin (NOR10), ciprofloxacin (CIP5), nalidixic acid (NA30), gentamicin (CN10), doxycycline (DO30) and sulfamethoxazole (SXT100). As a result, 14 Vibrio isolates were identified, including Vibrio fluvialis (n=6), Vibrio parahaemolyticus (n=3), Vibrio harveyi (n=2) and each isolate for Vibrio vulnificus, Vibrio alginolyticus and Vibrio spp. The results showed that all isolates were sensitive to most antibiotics except ampicillin, neomycin and streptomycin. The MAR index value was ranging from 0 to 0.31. This study demonstrates the prevalence of Vibrio spp. in seabass and the report on multidrug resistance strains that could be of concern to the fish farmers. In addition, data from this study can be further used in fish disease management plans.

A Prospective Study on Prevalence of Micro- Organisms Isolated from Ear Swab in a tertiary Care Teaching Hospital in Mathura

Background: Ear infection is an inflammation of the ear. Ear discharge is one of the most common symptoms of ear infection. Approximately, 65-330 million people suffer from ear infection worldwide. Around 60% of them had significant hearing impairment Methods: The duration of study was over a period of one year.400 cases were included with ear infection. This study was conducted in the Department of ENT, K M Medical College & Hospital, Mathura. Result: This study suggested that 40% bacteria were P. aeruginosa followed by Proteus mirabilis, Klebsiella pneumoniae, E. coli & Citrobacter spp.in gram negative bacteria. Conclusion: This study suggested that Ciprofloxacin and gentamycin were the most sensitive against pseudomonas aeruginosa and Staphylococcus aureus. Use of antibiotics for treating Pseudomonas aeruginosa and Staphylococcus aureus infections in otitis media, alert us against indiscriminate usage of antibiotics to prevent development of resistance.

Biofilm production and its correlation with antibiotic resistance pattern among clinical isolates of Pseudomonas aeruginosa in a tertiary care hospital in north-east India

Background: Pseudomonas aeruginosa is an ubiquitous pathogen capable of surviving in a variety of environmental conditions. It is increasingly gaining importance as a multidrug resistant nosocomial pathogen. Biofilm acts as a barrier, reducing the penetration of these drugs and consequently, preventing them from exercising their actions. The aim of this study is to isolate and identify Pseudomonas aeruginosa from various clinical specimen and to find out their production of biofilms and their correlation with antibiotic susceptibility pattern.Methods: All Pseudomonas aeruginosa over a period of 1 year were isolated and identified from clinical specimens and antibiotic susceptibility test was done following standard operative procedures. Biofilm detection was done by Congo Red Agar method (CRA).Results: 134 isolates of Pseudomonas aeruginosa was isolated. Maximum isolates were isolated from sputum samples 55 (41%) and most were from wards 68 (51%) giving a probability of increased healthcare associated infections. Biofilm production by the isolates was seen in 39 (29%). All the biofilm producing isolates shows more resistant pattern in comparison to non-biofilm producers. 69% of Imipenem and 82% of Meropenem resistant isolates produce biofilm. All the P. aeruginosa including MDR and biofilm forming strains were sensitive to Colistin.Conclusions: Resistance to antimicrobial agents is the most important feature of biofilm infections. Ability of P. aeruginosa to form biofilms renders antibiotic treatments inefficient and therefore promotes chronic infectious diseases. As a result, infections caused by bacterial biofilms are persistent and very difficult to eradicate.

Tasa de incidencia de mastitis clínica y susceptibilidad antibiótica de patógenos productores de mastitis en ganado lechero del norte de Antioquia, Colombia* / Incidence rate of clinical mastitis and antibiotic susceptibility of mastitis-producing pathogens in dairy cattle from Northern Antioquia, Colombia / Taxa de incidência de mastite clínica e susceptibilidade antibiótica de patógenos produtores de mastite em gado leiteiro do norte de Antioquia, Colômbia

Resumen Introducción: la mastitis se define como la inflamación de la glándula mamaria causante de grandes pérdidas económicas en hatos lecheros, lo que amerita su investigación. Objetivo: determinar la tasa de incidencia de mastitis clínica TIMC, la etiología asociada y la sensibilidad antibiótica de patógenos aislados de casos de mastitis en ganado lechero. Materiales y métodos: se siguieron 37 hatos por 12 meses para el diagnóstico de mastitis cílínica (MC). A las muestras de leche de los casos de MC se les realizó cultivo bacteriológico y a estas, así como a los aislamientos de casos de mastitis subclínica de un estudio previo, se les efectuó prueba de susceptibilidad antibiótica. Para el análisis de la información se utilizó estadística descriptiva estándar. Resultados: TIMC fue de 13,8 casos por 100 vacas-año a riesgo. Se aislaron 188 patógenos totales de casos de MC, entre los cuales el Streptococcus agalactiae, el Streptococcus pyogenes y el Corynebacterium spp. fueron los más frecuentes, con 29,8; 11,7 y 5,9 %, respectivamente. Se halló una alta sensibilidad de las bacterias contagiosas para los antibióticos cloxacilina y cefoperazone. Conclusiones: en el presente estudio se encontró una TIMC de 13,8 casos por 100 vacas-año a riesgo. Los patógenos más prevalentes identificados en casos de MC fueron contagiosos. Se encontró una alta sensibilidad de las bacterias contagiosas para la mayoría de los antibióticos β-lactámicos.

Abstract Introduction: Mastitis is defined as the inflammation of the mammary gland causing great economic losses in dairy herds, which merits investigation. Objective: To determine the incidence rate of clinical mastitis IRCM, associated etiology, and antibiotic sensitivity of pathogens isolated from cases of mastitis in dairy cattle. Materials and methods: 37 herds were followed during 12 months for clinical mastitis (CM) diagnosis. Milk samples from CM cases were bacteriologically cultured, which underwent, along with isolates from subclinical mastitis cases from a previous study, antibiotic susceptibility testing. For data analysis, standard descriptive statistics were used. Results: The IRCM was 13.8 cases per 100 cows-year at risk. A total of 188 pathogens of CM cases were isolated, among which Streptococcus agalactiae, Streptococcus pyogenes, and Corynebacterium spp. were the most frequent, with 29.8%, 11.7%, and 5.9%, respectively. A high susceptibility of contagious bacteria was found for cloxacillin and cefoperazone. Conclusions: The present study found an IRCM of 13.8 cases per 100 cows-year at risk. The most prevalent pathogens identified in cases of CM were contagious. A high sensitivity of contagious bacteria was found for most β-lactam antibiotics.

Resumo Introdução: a mastite se define como a inflamação da glândula mamária causante de grandes perdas econômicas em rebanhos de gado leiteiro, o que justifica a sua pesquisa. Objetivo: determinar a taxa de incidências de mastite clínica TIMC, a etiologia associada e a sensibilidade antibiótica de patógenos isolados de casos de mastite em gado leiteiro. Materiais e métodos: seguiram-se 37 rebanhos bovinos durante 12 meses para o diagnóstico de mastitis clínica (MC). Com as amostras de leite dos casos de MC realizou-se cultivo bacteriológico e a estas, assim como aos isolamentos de casos de mastite subclínica de um estudo prévio, efetuou-se prova de susceptibilidade antibiótica. Para a análise da informação se utilizou estatística descritiva padrão. Resultados: a TIMC foi de 13,8 casos por 100 vacas-ano a risco. Foram isolados 188 patógenos totais de casos de MC, entre os quais o Streptococcus agalactiae, o Streptococcus pyogenes e o Corynebacterium spp. foram os mais frequentes, com 29,8; 11,7 e 5,9 %, respectivamente. Constatou-se uma alta sensibilidade das bactérias contagiosas para os antibióticos cloxacilina e cefoperazone. Conclusões: neste estudo evidenciou-se uma TIMC de 13,8 casos por 100 vacas-ano a risco. Os patógenos mais prevalentes identificados em casos de MC foram contagiosos. Encontrou-se uma alta sensibilidade das bactérias contagiosas para a maioria dos antibióticos β-lactâmicos.

Analysis on the infecion status and drug resistant rate of mycoplasma in infertility patients in Puyang city / 国际检验医学杂志

Objective To observe the infecion status and drug resistant rate of mycoplasma in infertility patients in Puyang city and to guide useing drug rationally.Methods A total of 500 women in reproductive period in Puyang city were recruited in this study,collected their vaginal discharge specimen,then cultured and detected ureaplasma urealyticum(Uu) and mycoplasma hominis(Mh) by liquid culture method and solid culture method.The women with positive results were divided as the pregnancy group and infertility group.The sensitivity rate of mycoplasma to 12 kinds of antibiotic were tested.Results The positive rate of mycoplasma in all the 500 women was 44.0%(220/500),the constituent ratio of pregnancy group(60 cases) was 27.3%,and the constituent ratio of infertility group (160 cases) was 72.7%.The difference was statistically significant between infertility group and pregnancy group(P<0.05).The Uu infection rates in pregnancy group and infertility group were 71.6% and 76.2% respectively,and the Mh infection rates were 11.6%,11.2% respectively.The rates of infecting Uu and Mh at the same time were 16.6% and 12.5%.The mycoplasma in and infertility group the pregnancy group were sensitive to spectinomycin,doxycycline and capminocim,which were 91.8%,92.1%,88.3%;90.9%,90.9%,87.3%.Conclusion The infection rate of Uu is higher than Mh in patients with infertility,which is resistant to quinolone classes and large ring lactone class antibiotic.

Identification of a pathogenic Aeromonas veronii isolated from rock carp, Procypris rabaudi / 中国人兽共患病学报

In June 2016,a disease among the cultured rock carp (Procypris rabaudi) in Yongchuan of Chongqing Municipality occurred.The aim of this study was to investigate biological characteristics and provide reference for Aeromonas veronii identification diagnosis and treatment.Pathogenic bacteria strain YY01 from the dying fishes were examined and isolated.Strain YY01's taxonomic status was identified by observing the morphology,studying the physiological and biochemical characters and sequencing the 16S rRNA and housekeeping gene gyrB.Its pathogenicity was checked by artificial infection experiment and virulence genes.Furthermore,effective medicine was detected by drug sensitivity.The 16S rRNA and gyrB gene sequence of the strain YY01 was more than 99％ homology with that of Aeromonas veronii,suggesting that the pathogen was Aeromonas veronii,which was also identified by the results of biochemical analysis.The LD50 of strain YY01 to rcok carp was 5.06 × 104 CFU/g.Four virulence genes were detected from YY01,including aerolysin (aer),hemolysin (Hly),Outer Membrane Protein Gene A (OmpA) and adhesion (Aha) genes.Antibiotic sensitivity assays showed that among 40 antibiotics tested,22 were sensitive and 11 were resistant.In conclusion,the strain YY01 is identified as Aeromonas veronii and it is proved to have strong pathogenicity.

Characteristics of drug resistance and molecular type of Salmonella typhi and Salmonella paratyphi isolated in Henan province, 2009-2011 / 中华流行病学杂志

Objective To investigate the antibiotic resistance and pulsed field gel electrophoresis (PFGE) patterns of clinical isolates of Salmonella (S.) typhi and S.paratyphi in Henan province during 2009-2011.Methods According to molecular typing and Salmonella K-B drug susceptibility test method published by international PulseNet bacterial infectious disease monitoring network and USA Clinical and Laboratory Standards Institute (CLSI),the drug susceptibility and PFGE molecule characteristics of 78 S.typhi and S.paratyphi strains isolated from sentinel hospitals in Henan were analyzed.Results The 78 strains orS.typhi and S.paratyphi were resistant to 13 kinds of antibiotics,in which 62 were multidrug resistant (79.5％),4 were resistant to 2-3 kinds of antibiotics (5.1％),41 were resistant to 5-8 kinds of antibiotics (52.6％),14 were resistant to 9-10 kinds of antibiotics (17.9％),3 were resistant to 11-12 kinds of antibiotics (3.8％).The resistant rate to cephalosporins,quinolones and other 3 kinds of antibiotic showed an increase trends.Seventy two strains ofS.typhi and S.paratyphi could be divided 14 molecular patterns by digestion with Xba Ⅰ and PFGE,each pattem contains 1-47 strains which shared the similarity of 66.03％-100.00％.Conclusions The drug resistance of clinical isolates of S.typhi and S.paratyphi was serious in Henan.The PFGE patterns showed diversity,but the predominant patterns could be still found.The PFGE patterns of some strains were associated with their drug resistance.

Etiology and drug resistance of non-typhi Salmonella in Henan province, 2011-2015 / 中华流行病学杂志

Objective To analyze the serotypes and antibiotic resistance phenotypes of non-typhi Salmonella strains in Henan province from 2011 to 2015.Methods The stool samples were collected from diarrhea patients,and enriched with SBG enrichment broth and the pathogen isolation was conducted with CHROMAgar selective culture medium at 37 ℃ for 18-24 hours using KIA/MIU biochemical action and API20E biochemical system slab to identify Salmonella strains.The serotypes of all the positive strains were detected with SSI Salmonella typing sera.According to K-B drug susceptibility testing method published by USA clinical and Laboratory Standards Institute (CLSI),the antibiotics resistant phenotype of the positive strains were analyzed.Results A total of 1 351 strains of non-typhi Salmonella were isolated,in which 811 were from males,540 were from females.The ratio of men to women was 1.5 ∶ 1.Children and young adults were mainly affected.The pathogen isolation was mainly in May-October during a year.The 1 351 strains of non-typhi Salmonlla were divided into 58 serotypes.S.enteritidis,S.typhimurium,S.agona,S.derby,S.indiana,S.senfienberg and S.thompson ranked 1st-7th.The drug-resistance rate of the 1 351 strains was 46.1％ to synthetic broad-spectrum penicillin ampicillin (AMP),19.5％ and 21.2％ to the three generation cephalosporin ceftazidime (CAZ) and cefotaxime (CTX),8.8％ to the four generation cephalosporins cefepime (FEP),58.7％ to the one generation of quinolones nalidixic acid (NAL),14.7％ to the three generation fluoroquinolone ciprofloxacin (CIP) and norfloxacin (NOR),25.0％ and 35.6％ to aminoglycoside antibiotic gentamicin (GEN) and streptomycin (STR),35.4％ to amphenicols (CHL),31.7％ to sulfonamide trimethoprim (TMP) and 37.8％ to tetracycline (TET).Totally 879 strains were multidrug resistant (65.1％):350 strains were resistant to 3-4 kinds of antibiotics (25.9％),309 strains were resistant to 5-7 kinds of antibiotics (22.9％),174 strains were resistant to 8-10 kinds of antibiotics (12.9％) and 48 strains were resistant to 11-12 kinds of antibiotics (3.6％).Conclusion The serotypes of non-typhi Salmonella strains isolated from Henan province varied,some strains were resistant to 12 kinds of antibiotics commonly used in clinical treatment and the multidrug resistance has become serious.

Etiology and drug resistance of non-typhi Salmonella in Henan province, 2011-2015 / 中华流行病学杂志

Objective To analyze the serotypes and antibiotic resistance phenotypes of non-typhi Salmonella strains in Henan province from 2011 to 2015.Methods The stool samples were collected from diarrhea patients,and enriched with SBG enrichment broth and the pathogen isolation was conducted with CHROMAgar selective culture medium at 37 ℃ for 18-24 hours using KIA/MIU biochemical action and API20E biochemical system slab to identify Salmonella strains.The serotypes of all the positive strains were detected with SSI Salmonella typing sera.According to K-B drug susceptibility testing method published by USA clinical and Laboratory Standards Institute (CLSI),the antibiotics resistant phenotype of the positive strains were analyzed.Results A total of 1 351 strains of non-typhi Salmonella were isolated,in which 811 were from males,540 were from females.The ratio of men to women was 1.5 ∶ 1.Children and young adults were mainly affected.The pathogen isolation was mainly in May-October during a year.The 1 351 strains of non-typhi Salmonlla were divided into 58 serotypes.S.enteritidis,S.typhimurium,S.agona,S.derby,S.indiana,S.senfienberg and S.thompson ranked 1st-7th.The drug-resistance rate of the 1 351 strains was 46.1％ to synthetic broad-spectrum penicillin ampicillin (AMP),19.5％ and 21.2％ to the three generation cephalosporin ceftazidime (CAZ) and cefotaxime (CTX),8.8％ to the four generation cephalosporins cefepime (FEP),58.7％ to the one generation of quinolones nalidixic acid (NAL),14.7％ to the three generation fluoroquinolone ciprofloxacin (CIP) and norfloxacin (NOR),25.0％ and 35.6％ to aminoglycoside antibiotic gentamicin (GEN) and streptomycin (STR),35.4％ to amphenicols (CHL),31.7％ to sulfonamide trimethoprim (TMP) and 37.8％ to tetracycline (TET).Totally 879 strains were multidrug resistant (65.1％):350 strains were resistant to 3-4 kinds of antibiotics (25.9％),309 strains were resistant to 5-7 kinds of antibiotics (22.9％),174 strains were resistant to 8-10 kinds of antibiotics (12.9％) and 48 strains were resistant to 11-12 kinds of antibiotics (3.6％).Conclusion The serotypes of non-typhi Salmonella strains isolated from Henan province varied,some strains were resistant to 12 kinds of antibiotics commonly used in clinical treatment and the multidrug resistance has become serious.

Drug Resistance Spectrum Analysis of 2 527 Clinical Isolates of Bacteria / 现代检验医学杂志

Objective To investigate the resistance of clinical isolates from Yuebei People’s Hospital so as to provide the ref-erence for clinical use of antibiotics.Methods To comprehensively analyze the drug resistance,AST was performed with K-B or MIC method to 2 527 strains of clinical isolates and the data were analyzed by WHONET 5.4 and SPSS19.0 softwares according to the breakpoints of CLSI 2012 standard.Results MRSA accounted for 30.9% in Staphylococcus aureus iso-lates,MRCNS accounted for 76.2% incoagulase negative Staphylococcus isolates ,no detection of vancomycin or linezolid re-sistant strains.The antimicrobial drug resistance of Enterococcus faecium was significantly higher than that of Enterococcus faecalis ,no detection of glycopeptide and linezolid resistant strains in Enterococcus faecalis ,but one linezolid resistant strains and two teicoplanin resistant strains in Enterococcus faecalis .Enterobacteriaceae remain highly sensitive to carbapen-em antibiotics,ESBLs produced strains in Escherichia coli ,Klebsiella pneumoniae were 43.9% and 37.5% respectively,five polymyxin B resistant strains were detected in Pseudomonas aeruginosa ,and 63.7% of MDRO rate in Acinetobacter bau-mannii .Conclusion Drug resistance of clinical pathogenic bacteria remain seriously in hospital,clinical application of antibi-otics should be reasonable based on the result of drug sensitivity.

In Vitro Bacteriostatic Effects of Rifampin on Orientia tsutsugamushi

We performed an in vitro cell culture experiment to ascertain whether rifampin exhibits bactericidal effects against Orientia tsutsugamushi, the causative agent of scrub typhus. ECV304 cells were infected with the Boryong or AFSC-4 strain of O. tsutsugamushi and then, the cultures were maintained in media with increasing concentrations of rifampin, azithromycin, doxycycline, or chloramphenicol for 4 days. On day 5, the media were replaced with fresh antibiotic-free medium and the cultures were maintained until day 28. On days 5, 13, and 28, immunofluorescence (IF) staining of O. tsutsugamushi was performed. IF staining on days 13 and 28 revealed increasing numbers of IF-positive foci in all cultures, even in cultures initially exposed to the highest concentration of rifampin (80 microg/mL), azithromycin (80 microg/mL), doxycycline (20 microg/mL), or chloramphenicol (100 microg/mL). The present study reveals that rifampin has no bactericidal effect against O. tsutsugamushi as observed for azithromycin, doxycycline, and chloramphenicol. A subpopulation of the bacteria that are not killed by high concentrations of the antibiotics may explain the persistence of O. tsutsugamushi in humans even after complete recovery from scrub typhus with antibiotic therapy.

Analysis of mycoplasma infection and drug susceptibility in 6 573 patients with nongonococcal urethritis / 国际检验医学杂志

Objective To investigate the infection status and drug suscepetibility of mycoplasma from 6 573 patients with non-gonococcal urethritis ,and to provide the scientific bases for the clinical application of antibiotics .Methods Mycoplasma detection kit was used to detect ureaplasma urealyticum (Uu) and mycoplasma hominis(Mh) and the drug susceptibility .All the patients were divided into two groups :Chinese group and foreigner group .Results Among 5 675 Chinese patients ,2 985 patients were infected by mycoplasma(52 .6% ) .The infection rate of Uu was 2 312(40 .7% ) .35 .2% patients were male ,and 61 .4% patients were female .In 898 foreign patients ,440 patients were infected by mycoplasma(49 .0% ) .The infection rate of Uu was 327(36 .4% ) .32 .2% pa-tients were male ,and 59 .5% patients were female .In Chinese patients infected by Uu ,the susceptibility rates to MIN ,DOX ,JOS and CLA were 96 .7% ,96 .2% ,93 .7% ,89 .7% ,respectively .In foreign patients ,the susceptibility rates to MIN ,DOX ,JOS ,and CLA were 98 .9% ,98 .4% ,95 .8% ,92 .1% .Conclusion The mycoplasma infection rate of Chinese patients is higher than foreign patients .In both groups ,Uu infection is the main type .Female patients are more than male patients .The drug sensitivity rate in for-eign group is higher than that in Chinese group .mycoplasma are sensitivity to MIN ,DOX ,JOS .

The Study of Aerobic Bacterial Culture and Antibiotic Susceptibility in Epidermal Cysts / 대한피부과학회지

BACKGROUND: Epidermal cyst is a common acquired skin cyst. When such cysts may be inflamed, they are often referred to as being infected. To clarify the etiology of inflamed epidermal cysts, several studies have carried bacteriology of inflamed and uninflamed epidermal cyst and sought to identify the role of micro-organisms. OBJECTIVE: The aim of this study is to evaluate the bacterial influences on inflammatory process of epidermal cysts and the antibiotic sensitivity of cultured aerobic bacteria in epidermal cysts. METHODS: We carried out the bacterial cultures using sterile swabbing internal materials in each cyst which has been incised after surgical removals of epidermal cyst. An inflamed epidermal cyst was defined as a known cyst that developed a fluctuant soft-tissue swelling surrounded by the erythema and contained a localized collection of purulent material. For the aerobic culture, samples were cultured on blood agar plates, McConkey agar plate and chocolate agar plates in 5% CO2 at 35degrees C for 5 days. Colonies formed were identified based on VITEK2 system. Then antimicrobial susceptibility test were also done on VITEK2 system. RESULTS: Total of 100 epidermal cyst specimens from 96 patients (67 men and 29 women) were involved had confirmed histopathological findings by dermatologists. Seventy were from face and neck, 24 from trunk, 4 from the extremities, 2 from buttock. Of the 53 inflamed cysts, 30 (56.6%) yielded bacterial growth. On the other hand, from the 47 uninflamed cysts, 15 (31.9%) cyst resulted in bacterial growth (p=0.013). The predominant bacteria from inflamed and uninflamed cyst were coagulase-negative Staphylococci (32 isolate of 45 specimens, 71.1%). All cultured bacteria were susceptible to almost all of antibiotics except amoxicillin/clavulanic acid, ampicillin, benzylpenicillin, cefoxitin, cephalothin, fucidic acid, piperacillin, piperacillin/Tazobactam. CONCLUSION: Our study showed that CoNS was predominant in inflamed cysts, which strongly suggests that aerobic bacteria play a role in the inflammatory process and treatment with antibiotics is necessary for epidermal cyst.

Interpretation of Susceptibility Tests in Consideration of Tissue Concentrations of Antimicrobials / 대한임상미생물학회지

BACKGROUND: For an optimum treatment of infections, appropriate antimicrobials should be selected according to the results of antibiotic susceptibility test (AST). However, the present AST does not take into account of antimicrobial concentrations in tissues, although different tissues have different distribution of antimicrobials. Thereby we intended to evaluate the usefulness of interpreting antimicrobial susceptibility depending on tissue concentrations of antimicrobials. METHODS: Gram-negative bacilli isolated from clinical specimens at Yeungnam University Hospital during the period from January to July, 2006 were evaluated retrospectively. The data on blood concentration, half life and tissue distribution of antimicrobials with variable administration route and dosage were collected and arranged in the forms of previous reports. The diameters of the zone of inhibition from the disc diffusion method were converted to minimum inhibitory concentration (MIC) and the organism was regarded as resistant if the converted concentration was higher than the expected concentration in the tissue. RESULTS: Among the data reported as susceptible, antimicrobial concentrations in peritoneal fluid and bile showed a relatively good relationship with AST. But, aminoglycosides and carbenicllin concentrations in wounds and respiratory tissues were shown to be inadequate, thus resulting in a low bacteriologic cure. In cerebrospinal fluid, ciprofloxacin was less effective regardless of dosage. CONCLUSION: Antimicrobial concentration is variable in different tissues and more information on antimicrobial tissue distribution is needed for the appropriate treatment of infections. Reporting of MIC rather than AST with breakpoints should be considered for selection of antimicrobials. Therefore, an interpretation of AST in consideration of the tissue concentration would be more helpful for prevention of major errors and control of infections.

Isolated Rate and Drug Resistance of Mycoplasma from Genitourinary Tract / 中华医院感染学杂志

OBJECTIVE To investigate the characteristics of mycoplasma infection and antifungal resistance to guide the clinical reasonable usage.METHODS Mycoplasma was isolated and its antibiotic susceptibility was detected by Mycoplasma IES test kit.RESULTS Among the 1103 samples,418(37.8%) were positive,including 268 with Ureaplasma urealyticum(Uu)(64.1%),13 with Mycoplasma hominis(Mh)(3.1%),and 137 with mixed infection(Uu and Mh)(32.8%),Young people with the age from 20 to 45 were the highest group of infection(80.1%),Sensitive antibiotics to mycoplasma in precedence order were doxycyline,minocycline,tetracycline,josamycin,and clarythromycin.CONCLUSIONS Mycoplasma is a common pathogen resulting in urogenital tract infection.We should pay more attention to monitor mycoplasma infection and use antibiotics properly and to guide clinically antibiotics usage.

Drug-resistance to Antibiotics of Gramnegative Bacteria in Jinhua Region / 中华医院感染学杂志

OBJECTIVE To study the change in drug-resistance to antibiotics in Gram-negative bacteria in Jinhua region in order to guide clinical application of antibiotics reasonably.METHODS The antibiotics resistance of Gram-negative bacteria from clinical samples in four general hospitals in Jinhua region during from Jan 2005 to Dec 2007 was studied retrospectively.RESULTS The detecting rates of extended-spectrum ?-lactamases in Escherichia coli and Klebsiella pneumoniae were rising from 41.0%and 25.3% in 2005 to 56.0%and 53.2% in 2007,respectively.Furthermore,0.8% isolates were resistant to carbapenemase from all E.coli and K.pneumoniae strains.The rate of antimicrobial resistance to carbapenemase was 20.0% in Pseudomonas aeruginosa and was increased from 27.0% in 2005 to 41.0% in 2007 in Acinetobacter baumannii.CONCLUSIONS The drug-resistance rate in Gram-negative bacteria hase increased obviously in past three years in Jinhua region.It suggests that there be an urgent need for surveillance of Gram-negative bacterial resistance in different hospitals and rational antibiotics usage be emphasized during clinical therapy.

Molecular Mechanisms of Macrolide Resistance of Mycoplasma pneumoniae / 中华医院感染学杂志

OBJECTIVE To investigate macrolide resistance and main molecular mechanisms in Mycoplasma pneumoniae. METHODS Thirty two throat swabs from children infected with M. pneumoniae were cultured by modified Hayflick medium. Antibiotic susceptibility test was used to screen the macrolide-resistant M. pneumoniae. The 23S rRNA gene sequences of the strains were determined with polymerase chain reaction and sequencing. RESULTS Nineteen strains were isolated from 32 throat swabs successfully.Fifteen strains were resistant to macrolide antibiotics according to the results of antibiotic susceptibility test. Once the strain was resistant to one of macrolide antibiotics,it would be resistant to the others. Sequencing results of the sensitive strains and the standard strain FH were completely same. Fifteen resistant strains presented A2063G point mutation in 23 SrRNA region Ⅴ, in which 2 examples showed the coexistence of the sensitive strain and the resistant strain. CONCLUSIONS Macrolide-resistant M. pneumoniae is common and serious at present. The antibiotic resistant isolate carries point mutations of the 23S rRNA region Ⅴ.

Evaluation of Methods for Detection of Antimicrobial Resistance of Acinetobacter baumannii to Imipenem / 대한진단검사의학회지

BACKGROUND: In our hospital, an abrupt increase in the resistant rate of A. baumannii to imipenem was observed. We evaluated the imipenem minimal inhibitory concentration (MIC) of an automated system that our laboratory is using, by comparing with those of other methods. METHODS: During the period from February 2002 to February 2003, the imipenem MICs of the agar dilution method, Etest(R), and the disk diffusion method, were compared for imipenem-resistant A. baumannii tested by an automated system in 46 samples at Chung-Ang University Phil-Dong Hospital. We tested for susceptibility to imipenem with the Vitek system by using the GNI card, the disk diffusion method by using the imipenem disk (BBL(TM)), and the agar dilution method. PCR testing of the isolates for carbapenemase genes (IMP-1 and VIM-2) detected in other hospitals was done using published primers and conditions. RESULTS: By the agar dilution method, 23 (50.0%) isolates were susceptible to imipenem, 14 (30.4%) isolates were intermediate, and 9 (19.6%) isolates were resistant. However, by the Etest, 8 (17.4%) were susceptible to imipenem, and 28 (60.9%) isolates were resistant. By the disk diffusion method, the susceptible isolates were 14 (30.4%) and the resistant isolates were 17 (37.0%). Quantitative agreement between the agar dilution method and the disk diffusion test gave an inverse linear correlation coefficient (r=-0.564). The results of the 13 isolates, whose results of the MIC were below 2 or above 16 in the agar dilution method, corresponded with the Etest and the disk diffusion test. The IMP-1 gene was detected in one isolate. CONCLUSIONS: It is recommended that when a gram-negative bacilli isolate including A. baumannii is characterized as resistant to imipenem by the Vitek system, an additional simple test, such as the disk diffusion assay, might be used.

Evaluation of VITEK-2 System for Antibiotic Susceptibility Test of Streptococcus pneumoniae / 대한임상병리학회지

BACKGROUND: The rapid emergence of multi-drug resistant pneumococcal strains has heightened the importance of reliable and convenient susceptibility testing methods. The newly-developed VITEK-2 (bioMerieux, Inc., Hazelwood, MO, USA) System includes the capability of performing rapid susceptibility testing of Streptococcus pneumoniae using specially configured cards. The objective of this study is to evaluate the performance of the VITEK-2 System for susceptibility testing of S. pneumoniae. METHODS: One hundred clinical strains of S. pneumoniae (18 penicillin susceptible strains, 32 intermediate strains, and 50 resistant strains) were tested, which had been isolated in Samsung Medical Center. Minimum inhibitory concentrations (MICs) for penicillin, cefotaxime, erythromycin, ofloxacin, chloramphenicol, tetracyclin, and vancomycin were determined by broth dilution method and VITEK-2 System using AST-P506 cards. The results obtained by VITEK-2 System were compared to those obtained by broth dilution method. RESULTS: Overall agreement of MICs determined by two methods was 93.0% within the range of one dilution. The best agreement was achieved with vancomycin (100%), and in descending order, 99% with ofloxacin, 97% with erythromycin, 94% with chloramphenicol, 89% with cefotaxime, 88% with tetracycline, and 85% with penicillin. There were 1.9% of very major error, 2.0% of major error, and 8.6% of minor error. The mean time for generation of susceptibility results was 9.6 hours. CONCLUSIONS: VITEK-2 System provided rapid and reliable determinations of susceptibility category for most antibiotics and would be helpful as a substitution of existing MIC methods.

Distribution and Antibiotic Resistance of Escherichia coli in Hospital / 中华医院感染学杂志

OBJECTIVE To understand the distribution and antibiotic resistance of E.coli isolated from our hospital and offer suggestions for clinic.METHODS The antibiotic susceptibility to 21 kinds of antibiotics were tested by K-B method and analyzed by Whonet software.RESULTS The antibiotic resistance of 301 E.coli strains to ampicillin,quinolones,piperacillin,gentamicin,cefazolin,cefuroxime,ceftriaxone,ceftazidime,aztreonam,cefepime, ampicillin/sulbactam were 83.39%,69.44%,62.79%,44.19%,42.86%,36.88%,35.22%,31.23%,29.90%,29.57% and 26.91%,respectively.CONCLUSIONS E.coli isolated from our hospital show high resistance to several kinds of antibiotics.The drugs should be choosed reasonably according to their antibiotic suscepitibity results.