Penicillin

About: Penicillin is a research topic. Over the lifetime, 17916 publications have been published within this topic receiving 368480 citations. The topic is also known as: penicillin antibiotic & PCN.

Impact of pneumococcal conjugate vaccine and of reduction of antibiotic use on nasopharyngeal carriage of nonsusceptible pneumococci in children with acute otitis media.

Abstract: BACKGROUND: Penicillin resistance among pneumococci has increased in the past 15 years. The implementation of widespread vaccination with the heptavalent pneumococcal conjugate vaccine (PCV7) and the reduction of inappropriate antibiotic use could help reduce antibiotic resistance. METHODS: Between September 2001 and June 2004, 89 pediatricians distributed throughout France took part in this prospective study. We obtained 1906 nasopharyngeal swabs for culture from children aged 6 to 24 months with acute otitis media (AOM). At the same time as PCV7 was introduced into the routine immunization schedule, a plan to promote judicious antibiotic use was established. We recorded the frequency of antibiotic use, as well as the dates of immunization with PCV7. RESULTS: The proportion of PCV7-vaccinated children (> or =1 dose) increased from 8.2% (year 1) to 61.4% (year 3). The proportion of children who received antibiotics within 3 months before enrollment decreased from 51.8% in year 1 to 40.9% in year 3 (P < 0.001). Overall pneumococcal carriage and carriage of PCV7 serotypes decreased during the 3-year period by 16% (P < 0.001) and 35% (P < 0.001), respectively. Rates of highly penicillin resistant strains (PRP) decreased yearly: 15.4%, 10.6%, 6.7% (P < 0.001), respectively. Risks for PRP carriage were 4.2% for immunized children who had not received antibiotics, 8.6% for those vaccinated who also had received antibiotics, 10.3% for unimmunized children who had not received antibiotics, and 16.2% for unimmunized children who had received antibiotics (P < 0.001). CONCLUSION: Implementation of PCV7, combined with a reduction in antibiotic use, in a country with a high prevalence of antibiotic-resistant pneumococci appears to have a strong impact on the carriage of penicillin nonsusceptible pneumococci in children with AOM.

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

Antimicrobial Therapy of Experimental Endocarditis Caused by Staphylococcus aureus

Abstract: The rate at which various antimicrobial agents eradicated Staphylococcus aureus from cardiac vegetations in a rabbit model of endocarditis was studied. The rate at which various drugs and combinations killed high titers of bacteria in broth correlated with the relative effectiveness of the agents in vivo. Gentamicin plus penicillin proved to be synergistic in vitro and more effective in eradicating bacteria from cardiac vegetations in vivo than was penicillin alone. Vancomycin killed bacteria at a rate similar to that for the combination of penicillin and gentamicin, and the rate for cefazolin was similar to that for penicillin alone. Clindamycin was less effective in vivo and in vitro than penicillin. Therapy with rifampin led to the emergence of resistant organisms, and, when penicillin, this drug was less effective in vitro and in vivo than was penicillin alone. This model appears to offer an effective method for evaluation of antimicrobial treatment of staphylococcal endocarditis.

Multiple Antibiotic Resistance due to a Single Mutation in Neisseria gonorrhoeae

Abstract: A positive correlation (r > +.47, P 1 .01) was found between sensitivities of 147 random clinical isolates of Neisseria gonorrhoeae to all possible pairs of the drugs penicillin, tetracycline, erythromycin, chloramphenicol, acridine orange, and ethidium bromide. High-level resistance to streptomycin was also positively correlated with increased resistance to some of these drugs. This suggested that multiply-resistant strains are not exclusively the result of selection of independent mutants for resistance to each drug and that there may be a common mechanism for resistance to some or all of these drugs. This hypothesis was supported by the demonstration that low-level resistance to a large group of drugs (penicillin, tetracycline, erythromycin, chloramphenicol, rifampin, ethidium bromide, and acridine orange) could be lost as well as restored by a single mutational event in vitro. Resistance of Neisseria gonorrhoeae to antibiotics has gradually become an important practical problem during the last decade [1-6], but there has been almost no scientific inquiry into the genetic and biochemical mechanisms of resistance. Several features of the clinical epidemiology of resistance of the gonococcus to antibiotics aroused our curiosity and prompted these studies. Numerous authors have noted strong positive correlations between sensitivities of individual