Investigation of in vitro antifungal susceptibility testing and genetic diversity of clinical isolates of Trichophyton benhamiae and Trichophyton eriotrephon in Iran.

BACKGROUND: Trichophyton benhamiae is a zoophilic dermatophyte, known as one of the causative agents of dermatophytosis. OBJECTIVES: The purpose of this study was to explore the genotypes of T. benhamiae strains isolated from geographically different areas of Iran and also to evaluate in vitro antifungal susceptibility profile of these strains against seven antifungal drugs. METHODS: Twenty-two strains of T. benhamiae and two strains of T. eriotrephon were isolated from patients with distinct types of dermatophytosis. DNA extraction and amplification of rDNA regions using ITS1 and ITS4 primers were conducted on the isolates. The in vitro antifungal susceptibility of posaconazole (PSC), voriconazole (VRC), itraconazole (ITC), ketoconazole (KET), caspofungin (CAS), terbinafine (TRB) and griseofulvin (GRZ) was evaluated according to CLSI M38-A2 protocol. RESULTS: The multiple alignment of the ITS-rDNA sequences of T. benhamiae indicated a mean similarity of 99.5%, with 0-3 interspecies nucleotide difference. The geometric mean (GM) values of minimum inhibitory concentrations (MICs) and minimum effective concentrations (MECs) across the all isolates were respectively: TRB: 0.025 mg/L, PSC: 0.032 mg/L, ITC: 0.050 mg/L and VRC: 0.059 mg/L with lower values and CAS: 0.31 mg/L, KTZ: 0.56 mg/L and GRZ: 0.76 mg/L with higher values. CONCLUSION: Diverse ITS sequence types of T. benhamiae were shown in different geographical regions of Iran. The TRB, PSC and ITC were the most effective drugs against T. benhamiae strains, respectively. Furthermore, in our study, two strains of T. eriotrephon as a scarce dermatophyte species were described.

Microorganisms and Antibiogram Patterns in Fournier's Gangrene: Contemporary Experience from a Single Tertiary Care Center.

PURPOSE: We evaluate the prevalent microorganisms, antibiotic sensitivity patterns and associated outcomes in patients with Fournier's gangrene. MATERIALS AND METHODS: A retrospective chart review of patients with Fournier's gangrene was conducted between October 2011 and April 2018 at our institution. Univariate analysis was performed using the independent t-test or Kruskal-Wallis H test for continuous variables and exact test for categorical variables. RESULTS: Of the 143 patients included in this study, wound culture was available in 131 (92%) patients with a median number of 3 microorganisms per wound. The most commonly grown pathogens were Staphylococcus species (66, 46%), Streptococcus species (53, 37%), Bacteroides species (34, 24%), Candida species (31, 22%), Escherichia coli (28, 20%) and Prevotella species (26, 18%). Most bacteria were sensitive to ampicillin-sulbactam, ceftriaxone, piperacillin-tazobactam, amikacin and cefepime, and resistant to ampicillin, trimethoprim-sulfamethoxazole, levofloxacin and clindamycin. Enterococcus faecalis and Streptococcus anginosus were resistant to vancomycin. The overall Fournier's gangrene mortality count was 14 (10%) patients. No association was noted between the type of infection and Fournier's gangrene severity index, length of hospital stay or mortality. CONCLUSIONS: At our institution Candida is a prevalent pathogen in the wound culture of patients with Fournier's gangrene. The resistance patterns for clindamycin and vancomycin are concerning. Addition of an antifungal agent to the empiric treatment should be considered based on clinical presentation.

Antimicrobial activity of different solvent extracted samples from the leaves and fruits of Capsicum annuum.

The current research describes the antimicrobial potential of methanol, n-hexane, n-butanol, ethyl acetate and aqueous extracted samples from the leaves and fruits tissues of Capsicum annuum. Different solvent extracted samples were screened against six pathogenic microorganisms including five bacterial and one fungal specie by disc diffusion susceptibility assay using 1, 2 and 3 mg disc-1 concentrations. When analyzed statistically the data showed that different solvent extracted samples from both leaves and fruits of Capsicum annuum revealed varying degrees of antibacterial and antifungal activities. n-butanol and ethyl acetate extracted fractions from both leaves and fruits showed significant inhibition of growth against all the tested microorganisms at 1, 2 and 3 mg disc-1 concentrations. Escherichia coli were completely resistant to aqueous extracts obtained from the leaves at all the three concentrations. Klebsiella pneumonia was resistant to n-hexane extracted fraction from leaves at 1mg disc-1 concentration, however, was susceptible at 2 and 3 mg disc-1 concentrations. The growth of Pseudomonas aeruginosa and Staphylococcus aureus were effectively inhibited by all the solvent extracted fractions from the fruits while aqueous fraction was not able to inhibit the growth of Bacillus subtilis. The growth of Candida albicans was effectively inhibited by ethyl acetate extracted fraction from leaves at 3 mg disc-1 concentration.

Antibacterial and antibiofilm activities of Scorzonera mackmeliana.

Scorzonera have been confirmed to have potent bioactivity. Scorzonera mackmeliana (Asteraceae), the endemic plant to Lebanon, has not yet been investigated. In the present study, we assessed the antibacterial activity of S. mackmeliana extracts against referenced bacterial strains. Extracts from different parts of the plant were evaluated against Staphylococcus, Enterococcus, Escherichia and Pseudomonas species. Phytochemical screening was done by standard biochemical tests and minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC) and minimal biofilm eradication concentration (MBEC) were determined by micro dilution method. The extracts possessed mainly alkaloids, phenols, flavonoids and coumarins. Gram-negative bacteria were most sensitive, whose MICs ranged between 48.98 and 341.85 mg/ml. Water stems extract, rich in phenols, was the most active with an MIC of 48.98 mg/ml. MBC was only recorded for water flowers extract, rich in resins, against P. aeruginosa and ethanolic roots extract, rich in terpenoids, against S. epidermidis with values of 160.85 mg/ml and 284.35 mg/ml, respectively. Furthermore, antibiofilm activity showed that the lowest MBEC was 0.1 mg/ml for water stems extract with an eradication ability of 91% (p <0.0001). Hence, this study suggests S. mackmeliana as a promising candidate for future investigations to elucidate the major bioactive compound behind the antibacterial and antibiofilm effect.

New Antifungal Susceptibility Test Based on Chitin Detection by Image Cytometry.

The antifungal susceptibility tests used in clinical laboratories have several limitations. We developed a new test, SensiFONG, based on the detection of chitin levels after exposure to antifungal drugs. The optimal culture conditions were 30°C for 6 h for yeast strains and 26°C for 16 h for molds. The strains were exposed to a range of echinocandin or azole concentrations. Chitin was stained with calcofluor white. The percentage of fungal cells with high chitin levels was determined with an automatic epifluorescence microscope. The SensiFONG results were compared to those with the EUCAST method. Image acquisition and analysis were performed with ScanR software. Fifty-nine strains (28 Candida albicans, 17 Candida glabrata, and 14 Aspergillus fumigatus) were analyzed. Thresholds for the classification of strains as resistant or susceptible were determined for each fungal species. The strains displaying an increase in chitin content of ≥32% for C. albicans, ≥6% for C. glabrata, and ≥17% for A. fumigatus were considered susceptible. The application of these thresholds to all 59 strains resulted in a sensitivity of 0.87, 0.93, and 1.00 and a specificity of 0.93, 0.84, and 0.82 for C. albicans, C. glabrata, and A. fumigatus, respectively. The correlation between the results obtained in the SensiFONG and EUCAST assays was excellent. We developed a new test, SensiFONG, based on a new concept. While current assays assess growth inhibition, our test detects changes in chitin levels after exposure to antifungal drugs. Here, we present preliminary results and we propose a proof of concept of this methodology.

No global increase in resistance to antibiotics: a snapshot of resistance from 2001 to 2016 in Marseille, France.

Since effective empirical antibiotic therapy is a key factor for survival, local antibiotic resistance epidemiology is critical. We aimed to identify current trends in antibiotic resistance for key antibiotics obtained over 16 years (2001-2016) for invasive infections corresponding to empirical treatment in a large hospital centre in Marseille, France.From January 2014 to December 2016, we have collected all data on antibiotic susceptibility from public laboratory hospitals, and a retrospective analysis was performed on key antibiotics in blood cultures since 2001. A total of 99,932 antibiotic susceptibility testings (ASTs) were analysed, and proportion of pan-drug resistant (PDR = resistant to all antibiotics tested) and extensively drug-resistant (XDR = resistant to all except for two classes) strains were < 0.03 and 0.5%, respectively. Between 2001 and 2016, we found an increase of resistance to third-generation cephalosporins for E. coli invasive strains (0% vs 17.8%; p < 10-5) and K. pneumoniae (8% vs 35.4%; p = 0.001) along with a decrease of methicillin-resistant S. aureus strains (31% vs 19.8%; p = 0.006). Moreover, during the 3-year period, a significant increase of wild-type strains, susceptible to all antibiotics tested, was observed in invasive infections. Regarding bacteraemia involving Enterobacteriaceae and S. aureus, empirical therapy is effective in > 99% cases. Active epidemiological surveillance is necessary because antibiotic resistance remains unpredictable.

Helicobacter pylori antimicrobial resistance during a 5-year period (2013-2017) in northern Spain and its relationship with the eradication therapies.

BACKGROUND: Antibiotic resistance is the main cause for Helicobacter pylori therapy failure. Frequently, empirical regimens have been recommended in patients with various H. pylori eradication failures. In patients with H. pylori-resistant to various families of antibiotics, the treatment guided by antimicrobial susceptibility testing allows the achievement of good eradication rates. AIM: To evaluate the effectiveness of susceptibility-guided antimicrobial treatment for H. pylori infection in patients with resistance to one or various families of antibiotics. METHODS: A total of 3170 consecutive patients infected by H. pylori during 2013-2017 were tested for antimicrobial susceptibility. 66.6% patients showed resistance to one antimicrobial, 18.9% to two, and 2.4% to three families of antibiotics. A cohort of 162 H. pylori-positive patients were enrolled in this study. Forty-three with single H. pylori resistance to clarithromycin (CLR) were treated with omeprazole (PPI), amoxicillin (AMX), and levofloxacin (LVX)-OAL (31 subjects) or omeprazole, AMX, and metronidazole (MTZ)-OAM (12 patients) and 77 patients with dual H. pylori resistance (51 to CLR and MTZ, 12 to CLR plus LVX, and 14 to MTZ plus LVX) received OAL or OBTM (PPI, bismuth subcitrate, tetracycline, and MTZ), OAM, and OAC, respectively. Other 42 patients with triple H. pylori resistance (CLR, LVX, and MTZ) were treated with PPI, AMX, and rifabutin-OAR (18 subjects), PPI, AMX, and doxycycline-OAD (8), OADB (7), OBTM (6), and ODBR (3). All subjects received standard doses for 10 days. Eradication rate was confirmed by 13 C-UBT. Adverse events were assessed by a questionnaire. RESULTS: Intention-to-treat analysis demonstrates that eradication rates using triple therapies in patients with H. pylori resistance to one and to two families of antibiotics were 93% and 94.8%, respectively. In subjects with H. pylori-resistant to three families of antibiotics, cure rate was higher in naïve patients treated with OAR-10 days compared to those treated with bismuth-containing quadruple therapies (90% vs 75%). Adverse events were limited (18 of 162, 11.1%), all of them mild-moderate. CONCLUSIONS: The implementation of susceptibility-guided triple therapy for 10 days leads to eradication rate ≥95% in naïve patients with H. pylori resistance to one or two families of antimicrobials. In naïve patients with H. pylori resistance to three families, OAR treatment achieved a 90% of eradication.

The epidemiology and management of candidemia in Northern Ireland during 2002-2011, including a 12-month enhanced case review.

In Northern Ireland there are concerns about candidaemia, with rates higher than those reported in England and Wales. Our aim was to explore the epidemiology of candidaemia during a 10 year period and the clinical management upon suspicion of cases during a one year enhanced investigation in Northern Ireland.Candidaemia reports to the Public Health Agency were validated during 2002-2011 and used to examine incidence and antifungal sensitivity trends (during 2007-2011). A clinical proforma was used to collate information for all patients with candidaemia in 2011.The majority (96%) of isolates were captured through voluntary laboratory reporting. There was a year-on-year increase in candidaemia from 2002-2011, from 80 to 131 episodes (incidence rate ratio 1.09 95% CI 1.05-1.13). Rates were highest in males under 1 year and over 75 years. 83/98 (85%) of case notes were available from candidaemia patients during 2011. The most prevalent risk factors were patients on total parenteral nutrition (26 people, 31.3%), surgery in the two months prior to the candidaemia (25 people, 30.1%), significant steroid use in the previous 3 months (24 people, 28.9%) and active neoplastic disease (23 people, 27.7%),This study confirmed an increase in candidaemia rates over time, with the observed incidence in 2011 higher than England and Wales. We identified areas for improvement around the clinical management of candidaemia. We recommend raising the awareness of guidelines for fundoscopy, echocardiography and central venous catheter removal.

Is a single set of negative blood cultures sufficient to ensure clearance of bloodstream infection in patients with Staphylococcus aureus bacteremia? The skip phenomenon.

BACKGROUND: The most recent version of the Infectious Diseases Society of America guidelines for the treatment of methicillin-resistant Staphylococcus aureus infections states that a single set of negative blood cultures is sufficient to demonstrate clearance of bacteremia. However, S. aureus might exhibit fluctuating blood culture positivity, labeled as "the skip phenomenon". Our objectives were to determine the prevalence of the skip phenomenon in a cohort of hospitalized patients with S. aureus bacteremia and to determine the associated clinical variables. METHODS: We conducted a nested case-control study, using a previous cohort of 757 adult inpatients between July 2006 and June 2011 with ≥ 3 days of S. aureus bacteremia. Each case of S. aureus bacteremia with the skip phenomenon was matched to 2 to 4 controls based on age, gender, and duration of bacteremia. The association of clinical characteristics with the skip phenomenon was analyzed via conditional logistic regression. RESULTS: Of the 757 patients in the cohort, 29 (4%) had the skip phenomenon. 26 (90%) patients in the cases group were male. The median age was 69.4 years (interquartile range [IQR] 58.7 to 80.3). Although an attempt to match for the duration of bacteremia was done, there was a statistically longer duration in patients with cases as compared to that in controls (median [IQR], 10 [7-12] days, vs 8 [6-10] days; P = 0.015). Accordingly, duration of bacteremia was adjusted for in regression models. Notably, 26 (90%) patients in the case group were receiving chronic immunosuppressive therapy, as compared to 69 (79%) patients in the control group (P = 0.427). CONCLUSION: Our findings prompt consideration of a practice chance to obtain serial negative blood cultures to ensure clearance of bacteremia among patients with S. aureus bacteremia.

Antimicrobial effects of cinnamon essential oil and cinnamaldehyde combined with EDTA against canine otitis externa pathogens.

AIMS: The antimicrobial activity of cinnamon essential oil and cinnamaldehyde against bacterial and fungal pathogens associated with canine otitis externa, as well as the effect of their combination with EDTA were investigated. METHODS AND RESULTS: Antimicrobial susceptibility testing was performed using the broth microdilution method while spot-plating technique was used to determine their bactericidal activity. Time-kill kinetics and checkerboard assays were performed to confirm the bactericidal activity and combination effects of the compounds. Cinnamon oil and cinnamaldehyde exhibited antimicrobial activity against Gram-positive and Gram-negative pathogens, as well as Malassezia pachydermatis. Synergistic interaction was shown when EDTA (672 µg ml-1 ) was combined with cinnamon oil (41 µg ml-1 ) and cinnamaldehyde (22 µg ml-1 ) against Pseudomonas aeruginosa. Cinnamaldehyde exhibited significantly stronger antimicrobial activity than cinnamon bark oil. CONCLUSIONS: Cinnamon essential oil and cinnamaldehyde, either used alone or in combination with EDTA, were effective against the causative micro-organisms of canine otitis externa. The data suggest that cinnamaldehyde could be a promising antimicrobial agent against canine otitis externa. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows that cinnamon essential oil and cinnamaldehyde, especially the latter, could be used in combination with EDTA as novel treatment for sensitive and resistant bacterial and fungal pathogens involved in canine otitis externa.

Synergy Testing by E-Test and Microdilution Checkerboard for Fosfomycin Combined with Tigecycline against KPC-Producing Klebsiella pneumoniae.

BACKGROUND: KPC-producing Klebsiella pneumoniae (KPC-Kp) has become a serious threat to patients worldwide, as the treatment options are limited. The combination of fosfomycin with other antibiotics has been reported but with inconsistent results. Thus, we performed synergy testing of fosfomycin combined with tigecycline by E-test, which was easy to perform and to determine results, compared with microdilution checkerboard, which is considered to be the "gold standard", to evaluate the agreement between the two methods. METHODS: Thirty non-repetitive KPC-Kp isolates from different patients were included in this study. Bacterial identification and routine antibiotic susceptibility testing were performed by a VITEK 2 Compact automated system. The KPC producing isolates were identified by modified Carbapenem Inhibitory Method (mCIM) and PCR amplification of carbapenemase genes. Synergy testing of fosfomycin combined with tigecycline was performed by E-test (E-test stripes were placed at 90° angle), with microdilution chequerboard performed in parallel. Fractional inhibitory concentration index (FICI) was calculated. Statistical analyses were performed by SPSS 18.0 software. RESULTS: All 30 KPC-Kp were mCIM test positive and KPC-2 producing. The susceptibility rates of fosfomycin and tigecycline were 36.7% (11/30) and 63.3% (19/30), respectively. Both checkerboard and E-test results showed that most MICs of fosfomycin and tigecycline decreased in the combination group. FICI showed 13.3% - 16.7% isolates were synergistic, 30.0% - 36.7% were additive, and 50.0% - 53.3% were indifferent. No antagonism was found. There was no significant difference between the two groups (p > 0.05), and the overall agreement (with FICI difference ≤ 0.25 in each isolate) between the two methods was 76.7% (23/30). CONCLUSIONS: The synergy testing results determined by E-test correlated well with microdilution checkerboard. Thus E-test synergy testing has the potential to be used in routine clinical laboratory.

Gridlock from diagnosis to treatment of multidrug-resistant tuberculosis in Tanzania: low accessibility of molecular diagnostic services and lack of healthcare worker empowerment in 28 districts of 5 high burden TB regions with mixed methods evaluation.

BACKGROUND: Multidrug-resistant tuberculosis (MDR-TB) outcomes are adversely impacted by delay in diagnosis and treatment. METHODS: Mixed qualitative and quantitative approaches were utilized to identify healthcare system related barriers to implementation of molecular diagnostics for MDR-TB. Randomly sampled districts from the 5 highest TB burden regions were enrolled during the 4th quarter of 2016. District TB & Leprosy Coordinators (DTLCs), and District AIDS Coordinators (DACs) were interviewed, along with staff from all laboratories within the selected districts where molecular diagnostics tests for MDR-TB were performed. Furthermore, the 2015 registers were audited for all drug-susceptible but retreatment TB cases and TB collaborative practices in HIV clinics, as these patients were in principal targeted for drug susceptibility testing by rapid molecular diagnostics. RESULTS: Twenty-eight TB districts from the 5 regions had 399 patients reviewed for retreatment with a drug-susceptible regimen. Only 160 (40%) had specimens collected for drug-susceptibility testing, and of those specimens only 120 (75%) had results communicated back to the clinic. MDR-TB was diagnosed in 16 (13.3%) of the 120 specimens but only 12 total patients were ultimately referred for treatment. Furthermore, among the HIV/AIDS clinics served in 2015, the median number of clients with TB diagnosis was 92 cases [IQR 32-157] yet only 2 people living with HIV were diagnosed with MDR-TB throughout the surveyed districts. Furthermore, the districts generated 53 front-line healthcare workers for interviews. DTLCs with intermediate or no knowledge on the clinical application of XpertMTB/RIF were 3 (11%), and 10 (39%), and DACs with intermediate or no knowledge were 0 (0%) and 2 (8%) respectively (p = 0.02). Additionally, 11 (100%) of the laboratories surveyed had only the 4-module XpertMTB/RIF equipment. The median time that XpertMTB/RIF was not functional in the 12 months prior to the investigation was 2 months (IQR 1-4). CONCLUSIONS: Underutilization of molecular diagnostics in high-risk groups was a function of a lack of front-line healthcare workforce empowerment and training, and a lack of equipment access, which likely contributed to the observed delay in MDR-TB diagnosis in Tanzania.

Emerging clinical role of pivmecillinam in the treatment of urinary tract infections caused by Extended Spectrum ßeta-lactamase (ESBL) producing Enterobacteriaceae.

BACKGROUND: Extended Spectrum ßeta-lactamase (ESBL)-producing Enterobacteriaceae causing urinary tract infections (UTIs) appear resistant to many common oral agents. There is a growing need to discover new antibiotics to combat with emerging antibiotic resistance problem. Until the discovery of new antimicrobials, we can bring back forgotten antibiotics to our clinical formulary. Pivmecillinam (prodrug of mecillinam), an oral antimicrobial agent is effective against ESBL producing organisms. We analysed the sensitivity rates of ESBL-producing Enterobacteriaceae from urine samples to mecillinam and to document if pivmecillinam is a suitable alternative option in the treatment of UTI. MATERIALS/METHODS: This retrospective study was conducted from September 2015 to September 2017. Data were collected from the pathology information system. Antimicrobial sensitivity testing on ESBL-producing Enterobacteriaceae isolates was carried out by disc diffusion method in accordance with The European Committee on Antimicrobial Susceptibility Testing. RESULTS: A total of 986 ESBL-producing Enterobacteriaceae were tested for mecillinam during the study period. Of 986 organisms, Escherichia coli was the most common organism (889); followed by Klebsiella species (71) and others Enterobacteriaceae (26). Mecillinam sensitivity was found in 96% Escherichia coli (855/889 isolates), 83% Klebsiella species (59/71 isolates) and 88% other Enterobacteriaceae (23/26 isolates). Overall 95% (935/986 isolates) of ESBL-producing urinary isolates were sensitive to mecillinam. CONCLUSIONS: Pivmecillinam appears to be suitable option to treat ESBL-producing Enterobacteriaceae causing uncomplicated UTI. Our results showed low resistance rate to mecillinam. We recommend the use of pivmecillinam in uncomplicated UTIs because of ESBL-producing Enterobacteriaceae. More studies on in vitro activity of mecillinam against ESBL producing organism and its use and clinical outcome should be tried in future.

Measurement uncertainty for the potency estimation by rapid microbiological methods (RMMs) with correlated data.

Recently, rapid microbiological methods (RMM) have often been used to determinate the potency of antibiotic drugs. Since all the standard and sample preparations are assayed into the same analytical conditions, it is expected that the correlations among the inhibitions zone sizes are not negligible. However, the procedures adopted in uncertainty estimations do not consider the correlation of data. The aim of this work was to study the impact of the correlation of data in the measurement uncertainty and, consequently, in the risk of false conformity decisions. RMM for the determination of the potency of cephalosporin antibiotics in pharmaceutical products were performed using an agar diffusion method. The shared analytical effects on inhibition resulted in correlation of data, which significantly decreased the combined measurement uncertainties, and therefore, the risk of false conformity decisions. Due to the lognormal distribution of potency values, measurement uncertainties were reported as a multiplicative uncertainty factor (UF). A MS-Excel spreadsheet is provided as supplementary material and may be used to estimate the measurement uncertainty and the risk of false conformity decisions for results obtained from RMM.

Susceptibility patterns of uropathogens identified in hospitalized children.

BACKGROUND: Urinary tract infection (UTI) is the most common serious bacterial infection in childhood. The aim of the present study was therefore to identify the organisms responsible for community-acquired febrile UTI in children, to investigate their susceptibility to commonly used antibiotics, and to identify possible risk factors for antibiotic resistance. METHODS: A total of 284 children (male, 38%; female, 62%), who were hospitalized due to a community-acquired UTI over a 5 year period in a general district hospital of southern Greece, were enrolled in the study. RESULTS: Escherichia coli was the leading uropathogen followed by Klebsiella spp. (9.15%) and Proteus spp. (5.28%). E. coli isolates were most commonly resistant to ampicillin (41.8%), followed by piperacillin (40.3%), amoxicillin-clavulanic acid (28.6%) and trimethoprim-sulfamethoxazole (17.8%), while 27 strains (12.6%) were multi-drug resistant (MDR). Of the E. coli strains, 4.21% were producing extended-spectrum beta-lactamases. Parenteral second- and third-generation cephalosporins, the most commonly used antibiotic agents (81.3%) in the present cohort, remained highly active against E. coli and other urinary isolates, given that >95% of E. coli strains were susceptible to cefuroxime and cefotaxime. Vesicoureteral reflux was a significant risk factor for MDR (P = 0.04). CONCLUSION: Contrary to current local practice, amoxicillin/clavulanic acid may not be the best option for the empirical treatment of community-acquired UTI in southern Greece.

Effects of Antibiotic Timing on Culture Results and Clinical Outcomes in Pediatric Musculoskeletal Infection.

INTRODUCTION: Musculoskeletal infection (MSI) is a common cause of morbidity and hospital resource utilization in the pediatric population. Many physicians prefer to withhold antibiotics until tissue cultures can be taken in an effort to improve culture yields. However, there is little evidence that this practice improves culture results or outcomes in pediatric MSI. Therefore, investigating the effects of antibiotic timing may lead to improved clinical practice guidelines for treating children with MSI. METHODS: An IRB-approved retrospective review was conducted that identified 113 patients aged 0 to 18 who presented to the pediatric emergency room at a tertiary care children's hospital with MSI from 2008 to 2013. Demographic data, culture results, severity markers, and intervention timing were obtained from the medical record. Logistic regression and Cox survival analysis were performed to determine the relationship of antibiotic timing with culture sensitivity and time to discharge. RESULTS: No difference was seen in culture sensitivity antibiotic administration in either the local (55% culture before antibiotics vs. 89% after antibiotics) or disseminated group (76% before vs. 79% after), which persisted when further accounting for disease severity with C-reactive protein. However, later administration of antibiotics in the local infection group correlated with a decreased likelihood of discharge (3.91 d when cultured before antibiotics vs. 2.93 d when cultured after antibiotics; hazard ratio, 0.53; P<0.05). In patients with disseminated infection, antibiotic administration was not shown to correlate with any difference in time to discharge (hazard ratio, 1.08). CONCLUSIONS: The authors were surprised to find that tissue culture sensitivities were not decreased by antibiotic administration in either local or disseminated MSI, suggesting that antibiotic administration should not be delayed to obtain tissue cultures. The correlation of earlier antibiotic administration with shorter length of stay in children with local MSI led the authors to conclude that antibiotics should be initiated as quickly as possible. Further study is necessary to confirm these findings and establish clinical practice guidelines. LEVEL OF EVIDENCE: Level III-retrospective cohort.

Evaluating Antibiotic Sensitivity Patterns of Pseudomonas in Relation to Specimen Type in Jordanian Hospital.

OBJECTIVE: To evaluate the sensitivity patterns of different antibiotics of pseudomonas in relation to specimen types. METHODS: The quantitative retrospective study was conducted at Princess Iman Research and Laboratory Sciences Centre of Royal Medical Services, Amman, Jordan. The specimens of USS, urine, cerebral spinal fluid, and blood were collected from patients, who visited the hospital from January to September 2015. Drugs analysed included ampicillin, ceftazidime, ciprofloxacin, cefotaxime, cefoxitin, nitrofurantoin and gentamicin. RESULTS: There were 358 samples collected. Ampicillin was found effective (p=0.002). There was a weaker correlation between amikacin and amoxicillin/clavulanic acid (r=-0.001). Similarly, nitrofurantoin was also effective (p=0.001), and the association between amikacin and ceftazidime was positive (r=0.998). CONCLUSIONS: The selected antibiotics were only examined, concerning the sensitivity patterns as data collected from the patients was insufficient for other drugs.

Are In Vitro Susceptibilities to Azole Antifungals Predictive of Clinical Outcome in the Treatment of Candidemia?

The purpose of this review is to critically analyze published data evaluating the impact of azole pharmacokinetic and pharmacodynamic parameters, MICs, and Candida species on clinical outcomes in patients with candidemia. Clinical breakpoints (CBPs) for fluconazole and voriconazole, which are used to determine susceptibility, have been defined by the Clinical and Laboratory Standards Institute (CLSI) for Candida species. Studies evaluating the relationship between treatment efficacy and in vitro susceptibility, as well as the pharmacodynamic targets, have been conducted in patients treated with fluconazole for candidemia; however, for species other than Candida albicans and Candida glabrata, and for other forms of invasive candidiasis, data remain limited and randomized trials are not available. Limited data evaluating these relationships with voriconazole are available. While pharmacodynamic targets for posaconazole and isavuconazole have been proposed based upon studies conducted in murine models, CBPs have not been established by CLSI. Fluconazole remains an important antifungal agent for the treatment of candidemia, and data supporting its use based on in vitro susceptibility are growing, particularly for C. albicans and C. glabrata Further investigation is needed to establish the roles of voriconazole, posaconazole, and isavuconazole in the treatment of candidemia and for all agents in the treatment of other forms of invasive candidiasis.

Urinary tract infections following radical cystectomy and urinary diversion: a review of 1133 patients.

OBJECTIVE: To investigate the incidence and microbiology of urinary tract infection (UTI) within 90 days following radical cystectomy (RC) and urinary diversion. METHODS: We reviewed 1133 patients who underwent RC for bladder cancer at our institution between 2003 and 2013; 815 patients (72%) underwent orthotopic diversion, 274 (24%) ileal conduit, and 44 (4%) continent cutaneous diversion. 90-day postoperative UTI incidence, culture results, antibiotic sensitivity/resistance and treatment were recorded through retrospective review. Fisher's exact test, Kruskal-Wallis test, and multivariable analysis were performed. RESULTS: A total of 151 urinary tract infections were recorded in 123 patients (11%) during the first 90 days postoperatively. 21/123 (17%) had multiple infections and 25 (20%) had urosepsis in this time span. Gram-negative rods were the most common etiology (54% of positive cultures). 52% of UTI episodes led to readmission. There was no significant difference in UTI rate, etiologic microbiology (Gram-negative rods, Gram-positive cocci, fungi), or antibiotic sensitivity and resistance patterns between diversion groups. Resistance to quinolones was evident in 87.5% of Gram-positive and 35% of Gram-negative bacteria. In multivariable analysis, Charlson Comorbidity Index > 2 was associated with higher 90-day UTI rate (OR = 1.8, 95% CI 1.1-2.9, p = 0.05) and Candida UTI (OR 5.6, 95% CI 1.6-26.5, p = 0.04). CONCLUSIONS: UTI is a common complication and cause of readmission following radical cystectomy and urinary diversion. These infections are commonly caused by Gram-negative rods. High comorbidity index is an independent risk factor for postoperative UTI, but diversion type is not.

Robust fit of Bayesian mixed effects regression models with application to colony forming unit count in tuberculosis research.

Early bactericidal activity of tuberculosis drugs is conventionally assessed using statistical regression modeling of colony forming unit (CFU) counts over time. Typically, most CFU counts deviate little from the regression curve, but gross outliers due to erroneous sputum sampling are occasionally present and can markedly influence estimates of the rate of change in CFU count, which is the parameter of interest. A recently introduced Bayesian nonlinear mixed effects regression model was adapted to offer a robust approach that accommodates both outliers and potential skewness in the data. At its most general, the proposed regression model fits the skew Student t distribution to residuals and random coefficients. Deviance information criterion statistics and compound Laplace-Metropolis marginal likelihoods were used to discriminate between alternative Bayesian nonlinear mixed effects regression models. We present a relatively easy method to calculate the marginal likelihoods required to determine compound Laplace-Metropolis marginal likelihoods, by adapting methods available in currently available statistical software. The robust methodology proposed in this paper was applied to data from 6 clinical trials. The results provide strong evidence that the distribution of CFU count is often heavy tailed and negatively skewed (suggesting the presence of outliers). Therefore, we recommend that robust regression models, such as those proposed here, should be fitted to CFU count.