Showing papers on "Penicillin published in 2011"

Fleming's penicillin producing strain is not Penicillium chrysogenum but P. rubens.

Abstract: Penicillium chrysogenum is a commonly occurring mould in indoor environments and foods, and has gained much attention for its use in the production of the antibiotic penicillin. Phylogenetic analysis of the most important penicillin producing P. chrysogenum isolates revealed the presence of two highly supported clades, and we show here that these two clades represent two species, P. chrysogenum and P. rubens. These species are phenotypically similar, but extrolite analysis shows that P. chrysogenum produces secalonic acid D and F and/or a metabolite related to lumpidin, while P. rubens does not produce these metabolites. Fleming’s original penicillin producing strain and the full genome sequenced strain of P. chrysogenum are re-identified as P. rubens. Furthermore, the well-known claim that Alexander Fleming misidentified the original penicillin producing strain as P. rubrum is discussed.

Wax moth larva (Galleria mellonella): an in vivo model for assessing the efficacy of antistaphylococcal agents

Abstract: Objectives: To investigate whether the wax moth larva, Galleria mellonella, is a suitable host for assessing the in vivo efficacy of antistaphylococcal agents against Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) infections. Methods: Wax moth larvae were infected with increasing doses of S. aureus to investigate the effect of inoculum size on larval survival. In addition, infected wax moth larvae were treated with daptomycin, penicillin or vancomycin to examine whether these agents were effective against S. aureus and MRSA infections in vivo. Results: Increasing inoculum doses of live S. aureus cells resulted in greater larval mortality, but heat-killed bacteria and cell-free culture filtrates had no detrimental effects on survival. Larval mortality rate also depended on the post-inoculation incubation temperature. After larvae were infected with S. aureus, larval survival was enhanced by administering the antistaphylococcal antibiotics daptomycin or vancomycin. Larval survival increased with increasing doses of the antibiotics. Moreover, penicillin improved survival of larvae infected with a penicillin-susceptible methicillin-susceptible S. aureus (MSSA) strain, but it was ineffective at similar doses in larvae infected with MRSA (penicillin resistant). Daptomycin and vancomycin were also effective when administered to the larvae prior to infection with bacteria. Conclusions: This is the first report to demonstrate that antibiotics are effective in the wax moth larva model for the treatment of infections caused by Gram-positive bacteria. The new wax moth larva model is a useful preliminary model for assessing the in vivo efficacy of candidate antistaphylococcal agents before proceeding to mammalian studies, which may reduce animal experimentation and expense.

Outpatient Antibiotic Prescribing and Nonsusceptible Streptococcus pneumoniae in the United States, 1996–2003

Abstract: Background. Streptococcus pneumoniae infections have become increasingly complicated and costly to treat with the spread of antibiotic resistance. We evaluated the relationship between antibiotic prescribing and nonsusceptibility among invasive pneumococcal disease (IPD) isolates. Methods. Outpatient antibiotic prescription data for penicillins, cephalosporins, macrolides, and trimethoprim-sulfamethoxazole were abstracted from the IMS Health Xponent database to calculate the annual number of prescriptions per capita. We analyzed IPD data from 7 of the Centers for Disease Control and Prevention’s Active Bacterial Core surveillance sites (population, 18.6 million) for which data were available for the entire time period under study (1996–2003). Logistic regression models were used to assess whether sites with high antibiotic prescribing rates had a high proportion of nonsusceptible and serotype 19A IPD. Results. Yearly prescribing rates during the period 1996–2003 for children ,5 years of age decreased by 37%, from 4.23 to 2.68 prescriptions per capita per year (P , .001), and those for persons $5 years of age decreased by 42%, from 0.98 to 0.57 prescriptions per capita per year (P , .001); increases in azithromycin prescribing were noted for both groups. Sites with high rates of antibiotic prescribing had a higher proportion of IPD nonsusceptibility than did low-prescribing sites (P 5 .003 for penicillin, P , .001 for every other antibiotic class). Cephalosporin and macrolide prescribing were associated with penicillin and multidrug nonsusceptibility and serotype 19A IPD (P , .001). Conclusions. In sites where antibiotic prescribing is high, the proportion of nonsusceptible IPD is also high, suggesting that local prescribing practices contribute to local resistance patterns. Cephalosporins and macrolides seem to be selecting for penicillin- and multidrug-resistant pneumococci, as well as serotype 19A IPD. Antibiotic use is a major factor contributing to the spread of antibiotic resistance; strategies to reduce antibiotic resistance should continue to include judicious use of antibiotics. Disease caused by Streptococcus pneumoniae, the leading cause of severe bacterial respiratory illness and

European Surveillance of Antimicrobial Consumption (ESAC): outpatient penicillin use in Europe (1997–2009)

Abstract: Background Data on 13 years (1997-2009) of outpatient penicillin use were collected from 33 European countries within the European Surveillance of Antimicrobial Consumption (ESAC) project and analysed in detail. Methods For the period 1997-2009, data on outpatient use of systemic penicillins aggregated at the level of the active substance were collected using the Anatomical Therapeutic Chemical (ATC)/defined daily dose (DDD) method (WHO, version 2011) and expressed in DDD per 1000 inhabitants per day (DID). For detailed analysis of trends over time, seasonal variation and composition of outpatient penicillin use in 33 European countries, we distinguished between narrow-spectrum penicillins (NSP), broad-spectrum penicillins (BSP), penicillinase-resistant penicillins (PRP) and combinations with β-lactamase inhibitors (COP). Results Total outpatient penicillin (ATC group J01C) use in 2009 varied by a factor of 3.8 between the countries with the highest (16.08 DID in France) and lowest (4.23 DID in the Russian Federation) use. COP represented 45.8%, BSP 40.7%, NSP 10.8% and PRP 2.6% of total European outpatient penicillin use. Total outpatient penicillin use significantly increased over time by 1.53 (SD 0.71) DID between 1997 and 2009. COP (mainly co-amoxiclav) increased by 2.17 (SD 0.40) DID, which was the result of its absolute increase as well as the observed shift from NSP and BSP towards COP. This increase exceeded 10% in 20 countries, where it coincided with a similar decrease in either BSP (15 countries) or NSP (5 countries). Conclusions Penicillins represented the most widely used antibiotic subgroup in all 33 participating countries, albeit with considerable variation in their use patterns. For Europe, a continuous increase in overall penicillin use and of COP use was observed during the period 1997-2009.

Penicillin: the medicine with the greatest impact on therapeutic outcomes.

Abstract: The principal point of this paper is that the discovery of penicillin and the development of the supporting technologies in microbiology and chemical engineering leading to its commercial scale production represent it as the medicine with the greatest impact on therapeutic outcomes. Our nomination of penicillin for the top therapeutic molecule rests on two lines of evidence concerning the impact of this event: (1) the magnitude of the therapeutic outcomes resulting from the clinical application of penicillin and the subsequent widespread use of antibiotics and (2) the technologies developed for production of penicillin, including both microbial strain selection and improvement plus chemical engineering methods responsible for successful submerged fermentation production. These became the basis for production of all subsequent antibiotics in use today. These same technologies became the model for the development and production of new types of bioproducts (i.e., anticancer agents, monoclonal antibodies, and industrial enzymes). The clinical impact of penicillin was large and immediate. By ushering in the widespread clinical use of antibiotics, penicillin was responsible for enabling the control of many infectious diseases that had previously burdened mankind, with subsequent impact on global population demographics. Moreover, the large cumulative public effect of the many new antibiotics and new bioproducts that were developed and commercialized on the basis of the science and technology after penicillin demonstrates that penicillin had the greatest therapeutic impact event of all times.

Amoxicillin: a broad spectrum antibiotic

Abstract: Amoxicillin though originally introduced in the early 1970’s for oral use in U.K., has found a gradually regular place as broad spectrum antibacterial to treat the infections of various diseases. Amoxicillin has been found to be more effective against gram positive than gram negative micro‐ organisms and demonstrated greater efficacy to penicillin and penicillin V. Moreover, it has been found comparable to other antibiotics, e.g. ampicillin, azithromycin, clarithromycin, cefuroxime and doxycycline in treatment of various infections/ diseases. In the past decade, amoxicillin has been reported to be useful in the management of many indications and is used to treat infections of the middle ear (otitis media) , tonsils (tonsillitis & tonsillopharyngitis), throat, larynx (laryngitis) , pharynx (pharyngitis), bronchi (bronchitis), lungs (pneumonia), urinary tract (UTI), skin and to treat gonorrhoea. Recent studies suggested that it can be used as prophylaxis against bacterial endocarditis, in patients with prosthetic joint replacements and in dentistry. The renewed interest of the molecule has prompted a review of the salient facets of the drug.

Antimicrobial susceptibility of Staphylococcus aureus and Staphylococcus pseudintermedius isolated from various animals

Abstract: This study characterized the antimicrobial susceptibility of 221 Staphylococcus aureus isolated from various species, and 60 canine Staphylococcus pseudintermedius isolated from 1986 through 2000 at the Western College of Veterinary Medicine (WCVM). Resistance of S. aureus was most common to penicillin (31%) and tetracycline (14%); resistance of S. pseudintermedius to penicillin was present in 8% and to tetracycline in 34% of isolates. Resistance to trimethoprim/sulfamethoxazole was only seen among S. pseudintermedius, and there was no resistance to amoxicillin/clavulanate, ampicillin/sulbactam, cephalothin, amikacin, gentamicin, enrofloxacin, chloramphenicol, or rifampin among any isolate. Inducible clindamycin resistance was found in both S. aureus and S. pseudintermedius, highlighting the need for careful interpretation of culture and susceptibility test results. There were significant differences in the minimum inhibitory concentrations of penicillin, ciprofloxacin, enrofloxacin, clindamycin, erythromycin, chloramphenicol, and tetracycline between avian, bovine, equine, and porcine isolates.

Scale-down of penicillin production in Penicillium chrysogenum

Abstract: In large-scale production reactors the combination of high broth viscosity and large broth volume leads to insufficient liquid-phase mixing, resulting in gradients in, for example, the concentrations of substrate and oxygen. This often leads to differences in productivity of the full-scale process compared with laboratory scale. In this scale-down study of penicillin production, the influence of substrate gradients on process performance and cell physiology was investigated by imposing an intermittent feeding regime on a laboratory-scale culture of a high yielding strain of Penicillium chrysogenum. It was found that penicillin production was reduced by a factor of two in the intermittently fed cultures relative to constant feed cultivations fed with the same amount of glucose per hour, while the biomass yield was the same. Measurement of the levels of the intermediates of the penicillin biosynthesis pathway, along with the enzyme levels, suggested that the reduction of the flux through the penicillin pathway is mainly the result of a lower influx into the pathway, possibly due to inhibitory levels of adenosine monophosphate and pyrophosphate and lower activating levels of adenosine triphosphate during the zero-substrate phase of each cycle of intermittent feeding.

Novel mutations in a patient isolate of Streptococcus agalactiae with reduced penicillin susceptibility emerging after long term oral suppressive therapy

Abstract: Penicillin nonsusceptibility has been demonstrated in group B streptococci (GBS), but there is limited information regarding mechanisms of resistance. We report a case of GBS with reduced susceptibility to penicillin emerging after long-term suppressive oral penicillin therapy for a prosthetic joint infection. Molecular characterization of the isolate before and after long-term penicillin therapy revealed 5 mutations in the ligand-binding regions of PBP1a, -2a, and -2x not previously reported in GBS.

Antibiotic sensitivity pattern of Staphylococcus aureus from clinical isolates in a tertiary health institution in Kano, Northwestern Nigeria

Abstract: BACKGROUND: The importance of Staphylococcus aureus as a persistent nosocomial and community acquired pathogen has become a global health concern It has a remarkable capability of evolving different mechanisms of resistance to most antimicrobial agents The aim of the present study is to establish the incidence of S aureus in clinical specimens and its antibiotic sensitivity pattern to various antibiotics in this locality METHODS: One hundred and fifty consecutive isolates of S aureus obtained from various clinical specimens between January and December 2009 sent to the Medical Microbiology Laboratory Department of Aminu Kano Teaching Hospital (AKTH) were confirmed by standard bacteriological procedures Antibiotic sensitivity pattern was carried out by disc diffusion method RESULTS: The age group with the highest number of isolates was (0-10)yrs while wound infection had the highest frequency of S aureus isolates (307%) in the study Males (620%) were more infected than females (380%) The sensitivity pattern of S aureus to the following antibiotics; Gentamicin, Amoxycillin/clavulanate, Streptomycin, Cloxacillin, Erythromycin, Chloramphenicol, Cotrimoxazole, Tetracycline, Penicillin, Ciprofloxacin, Ofloxacin, Levofloxacin, Ceftriaxone, Amoxycillin and vancomycin were 924%, 630%, 442%, 358%, 524%, 619%, 155%, 312%, 71%, 789%, 766%, 100%, 714%, 307% and 100% respectively Methicillin resistant isolates were sensitive to Levofloxacin 937% and Ofloxacin 687% CONCLUSION: The results of the present study show that the fluoroquinolones are effective in the management of Staphylococcus aureus infections including methicillin resistant strains in this environment

Antimicrobial Susceptibility of Staphylococcus aureus and Characterization of Methicillin-Resistant Staphylococcus aureus Isolated from Bovine Mastitis in Korea

Abstract: A total of 402 Staphylococcus aureus isolates from bovine mastitis milk collected during 2003-2009 in Korea were tested for susceptibility to 20 antimicrobial agents. All S. aureus isolates were susceptible to 11 of 20 antimicrobials tested; no resistance was observed against pirlimycin, telithromycin, novobiocin, penicillin/novobiocin, quinupristin/dalfopristin, clindamycin, rifampin, ciprofloxacin, trimethprim/sulfamethoxazol, vancomycin, and linezolid. Over 66% of the S. aureus isolates were resistant to penicillin. Resistance was also seen for gentamicin (11.9%), erythromycin (7.7%), methicillin (oxacillin and cefoxitin, 6.2%), and tetracycline (4.2%). No noticeable change was observed in penicillin, gentamicin, and erythromycin resistance over the 7-year period. Tetracycline resistance appeared to decrease consistently, whereas methicillin resistance was observed from 2005. About 2.7% (11/402) were resistant to three or more antimicrobials. Genotyping of the 17 methicillin-resistant S. aureus (MRSA) isolated from each cow revealed two staphylococcal cassette chromosome mec (SCCmec) types (IV and IVa), three spa types (t286, t324, and untypable), and two sequence types (ST1 and ST72). Eleven of 17 (64.7%) MRSA strains belonged to SCCmec IVa-t324-ST72. The rest of strains belonged to SCCmec IVa-t286-ST1 (n = 3) and SCCmec IV-untypable-ST72 (n = 3). None of the MRSA carried the Panton-Valentine leukocidin gene. These characteristics are the same as those found in community-acquired (CA) MRSA strains prevalent in humans in Korea. Three pulsed-field gel electrophoresis types (A-C) were observed among the 17 MRSA strains examined, and 14 strains belonged to the same pulsed-field gel electrophoresis pattern regardless of their geographical origin and year of isolation. The results of this study provide evidence of CA-MRSA infection in dairy cattle for the first time in Korea.

Penicillin skin testing in the evaluation and management of penicillin allergy.

Abstract: Objective To review the role of penicillin skin testing in the evaluation and management of penicillin allergy mediated by IgE. Data Sources PubMed and OVID search of English-language articles regarding penicillin allergy, penicillin allergy testing, and management of penicillin allergy. Study Selection Articles pertinent to the subject matter were selected and reviewed. Results The major determinant (benzylpenicillin polylysine) detects the greatest number of penicillin allergic patients during skin testing, and the minor determinants of penicillin increase the sensitivity of penicillin skin testing. Penicillin skin testing to the major and minor determinants was found to have a negative predictive value of 97% to 99%. The incidence of systemic adverse reaction to penicillin skin testing is less than 1%. Conclusion A detailed history of the prior reaction to penicillin is an integral part of the evaluation, but it is not accurate in predicting a positive penicillin skin test result. A patient with a negative penicillin skin test result to the major and minor determinants is at a low risk of an immediate-type hypersensitivity reaction to penicillin. Patients with a positive skin test result should undergo desensitization to penicillin or an alternative antibiotic should be considered.

Isolation and Identification of Vancomycin Resistant Staphylococcus aureus from Post Operative Pus Sample

Abstract: Staphylococcus aureus is most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Recently, S. aureus have evolved resistance to both synthetic and traditional antibiotics. This study was carried out to isolate pathogenic S. aureus from post-operative pus sample, and VRSA was identified by evaluation of resistance patterns using conventional antibiotics. Thirty post operative pus samples were collected from nearby Hospital and species identification was confirmed by Gram staining, standard biochemical tests and PCR amplification of the nuc gene. Antibiotic susceptibility tests were carried out by MIC, MBC, DAD test and BHI vancomycin screening agar. VRSA were confirmed by PCR amplification of the vanA and vanB genes. From this study, it was observed that isolated S. aureus strains are pathogenic; 30% of strains were resistant to penicillin G, ampicillin and erythromycin; 26.67% strains were resistant to cephotaxime, gentamycin, streptomycin, tetracycline, chloramphenicol, norfloxacin, methicillin and vancomycin.

Antibiotic susceptibility of coagulase-negative staphylococci (CoNS): emergence of teicoplanin-non-susceptible CoNS strains with inducible resistance to vancomycin

Abstract: Coagulase-negative staphylococci (CoNS) have become increasingly recognized as important agents of nosocomial infection. One of the characteristics of CoNS is their resistance to multiple antimicrobial agents commonly used for the treatment of staphylococcal infections. CoNS strains (n = 745) isolated from a university teaching hospital in China between 2004 and 2009 were tested for antibiotic resistance. The antibiotics were placed into three categories based on resistance levels of the CoNS strains to these antibiotics: high resistance (resistance rate >70 %), including penicillin G, oxacillin and erythromycin; medium resistance (resistance rate between 30 and 70 %), including tetracycline, clindamycin, ciprofloxacin, trimethoprim/sulfamethoxazole and chloramphenicol; and low resistance (resistance rate <30 %), including rifampicin, ceftizoxime and gentamicin. We also found that the prevalence of strains non-susceptible to teicoplanin increased from 4.5 to 6.7 % between 2008 and 2009. A one-step vancomycin agar selection experiment and subsequent population analysis revealed potentially vancomycin-resistant subpopulations that have been selected from the teicoplanin-non-susceptible strains. Vigilant surveillance of nosocomial isolates of CoNS is needed to determine their resistance to glycopeptides.

Novel bioactive metabolites producing endophytic fungus Colletotrichum gloeosporioides against multidrug‐resistant Staphylococcus aureus

Abstract: The emergence of antibiotic-resistant bacteria such as Staphylococcus aureus calls for inventive research and development strategies. Inhibition of this bacterial pathogenesis may be a promising therapeutic approach. The screening of antimicrobial compounds from endophytes is a promising way to meet the increasing threat of drug-resistant strains of human and plant pathogens. In the present study, a novel endophytic fungus, Colletotrichum gloeosporioides , was isolated from the medicinal plant Vitex negundo L. Extracts of C. gloeosporioides were obtained using hexane, ethyl acetate and methanol solvents. The fungal extracts exhibited an effective antimicrobial activity against bacterial and fungal strains. The extracts were also analysed for antibacterial activity against methicillin-, penicillin- and vancomycin-resistant S. aureus strains (1–10). The methanol extract showed an effective antibacterial activity against S. aureus strain 9, with a minimal inhibitory concentration of 31.25 µg mL−1. The synergistic action of endophytic fungal extract with antibiotics such as methicillin, penicillin and vancomycin was observed against S. aureus strain 6. The fractional inhibitory concentration index of methanol extract with methicillin, penicillin and vancomycin was 1.0, 0.5 and 0.375, respectively. These results clearly indicate that the metabolite of endophytic fungus C. gloeosporioides is a potential source of new antibiotics.

Decrease in Penicillin Susceptibility Due to Heat Shock Protein ClpL in Streptococcus pneumoniae

Abstract: Antibiotic resistance and tolerance are increasing threats to global health as antibiotic-resistant bacteria can cause severe morbidity and mortality and can increase treatment cost 10-fold Although several genes contributing to antibiotic tolerance among pneumococci have been identified, we report here that ClpL, a major heat shock protein, could modulate cell wall biosynthetic enzymes and lead to decreased penicillin susceptibility On capsular type 1, 2, and 19 genetic backgrounds, mutants lacking ClpL were more susceptible to penicillin and had thinner cell walls than the parental strains, whereas a ClpL-overexpressing strain showed a higher resistance to penicillin and a thicker cell wall Although exposure of Streptococcus pneumoniae D39 to penicillin inhibited expression of the major cell wall synthesis gene pbp2x, heat shock induced a ClpL-dependent increase in the mRNA levels and protein synthesized by pbp2x Inducible ClpL expression correlated with PBP2x expression and penicillin susceptibility Fractionation and electron micrograph data revealed that ClpL induced by heat shock is localized at the cell wall, and the ΔclpL showed significantly reduced net translocation of PBP2x into the cell wall Moreover, coimmunoprecipitation with either ClpL or PBP2x antibody followed by reprobing with ClpL or PBP2x antibody showed an interaction between ClpL and PBP2x after heat stress This interaction was confirmed by His tag pulldown assay with either ClpLHis₆ or PBP2xHis₆ Thus, ClpL stabilized pbp2x expression, interacted with PBP2x, and facilitated translocation of PBP2x, a key protein of cell wall synthesis process, contributing to the decrease of antibiotic susceptibility in S pneumoniae

Resistencia a los antibacterianos en América Latina: consecuencias para la infectología

Abstract: Antibacterial drug resistance is a particularly significant issue in Latin America. This article explores antimicrobial resistance in three classes of clinically important bacteria: gram-positive bacteria, enterobacteria, and nonfermenting gram-negativebacilli. The gram-positive bacteria frequently responsible for infections in humans are for the most part cocci: staphylococci, streptococci (including pneumococci), and enterococci,in both community and hospital settings. This situation is no different in theRegion of the Americas. Among the gram-positive bacteria, the causative agents of bacteremia are most commonly strains of coagulase-negative Staphylococcus, followed by enterococci. This report explores the resistance of these species to different antimicrobial drugs, resistance mechanisms in community and hospital strains, and new drugs for treating infections caused by these bacteria. In Latin America, antimicrobialresistance in Enterococcus strains is still a minor problem compared to the situation in the United States. The strains of the genus Streptococcus isolated from respiratory infections are still sensitive to penicillin. Furthermore, the resistance of enterobacteriais extremely important in the Region, particularly because of the broad dissemination of CTX-M extended-spectrum beta-lactamases (ESBL), some of which originated in Latin America. This article analyzes the resistance of Streptococcus pneumoniae, betahemolytic streptococci, and viridans group streptococci. Among the nonfermentinggram-negative bacilli, while Pseudomonas aeruginosa strains remain the leading cause of bacteremia, infections caused by strains of Acinetobacter spp. have proliferatedextensively in some areas. With regard to antibiotics, several options are available for treating gram-positive bacterial infections...(AU)

Antimicrobial Susceptibility of Clinically Relevant Gram-Positive Anaerobic Cocci Collected over a Three-Year Period in the Netherlands

Abstract: The susceptibility of 14 species of 115 Gram-positive anaerobic cocci (GPAC) was determined for 14 antibiotics. To assure correct identification, strains were genotypically identified by fluorescence in situ hybridization and sequencing. Susceptibility differences (MIC 50 and MIC 90 ) for penicillin G, clindamycin, tigecycline, levofloxacin, amoxicillin-clavulanic acid, cefoxitin, ertapenem, meropenem, metronidazole, and doxycycline were found for the three clinically most relevant GPAC species: Finegoldia magna , Parvimonas micra , and Peptoniphilus harei .

Rheumatic fever recurrence prevention: a nurse-led programme of 28-day penicillin in an area of high endemnicity.

Abstract: Aims: To evaluate safety and effectiveness of 28-day long-acting penicillin to prevent recurrences of acute rheumatic fever (ARF). Methods: Historical cohort study using the regional RF register for Auckland, New Zealand, in a 5–14-year-old population with ARF rates of ∼40–80/100 000. Consented patients were referred to a population-based delivery programme of free benzathine penicillin every 28 days by community nurses with discharge after the longer of 10 years of treatment or aged 21 years. First-episode and recurrent ARF cases classified as definite (Jones criteria 1992) or probable (Jones criteria 1956) were the main outcome measures. Results: Of the 360 cases meeting the case definitions, 20 recurrences occurred in 19 people (median age 21 years). The age at first episode was 2–52 years (mode 11 years), median age 21.3 (8–40). ARF recurred 0–21 years after penicillin was discontinued. Seventy-two per cent of recurrent cases occurred within 5 years, and 12% between 5 years and 10 years. The 4-weekly long-acting penicillin failure rate (n= 1) was 0.07/100 patient years. The programme failure rate (Auckland residents) was 1.4/100 patient years (n= 20). Patient non-adherence accounted for 55% of recurrences. Two recurrences after discharge from prophylaxis as per the New Zealand guidelines occurred 3 years and 13 years later. Conclusions: In this environment, 28-day long-acting penicillin prophylaxis for at least 10 years delivered by community nurses is safe and effective for patients with no or mild cardiac disease by auscultation at discharge off penicillin. Penicillin delivery every 21 days (as suggested by a recent Cochrane review) would add to costs and complexity.

Antimicrobial susceptibility of Listeria monocytogenes food isolates from different cities in Colombia.

Abstract: One hundred eight Listeria monocytogenes food isolates from four cities in Colombia and previously confirmed by multiplex polymerase chain reaction were characterized for antimicrobial susceptibility. Isolates were evaluated against 17 antimicrobials contained in the MICroSTREP plus(®)3 panel (MicroScan system). Susceptibility found for ampicillin, amoxicillin/clavulanic acid, and chloramphenicol was 100%, whereas it was 98% for other antimicrobials such as trimethoprim/sulfamethoxazole, 97% for azithromycin, 92% for vancomycin, 90% for erythromycin, 86% for tetracycline, 84% for penicillin, 70% for ciprofloxacin, 57% for rifampin, 56% for meropenem, and 32% for clindamycin. Natural resistance to cephalosporins was confirmed in all cases, and 16% of isolates were nonsusceptible to penicillin. Using Staphylococcus spp. or Enterococcus spp. breakpoints, 48% of isolates displayed multidrug resistances, and the major resistance phenotypes were against rifampin, clindamycin, ciprofloxacin, azithromycin, and erythromycin. Colombian food isolates displayed high resistance to clindamycin, meropenem, rifampin, and ciprofloxacin (30%-65%), and the primary drugs of choice against listeriosis remain effective for most of isolates (84%).

Antimicrobial resistance in group B streptococcus: the Australian experience

Abstract: Intrapartum chemoprophylaxis for pregnant group B streptococcus (GBS) carriers reduces vertical transmission, with a resultant decrease in neonatal as well as maternal morbidity from invasive GBS infection. Current Australian guidelines recommend penicillin for intrapartum prophylaxis of GBS carriers, with erythromycin or clindamycin for those with a β-lactam allergy. Recent reports globally suggest that resistance to erythromycin and clindamycin may be increasing; hence, a study was undertaken to promote an evidence base for local clinical guidelines. Samples collected for standardized susceptibility testing included 1160 invasive GBS isolates (264 isolates retrospectively from 1982 to 2001 and prospectively from 2002 to 2006, plus 896 prospectively collected colonizing GBS isolates gathered over a 12 month period from 2005 to 2006) from 16 laboratories around Australia. All isolates displaying phenotypic macrolide or lincosamide resistance were subsequently genotyped. No isolates showed reduced susceptibility to penicillin or vancomycin. Of the invasive isolates, 6.4% demonstrated phenotypic erythromycin resistance and 4.2% were clindamycin resistant. Of the erythromycin-resistant isolates, 53% showed cross-resistance to clindamycin. Very similar results were found in colonizing specimens. There was no statistically significant change in macrolide-resistance rates over the two study periods 1982-2001 and 2002-2006. Genotyping for macrolide and lincosamide-resistant isolates was largely consistent with phenotype. These findings suggest that penicillin therapy remains an appropriate first-line antibiotic choice for intrapartum GBS chemoprophylaxis, with erythromycin and/or clindamycin resistance being low in the Australian population. It would, nevertheless, be appropriate for laboratories screening for GBS in obstetric patients to consider macrolide sensitivity testing, particularly for those with β-lactam allergy, to ensure appropriate chemoprophylaxis.

Collaboration between allergists and pharmacists increases β-lactam antibiotic prescriptions in patients with a history of penicillin allergy.

Abstract: Background: Over 90% of patients with a history of penicillin allergy have negative penicillin skin tests. Pharmacists are trained to identify and resolve medication-related problem