A Silent Threat of Emerging Resistance Based on Antifungal Susceptibility Pattern of Filamentous Fungi by Microdilution, E Test and, Disc Diffusion Method: A Critical Constructive Analysis

For more than two decades, antifungal susceptibility testing and interpretation haunted the medical professionals in diagnostics and management. This article mainly focuses on the three most widely used methods: broth microdilution, E test, and disc diffusion. It also focuses on the fact that clinicians should switch from empirical treatment to susceptible drugs as early as possible to combat antifungal resistance and newer mutations that horrify us every single day with poor patient outcomes. Many factors need to be taken into account during the interpretation of results but the positive side of the story is that they have been well documented in the literature. Though many methods have come up in testing antifungal susceptibility, still there is a scope for a rapid yet accurate testing modality to flourish and take the lead

Phenotypic detection of metallo-beta-lactamase production in clinical isolates of Escherichia coli and Klebsiella pneumoniae in a tertiary care hospital

Introduction: Carbapenem resistance due to metallo-beta-lactamase (MBL)-producing bacteria is an emerging threat worldwide. This study aimed to detect the MBL production in clinical isolates of E. coli and Klebsiella pneumoniae species in our hospital setting and to evaluate the efficiency of two phenotypic methods for the detection of MBL production. Materials and Methods: The present study was carried out in the Department of Microbiology, MGM Medical College and Hospital, Aurangabad, Maharashtra, for a period of 2 years from April 2018 to March 2020. From a total of 12,324 various clinical specimens, 393 isolates of E. coli and Klebsiella pneumoniae species were tested for MBL production. MBL was detected by two different phenotypic methods, i.e., combined disc test and E-test. Results: Out of 393 isolates, 130 (33.07%) isolates were resistant to imipenem on screening of which 71 (18.06%) were Klebsiella pneumoniae and 59 (15.01%) were E. coli. About 43.66% Klebsiella pneumoniae isolates and 40.67% E. coli isolates were MBL-positive by the combined disc test. Using the E-test, MBL production was found to be 46.47% and 45.76% in Klebsiella pneumoniae and E. coli, respectively. Conclusion: Routine screening of MBL-producing organisms should be performed in diagnostic laboratories to control the spread of resistance and for the proper management of antibiotic therapy. E-test is better than the combined disc test for the detection of MBL-producing gram-negative bacilli.

Bacteriemia por Staphylococcus aureus con sensibilidad disminuida heterogénea a vancomicina: reporte de un caso / Staphylococcus aureus bacteremia with heterogeneous intermediate-level vancomycin resistance: a case report

Staphylococcus aureusmeticilina-resistente (SAMR)es una causa frecuente de bacteriemias intrahospitalarias. Para su tratamiento se utiliza vancomicina y han emergido cepas con sensibilidad disminuida heterogénea (h-VISA) que albergan subpoblaciones con sensibi-lidad reducida a vancomicina. Se comunica un caso de bacteriemia intra-tratamiento con vancomicina por SAMR h-VISA. El aislamiento muestra sensibilidad a vancomicina (CIMvan: 1 µg/mL), sin embargo E-test GRD sugiere h-VISA (CIMvan: 2 µg/mL y CIMtei: 8 µg/mL). El análisis del perfil poblacional - área bajo la curva (PAP-AUC) valida este hallazgo. Se rota a linezolid con resolución clínica.

Methicillin-resistant Staphylococcus aureus (SAMR) is a common cause of nosocomial bacteremia. Vancomycin, a glycopeptide, is widely employed for the therapy of SAMR infections. In recent years, heterogeneous vancomycin-intermediate strains (h-VISA) have emerged. We report a case of intra-treatment bacteremia caused by SAMR h-VISA. The isolate shows susceptibility to vancomycin (MICvan: 1 µg/mL). But the GRD E-test suggests h-VISA (MICvan: 2 µg/mL and MICtei: 8 µg/mL). The population analysis profile - area under the curve (PAP-AUC) validates SAMR h-VISA. Rotation of antibiotic therapy with linezolid is done, with good clinical outcome.

Isolation, identification and antifungal susceptibility of Candida in patients with fungal sepsis

Background: In this study, our aim was to identify and isolate Candida species from patients admitted in ICU,s of our hospital and to determine their susceptibilities to various antifungal agents so as to find the local resistance pattern and guide for empirical treatment.Methods: In our study 37 strains of candida were isolated (4 Candida albicans, 33 Non-albicans Candida strains). Candida species were identified by conventional, biochemical and molecular methods. Antifungal susceptibility tests for amphotericin B, fluconazole, itraconazole, ketoconazole and voriconazole were performed with broth microdilution method and E- tests as described by National Committee for Clinical Laboratory Standards (NCCLS).Results: Out of 37 Candida strains, the most prevalent species were C. tropicalis (43.2%), C. parapsilosis (24.3%), C. krusei (16.2%), C. albicans (10.8%), and C. glabrata (2.7%). Among all strains four strains (10.8 %) were resistant, two Candida albicans where found resistant to fluconazole one Candida krusei and one Candida parapsilosis were found to be resistant to all azoles.Conclusions: Candidemia continues to be associated with substantial morbidity and mortality and non albicans Candida species are the commonly isolated pathogen from those patients admitted in tertiary care hospitals in Indian scenario. Thus, it is imperative to perform antifungal susceptibility to select appropriate and effective antifungal therapy.

Evaluation on the Accuracy of VITEK 2 Compact for the Susceptibility of Carbapenem-Resistant Klebsiella Peumoniae to Amikacin / 现代检验医学杂志

Objective To evaluate the accuracy of VITEK 2 Compact in the detection of the drug susceptibility of carbapenemresistant Klebsiella pneumoniae (CRKP) to Amikacin.Methods The susceptibility for 147 isolates of SRKP to Amikacin were detected by VITEK 2 Compact,disk diffusion method (K-B method) and E-test method,respectively.Results Among the 147 strains of Klebsiella pneumoniae,the drug susceptibility results were consistent between K B and E-test method.Among the 5 strains,the results were totally consistent by VITEK 2 Compact,K-B method and E test method,of which 4 strains were sensitive,1 strains were resistant.There were 142 strains being not consistent between VITEK 2 Compact and E-test method.The results of VITEK 2 Compact were sensitive or intermediate,while E test were drug resistance.Conclusion VITEK 2 Compact is not reliable for the detection of CRKP to Amikacin,which requires that K B method or other methods should be used for the susceptibility of CRKP to Amikacin.

Sensibilidad a los antimicrobianos de aislamientos de Helicobacter pylori aislados de lesiones gástricas / Antimicrobial susceptibility of Helicobacter pylori strains isolated from gastric lesions

Se evaluó la sensibilidad a los antimicrobianos de 30 aislamientos de Helicobacter pylori aislados de biopsias gástricas mediante los métodos de difusión por discos y tiras de E-test. Los antimicrobianos evaluados fueron amoxicilina, claritromicina, metronidazol y ciprofloxacina. No se encontraron cepas resistentes a amoxicilina, el 17% (5/30) fueron resistentes a claritromicina, el 20% (6/30) a ciprofloxacina por ambos métodos, y el 37% (11/30) a metronidazol por E-test. Si bien el número de cepas estudiadas fue reducido, hubo una sola discrepancia en la interpretación de la sensibilidad cuando se compararon ambos métodos: el metronidazol fue categorizado como sensible por E-test e intermedio por el método de difusión por discos. No pudo determinarse una asociación estadísticamente significativa entre el tipo de lesión histológica y el patrón de resistencia encontrado.

Antimicrobial susceptibility was evaluated by two diffusion methods: E-test strips to determine minimum inhibitory concentration (MIC) and disk diffusion for amoxicillin, clarithromycin, metronidazole and ciprofloxacin in 30 Helicobacter pylori strains isolated from gastric biopsies. No strains were resistant to amoxicillin, 17% (5/30) were resistant to clarithromycin, 20% (6/30) ciprofloxacin by both methods, and 37% (11/30) to metronidazole by the E-test. Although the number of strains studied was reduced, there was a single mismatch in interpreting susceptibility when both methods were compared; the same mismatch was observed for metronidazole, being categorized as sensitive by the E-test and as intermediate by disk diffusion. No association between the histological type of lesion and the resistance pattern found could be determined.

Design and simulation of computerized tumbling E test / 第二军医大学学报

Objective To design a new method for visual acuity test naming computerized tumbling E test, and to explore the application of computerized tumbling E test. Methods The feasibility of computerized tumbling E test was investigated by computer simulation experiment. Based on the simulation experiment, a total of 30 subjects ([26.1±4.7] years old, 18 males and 12 females) received binocular vision acuity examination by computerized tumbling E test with 40 trials or 80 trials and standard logarithmic visual acuity chart (random sequence), respectively. The accuracy of computerized tumbling E test was evaluated by comparing the consistency limit with standard logarithmic visual acuity chart. The correlation and difference between the two tests were evaluated by paired samples t test. Results There was no significant difference between the results of the computerized tumbling E test with 40 trials and standard logarithmic visual acuity chart, while the difference between the results of the 80 trials and standard logarithmic visual acuity chart was statistically significant (P<0.05). Conclusion The consistency is good for adult visual test using the computerized tumbling E test with reasonable number of trials (40 trials) and the standard logarithmic visual acuity chart. Compared with the standard logarithmic visual acuity chart, computerized tumbling E test has advantages such as avoiding the problem of optotype memory and reducing the visual crowding effect, showing practical application value (P<0.05) of optotype memory and reducing the visual crowding effect, showing practical application value (P

Susceptibility of Acinetobacter baumannii isolates to eight antimicrobial agents tested by different methods / 中国感染与化疗杂志

Objective The purpose of this study was to analyze the susceptibility profile of Acinetobacter baumannii to antimicrobial agents,and validate the results of different antimicrobial susceptibility testing methods,for improving the quality of antibiotic resistance monitoring data.Methods The susceptibility data of Hebei Provincial Antimicrobial Resistant Investigation Net were analyzed retrospectively and 126 strains ofA.baumannii were collected.The susceptibility ofA.baumannii to piperacillintazobactam,amikacin,gentamicin,ciprofloxacin,levofloxacin,ceftazidime,imipenem,and meropenem was tested by E-test,KirbyBauer method and VITEK system.Results The susceptibility results of the 126 A.baumannii strains showed that the susceptibility to piperacillin-tazobactam,amikacin,gentamicin,levofloxacin and ceftazidime was significantly different between the three methods (P＜0.05).The categorical agreement,major error,minor error,and very major error of Kirby-Bauer method were within acceptable range.There were evident difference in classification consistency for piperacillin-tazobactam,amikacin,levofloxacin between Kirby-Bauer method and VITEK (P＜0.05).Conclusions Different antimicrobial susceptibility testing methods may lead to different results of resistance monitoring data.Bias may be generated in antibiotic resistance surveillance if different methods are used.The susceptibility results of piperacillin-tazobactam,amikacin,levofloxacin derived from VITEK system should be validated by Kirby-Bauer or E-test method.

Prevalence and Clinical Impact of Heterogeneous Vancomycin-Intermediate Staphylococcus aureus Isolated From Hospitalized Patients

BACKGROUND: We estimated the prevalence and clinical impact of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA). The concordance between macromethod and glycopeptide resistance detection (GRD) E tests was determined. In addition, predictors of clinical outcomes in hospitalized patients with S. aureus bacteremia (SAB) or pneumonia (SAP) were evaluated. METHODS: We obtained 229 consecutive S. aureus isolates from all hospitalized patients at two university hospitals located in Busan and Yangsan, Korea. Standard, macromethod, and GRD E tests were performed. Additionally, we reviewed the medical records of all patients. Among the 229 patients, predictors of clinical outcomes were analyzed for 107 patients with SAB and 39 with SAP. RESULTS: Among the 229 isolates, 34.5% of S. aureus isolates and 50.7% of methicillin-resistant S. aureus isolates exhibited the hVISA phenotype based on the macromethod E test. hVISA was nearly associated with treatment failure in patients with SAB (P=0.054) and was significantly associated with treatment failure in patients with SAP (P=0.014). However, hVISA was not associated with 30-day mortality in patients with SAB or SAP. The concordance between the macromethod and GRD E tests was 84.2%. CONCLUSIONS: hVISA is quite common in the southeastern part of Korea. hVISA is associated with treatment failure in patients with SAP.

Ocular infections caused by Candida species: Type of species, in vitro susceptibility and treatment outcome.

Purpose: To report clinical and microbiological profile of patients with ocular candidiasis. Materials and Methods: Patients with ocular candidiasis were retrospectively identified from microbiology records. Significant isolates of Candida species were identified by Vitek 2 compact system. Minimum inhibitory concentration (MIC) of antifungal agents such as amphotericin B, itraconazole, voriconazole, fluconazole and caspofungin was determined by E test and of natamycin by microbroth dilution assay. Data on treatment and outcome were collected from medical records. Results: A total of 42 isolates of Candida were isolated from patients with keratitis-29, endophthalmitis-12 and orbital cellulitis-1. The most common species isolated was Candida albicans (12-keratitis, 4-endophthalmitis, 1-orbital cellulitis). All except one isolate were susceptible to amphotericin B. MIC of caspofungin was in the susceptible range in 28 (96.5%) corneal isolates while 12 out of 29 (41.3%) corneal isolates were sensitive to fluconazole. Resistance to voriconazole was seen in four corneal isolates. All isolates were susceptible to natamycin and all except two isolates were resistant or susceptible dose-dependent to itraconazole. Outcome of healed ulcer was achieved in 12/18 (66.6%) patients treated medically, while surgical intervention was required in 11 patients. Among the isolates from endophthalmitis patients, 11/12 were susceptible to amphotericin B, 6/12 to voriconazole and all to natamycin. Ten out of 11 patients (one patient required evisceration) with endophthalmitis were given intravitreal amphotericin B injection with variable outcome. Conclusions: Ocular candidiasis needs early and specific treatment for optimal results. Candida species continue to be susceptible to most commonly available antifungals including amphotericin B, voriconazole and natamycin.

Phenotypic speciation of enterococci with special reference to prevalence, virulence and antimicrobial resistance.

Background: Now considered as one of the most important Nosocomial pathogen, enterococci have been found to possess virulence factors like biofilm formation and are increasingly exhibiting antimicrobial resistance in India. This study was undertaken to estimate the prevalence of enterococci from various clinical samples simultaneously correlating their virulence property and antimicrobial resistance, in addition to speciation. Methods: A total of 126 enterococcal isolates from various clinical samples were included and processed according to standard protocols and speciation was based on Facklam and Collins conventional method. Virulence determinants like hemolysin, gelatinase and biofilm formation were assessed by phenotypic tests. Antibacterial susceptibility pattern was determined by Kirby Bauer disc diffusion method with recommended drugs including high level aminoglycoside resistance. Minimum inhibitory concentration (MIC) for vancomycin was done by E-test. Results: Out of 1746 clinical samples, enterococci accounted for 7.22%. They consisted of E. faecium 52.38%, E. faecalis 32.54%, and E. avium 15.08% isolated from urine 8.26%, pus 8.44%, blood 0.56% and body fluids 1.28%. Study on virulence factors revealed that 19.84% strains produced gelatinase, 18.25% produced hemolysin and 73.81% produced biofilm. High level resistance to gentamycin and streptomycin were 4.76% and 5.56% respectively. Vancomycin resistance was 3.17%. Conclusions: This study indicates the change in epidemiology of enterococcal infections from E. faecalis to E. faecium and low prevalence of vancomycin resistant enterococcus (VRE) in our region. To maintain the low level of resistance, improvement of antibiotic policies and hospital infection control is essential.

Pattern of susceptibility to azoles by E test method in candidemia patients.

Background: Blood stream infections due to Candida sp have considerably increased in recent years, along with the increase of drug-resistant isolates in immunocompromised patients. This increase in resistance makes it important to determine the antifungal susceptibility profile of each Candida species isolated from blood prior to treatment. Hence, this study was done to detect the resistant strains of Candida causing candidemia. Methods: About Seventy Candida species isolated from blood cultures were used for this study. These included 27 Candida albicans, 23 Candida tropicalis, 8 Candida parapsilosis, 3 Candida krusei, 2 Candida glabrata and 7 other candida species. Minimum inhibitory concentrations (MIC) of the most commonly used azoles like fluconazole, ketoconazole, itraconazole and voriconazole were determined by E test method. Results: The resistance percentage of Candida albicans for fluconazole and itraconazole was 11.1% and 7.4%; fluconazole resistance in Candida tropicals was 8.7%. Candida parapsilosis had good activity against all azoles with only 12.5% resistance for itraconazole. Conclusions: Fluconazole had good activity against most of the Candida sp except for Candida glabrata and Candida krusei with MIC 90 > 256 μg/ml. Itraconazole was less effective for Candida albicans, Candida glabrata and Candida parapsilosis (MIC 90 >32 μg/ml). Voriconazole was found to be the most effective drug against all species of Candida with low MIC values (MIC 90 < 0.25 μg/ml). Hence it can be used to treat blood stream infections caused by Candida species.

Antimicrobial susceptibility testing for Helicobacter pylori isolates from Brazilian children and adolescents: comparing agar dilution, E-test, and disk diffusion

Antimicrobial susceptibility testing for Helicobacter pylori is increasingly important due to resistance to the most used antimicrobials agents. Only agar dilution method is approved by CLSI, but it is difficult to perform routinely. We evaluated the reliability of E-test and disk diffusion comparing to agar dilution method on Helicobacter pylori antimicrobial susceptibility testing. Susceptibility testing was performed for amoxicillin, clarithromycin, furazolidone, metronidazole and tetracycline using E-test, disk-diffusion and agar dilution method in 77 consecutive Helicobacter pylori strains from dyspeptic children and adolescents. Resistance rates were: amoxicillin - 10.4%, 9% and 68.8%; clarithromycin - 19.5%, 20.8%, 36.3%; metronidazole - 40.2%33.7%, 38.9%, respectively by agar dilution, E-test and disk diffusion method. Furazolidone and tetracycline showed no resistance rates. Metronidazole presented strong correlation to E-test (r = 0.7992, p < 0.0001) and disk diffusion method (r=-0.6962, p < 0.0001). Clarithromycin presented moderate correlation to E-test (r = 0.6369, p < 0.0001) and disk diffusion method (r=-0.5656, p < 0.0001). Amoxicillin presented weak correlation to E-test (r = 0.3565, p = 0.0015) and disk diffusion (r=-0.3565, p = 0.0015). Tetracycline presented weak correlation with E-test (r = 0.2346, p = 0.04) and furazolidone to disk diffusion (r=-0.0288, p = 0.8038). E-test presented better agreement with gold standard. It is an easy and reliable method for Helicobacter pylori susceptibility testing. Disk diffusion method presented high disagreement and high rates of major errors.

Determination of Vancomycin and Methicillin Resistance in Clinical Isolates of Staphylococcus aureus in Iranian Hospitals.

Aims: The aim of this study was to determine the prevalence of methicillin resistant S. aureus (MRSA), vancomycin resistant or vancomycin intermediate resistant S. aurues (aureus) (VRSA/VISA) among clinical isolates. Study Design: S.aureus isolates used in this study were randomly collected from in-patient and outpatient of several hospitals of 7 cities in Iran (Tehran, Shiraz, Zahedan, Tabriz, Sannandaj, Sari, and Ahvaz) during 2006-2008. Methodology: Antibiotic susceptibility of 250 strains of Staphylococcus aureus isolated from Iranian hospitals were determined by disk diffusion method. Minimum inhibitory concentration (MICs) were determined for oxacillin and vancomycin by E-test. PCRs were used by specific primers (PCR used specific primers) for detection of mecA, vanA, vanB genes. Results: The percentage of resistance by disk diffusion method was as below: methicillin 46%, vancomycin 0%, penicillin 86%, erythromycin 42%, ciprofloxacin 29%, gentamicin 39% and clindamycin 33%. E-test MIC method showed that 43% isolates were resistant to methicillin and 4% isolates were VISA (≤ 8μg/ml). The prevalence of resistance genes in the clinical isolates were: mecA 44%, vanA 0%, vanB 0%. Conclusion: This study revealed that clinical isolates have rather high resistance to methicillin, erythromycin, gentamicin, penicillin and clindamycin We did not observe resistance to vancomycin. In order to avoid a possible outbreak involving VISA), vancomycin should be used carefully as a drug for treatment of S. aureus infections.

Comparative evaluation of disk diffusion and E-test methods for clarithromycin susceptibility testing of Helicobacter pylori / 中华临床感染病杂志

Objective To compare disk diffusion with E-test methods for clarithromycin susceptibility testing of Helicobacter pylori (H.pylori).Methods A total of 44 strains of H.pylori were isolated from gastric mucosa biopsy from patients undergoing gastroscopic examination.Disk diffusion and E-test methods were used for clarithromycin susceptibility testing of H.pylori.The agreement of disk diffusion and E-test was assessed by linear regression analysis.Results The minimum inhibitory concentration (MIC) tested by E-test method ranged from 0.016 to 256 μg/mL,and drug resistance was observed in 12(27.3％) isolates.In range of 0-35 mm of inhibition diameter,the results of disk diffusion method were correlated well with the MICs obtained by E-test method (r2 =0.91,P ＜0.01).Regression analysis showed that with inhibition diameters≥ 18 mm as considered sensitive to clarithromycin and ≤ 15 mm as resistant,the agreement was 100％ between two methods.Conclusion The disk diffusion method is equivalent to the E-test method for clarithromycin susceptibility testing of H.pylori,which can be an alternative method for clinical application.

Antimicrobial susceptibility profile of brucella spp. isolated in Brazil

The intention of this work was to investigate the susceptibility profile of 27 Brucella strains isolated from animals in Brazil, using the E-test method with antimicrobials recommended for the treatment of human brucellosis, to monitor the activities of these antimicrobials and their potential efficacy for human brucellosis treatment. Efficiency of SE-AFLP in determining the genetic diversity of the species of Brucella and its correlation with their susceptibility profile was also evaluated. All 27 strains were susceptible to doxycycline. With the exception of one strain of B. canis and of B. abortus, all strains were susceptible to gentamicin and streptomycin. Of the wild Brucella strains tested, ten, nine and five showed reduced susceptibility to rifampicin, ceftriaxone and trimetoprim/sulfamethoxazole, respectively. One B. abortus and three B. canis strains showed multi-resistance profiles. The strain of B. abortus was resistant to streptomycin, rifampicin and ceftriaxone. Two strains of B. canis were resistant to rifampicin, ceftriaxone and trimetoprim/sulfamethoxazole, and one strain was resistant to rifampicin, ceftriaxone, streptomycin and gentamicin. Rifampicin, in combination with doxycycline, is one of the principal antibiotics prescribed to treat human brucellosis. The occurrence of strains resistant to rifampicin and other antimicrobials must be monitored before initiating this treatment, since the resistance of these strains could be one of the causes of the failure of some brucellosis treatment. No relationship was observed between SE-AFLP profiles and regional origin of the strains; neither between SE-AFLP profiles and antimicrobial profiles...

O objetivo deste trabalho foi investigar o perfil de susceptibilidade de 27 cepas de Brucella isoladas de animais no Brasil, utilizando-se o método E-test com os antimicrobianos recomendados para o tratamento da brucelose humana. Com este método, pretendeu-se monitorar a atividade destes antimicrobianos e seu potencial de eficacidade no tratamento desta enfermidade no homem. Também foi avaliada a eficiência da técnica SE-AFLP para discriminar as diferentes cepas de Brucella sp. e para analisar se os perfis gerados mostram alguma relação com os resultados de susceptibilidade. Todas as 27 cepas testadas foram sensíveis à doxiciclina, com exceção de uma cepa de B. canis e outra de B. abortus; as demais cepas foram sensíveis à gentamicina e à estreptomicina. Do total de cepas de campo testadas, respectivamente, dez, nove e cinco apresentaram susceptibilidade reduzida à rifampicina, ceftriaxona e trimetoprim/sulfametoxazol. Uma cepa de B. abortus e três de B. canis apresentaram perfil de multirresistência. A cepa de B. abortus mostrou-se resistente à estreptomicina, rifampicina e ceftriaxona. Duas cepas de B. canis foram resistentes à rifampicina, ceftriaxona e trimetoprim/sulfametoxazol e uma cepa foi resistente à rifampicina, ceftriaxona, streptomicina e gentamicina. Rifampicina e doxiciclina, associadas, são os principais antibióticos recomendados para o tratamento da brucelose humana. A ocorrência de cepas resistentes à rifampicina e outros antimicrobianos deve ser monitorada antes do início do tratamento, pois a resistência a esses antimicrobianos pode ser uma das causas do insucesso de alguns tratamentos de brucelose. Não foi observada nenhuma correlação entre os perfis SE- AFLP gerados e a origem das cepas, nem com os perfis de susceptibilidade destas cepas...

Antimicrobial susceptibility of Neisseria gonorrhoeae isolates from patients attending a public referral center for sexually transmitted diseases in Belo Horizonte, State of Minas Gerais, Brazil

Introduction The aim of this study was to determine the antimicrobial susceptibility of Neisseria gonorrhoeae isolates obtained from patients attending a public referral center for sexually transmitted diseases and specialized care services (STD/SCS) in Belo Horizonte, Brazil. Methods Between March 2011 and February 2012, 201 specimens of Neisseria gonorrhoeae were consecutively obtained from men with symptoms of urethritis and women with symptons of cervicitis or were obtained during their initial consultation. The strains were tested using the disk diffusion method, and the minimum inhibitory concentrations of azithromycin, cefixime, ceftriaxone, ciprofloxacin, chloramphenicol, penicillin, tetracycline and spectinomycin were determined using the E-test. Results The specimens were 100% sensitive to cefixime, ceftriaxone and spectinomycin and exhibited resistances of 4.5% (9/201), 21.4% (43/201), 11.9% (24/201), 22.4% (45/201) and 32.3% (65/201) to azithromycin, ciprofloxacin, chloramphenicol, penicillin and tetracycline, respectively. Intermediate sensitivities of 17.9% (36/201), 4% (8/201), 16.9% (34/201), 71.1% (143/201) and 22.9% (46/201) were observed for azithromycin, ciprofloxacin, chloramphenicol, penicillin and tetracycline, respectively. The specimens had plasmid-mediated resistance to penicillin PPNG 14.5% (29/201) and tetracycline TRNG 11.5% (23/201). Conclusions The high percentage of detected resistance to penicillin, tetracycline, chloramphenicol and ciprofloxacin indicates that these antibiotics are not appropriate for gonorrhea treatment at the Health Clinic and possibly in Belo Horizonte. The resistance and intermediate sensitivity of these isolates indicates that caution is recommended in the use of azithromycin and emphasizes the need to establish mechanisms for the surveillance of antimicrobial resistance for the effective control of gonorrhea. .

Combined antimicrobial susceptibility test against pan-drug-resistant Acinetobacter baumannii with E-test and microdilution checkerboard assay / 中华微生物学和免疫学杂志

Objective To evaluate the activity of antibiotics against pan-drug-resistant (PDR) Acinetobacter baumannii by combination antimicrobial susceptibility test in viro with epsilometric methods (Etest method) and microdilution checkerboard (CB method),and to detect a good correlation between timekill curve with the above mentioned two assays.Methods Thirty-one clinical isolates of PDR Acinetobacter baumannii were selected for mono and combination antimicrobial susceptibility test in vitro by E-test and CB method,then a comparison was conducted between the test results and the time-kill curve.Mono drugs involved tigecycline,colistin,imipenem and amikacin,and combinations involved two of drugs above,and three drugs involved imipenem/tigecycline,plus amikacin combination.Results Synergistic effect was detected in imipenem plus colistin and tigecycline plus imipenem combination.A high comparability was revealed between the E-test method with antimicrobial drugs added into the culture medium and the time-kill curves.Synergy in the combination of imipenem/tigecycline,plus amikacin was detected by the CB method and time-kill curves.Conclusion The results showed that the effect of specific combination of antibiotics against PDR Acinetobacter baumannii could be predicted by testing their synergistic effect with combination antimicrobial susceptibility test.

A Study on Anlaysis of Patch Test Positive Reactivity according to the Reading Time with T.R.U.E. TEST(R) / 대한피부과학회지

BACKGROUND: The patch test is widely used for diagnosis of allergic contact dermatitis. However, nearly half of positive reactions can be observed only on day 2 or day 4 and it is difficult to interpret these reactions. OBJECTIVE: The purpose of this study is to assess the frequency of transient and delayed reactions in TRUE-test and detect common antigens that provoke these reactions. METHODS: A total of 311 patients with allergic contact dermatitis were evaluated by TRUE-test between Jan 2007 and December 2011. Records of patch test results of day 2 and day 4 were reviewed and analyzed. RESULTS: A total 311 cases of T.R.U.E. TEST(R) records (male 79, female 232) were analyzed. Persistent reactions were observed in 80.1% patients tested, transient reactions were observed in 18.3%, and delayed reaction in 5%. Frequent allergens which showed transient reactions were cobalt dichloride (2.9%), nickel sulfate (2.2%), thiomersal (1.9%), and carba mix (1.6%), in order of frequency. Allergens which showed delayed reactions were nickel sulfate (0.3%), fragrance mix (0.3%), p-tert-butylphenol formaldehyde resin (0.43). CONCLUSION: Our results showed a relatively high frequency of transient reaction in T.R.U.E. TEST(R). This suggests that additional reading at day 4 in the patch test would be of value.