Has the licensing of respiratory quinolones for adults and the 7-valent pneumococcal conjugate vaccine (PCV-7) for children had herd effects with respect to antimicrobial non-susceptibility in invasive Streptococcus pneumoniae?

OBJECTIVES: The aim of the study was to analyse the evolution of antibiotic non-susceptibility in Spanish invasive Streptococcus pneumoniae after licensure of respiratory-quinolones for adults and 7-valent pneumococcal conjugate vaccine (PCV-7) for immunization of children. METHODS: All invasive pneumococci received in the Reference Laboratory (January 2000-August 2007; n = 12 957 isolates) were serotyped, and susceptibility to penicillin/erythromycin/levofloxacin was determined. Antibiotic consumption and PCV-7 doses/year were provided by IMS and the manufacturer, respectively. RESULTS: In 2000-07, PCV-7 distribution (doses/1000 inhabitants

Influence of penicillin/amoxicillin non-susceptibility on the activity of third-generation cephalosporins against Streptococcus pneumoniae.

To study the influence of penicillin/amoxicillin non-susceptibility on the activity of third-generation cephalosporins, 430 consecutive penicillin non-susceptible Streptococcus pneumoniae 2007 isolates received in the Spanish Reference Pneumococcal Laboratory were tested. For comparative purposes, 625 penicillin-susceptible 2007 isolates were also tested. Susceptibility was determined by agar dilution using Mueller-Hinton agar supplemented with 5% sheep blood. Penicillin-susceptible strains were susceptible to amoxicillin, cefotaxime and ceftriaxone, 99.8% to cefpodoxime and 99.5% to cefdinir, and were inhibited by 0.12 microg/ml of cefditoren and 4 microg/ml of cefixime. Penicillin-intermediate strains were susceptible to cefotaxime and ceftriaxone, with <50% susceptibility to cefdinir and cefpodoxime. The MIC(50) and MIC(90) values of cefditoren were 0.25 microg/ml and 0.5 microg/ml, respectively, whereas cefixime exhibited only marginal activity (MIC(90)=16 microg/ml). Penicillin-resistant strains were resistant to cefdinir and cefpodoxime, with 74.8% and 94.1% susceptibility to cefotaxime and ceftriaxone, respectively. Cefditoren MIC(50)/MIC(90) (0.5/1 microg/ml) were lower than cefotaxime and ceftriaxone. Among amoxicillin non-susceptible strains, susceptibility to cefdinir and cefpodoxime was <10%, and susceptibility to cefotaxime decreased from 87.9% in the intermediate category to 63.0% in the resistant group. Cefditoren MIC(50)/MIC(90) (0.5/1 microg/ml) were lower than cefotaxime. In conclusion, the activity of cefixime, cefdinir and cefpodoxime was highly affected by penicillin/amoxicillin non-susceptibility, while parenteral third-generation cephalosporins exhibited higher intrinsic activity (MIC(90)=1 microg/ml for penicillin-resistant and 2 microg/ml for amoxicillin-resistant strains). Cefditoren exhibited one-dilution lower MIC(90) values for these strains, even against those of the most troublesome serotypes.

Odontogenic bacteria in periodontal disease and resistance patterns to common antibiotics used as treatment and prophylaxis in odontology in Spain.

Resistance in streptococci or Gram-negative bacteria is associated with antibiotic consumption. Scarce information exists on the antibiotic susceptibility of bacterial isolates from patients with periodontitis in countries with high antibiotic consumption, as this is an area in which microbiological testing is not performed in daily practice. The present study was undertaken to explore the susceptibility of bacterial isolates in periodontitis to antibiotics prescribed in odontology in Spain as treatment for local infections or prophylaxis for distant focal infections. Periodontal samples were prospectively collected in 48 patients classified by pocket depth of <4 mm and >or=4 mm. Species were identified by culture, selecting the five most frequent morphotypes per sample, and polymerase chain reaction (PCR). Susceptibility was determined by E-test. A total of 261 isolates were identified: 72.9% patients had Streptococcus oralis; 70.8% Streptococcus mitis; 60.4% Prevotella buccae; 39.6% Prevotella denticola; 37.5% Fusobacterium nucleatum; 35.4% Prevotella intermedia; 25% Capnocytophaga spp.; 23% Veillonella spp.; 22.9% Prevotella melaninogenica and Streptococcus sanguis; and <20% other species. Streptococcus viridans resistance rates were 0% for amoxicillin, approximately 10% for clindamycin, 9-22% for tetracycline, and for azithromycin ranged from 18.2% for S. sanguis to 47.7% for S. mitis. Prevotella isolates were susceptible to amoxicillin-clavulanic acid, with amoxicillin resistance ranging from 17.1% in P. buccae to 26.3% in P. denticola. Metronidazole resistance was <6% in all Prevotella species, while clindamycin resistance ranged from 0 to 21.1%. beta-Lactamase production was positive in 54.1% Prevotella spp., 38.9% F. nucleatum, 30% Capnocytophaga spp., and 10% Veillonella spp. In this study, amoxicillin-clavulanic acid was the most active antibiotic against all species tested, followed by metronidazole in the case of anaerobes.

Odontogenic bacteria in periodontal disease and resistance patterns to common antibiotics used as treatment and prophylaxis in odontology in Spain

La resistencia de los estreptococos o de las bacterias gramnegativas se asocia al consumo antibiótico, pero existe escasa información sobre la sensibilidad de los aislamientos de pacientes con periodontitis en los países con alto consumo de antibióticos, como es España; datos que pueden ser importantes cuando en la práctica diaria no se realizan determinaciones microbiológicas. En este estudio se analiza la sensibilidad de aislamientos de periodontitis a los antibióticos prescritos habitualmente en España en odontología para el tratamiento de infecciones locales o la profilaxis de infecciones a distancia. Se tomaron de forma prospectiva muestras periodontales de 48 pacientes clasificados, según la profundidad de la bolsa, en dos grupos: <4 mm y ≥ 4 mm. La identificación de las especies se realizó por PCR y por cultivo, seleccionando los cinco morfotipos más frecuentes en cada muestra. La sensibilidad antibiótica se determinó por E-test®. Se identificaron 261 cepas. El 72,9% de los pacientes presentaron Streptococcus oralis, el 70,8% Streptococcus mitis, el 60,4% Prevotella buccae, el 39,6% Prevotella denticola, el 37,5% Fusobacterium nucleatum, el 35,4% Prevotella intermedia, el 25% Capnocytophaga spp., el 23% Veillonella spp., el 22,9% Prevotella melaninogenica y Streptococcus sanguis, y <20% otras especies. Las tasas de resistencia de S. viridans fueron 0% a la amoxicilina, ≈10% a la clindamicina y 9% a 22% a la tetraciclina; se halló resistencia a la azitromicina entre el 18,2% de S. sanguis y el 47,7% de S. mitis. Los aislamientos de Prevotella fueron sensibles a la amoxicilina-ácido clavulánico. La resistencia a la amoxicilina osciló entre el 17,1% de P. buccae y el 26,3% de P. denticola. La resistencia al metronidazol fue <6% en las especies de Prevotella, mientras que a la clindamicina osciló entre un 0% y un 21,1%. El 54,1% de Prevotella spp., el 38,9% de F. nucleatum, el 30% de Capnocytophaga spp. y el 10% de Veillonella spp. eran productores de betalactamasas. Amoxicilina-ácido clavulánico fue el antibiótico más activo frente a todas las especies aisladas, seguido del metronidazol en el caso de los anaerobios

Resistance in streptococci or Gram-negative bacteria is associated with antibiotic consumption. Scarce information exists on the antibiotic susceptibility of bacterial isolates from patients with periodontitis in countries with high antibiotic consumption, as this is an area in which microbiological testing is not performed in daily practice. The present study was undertaken to explore the susceptibility of bacterial isolates in periodontitis to antibiotics prescribed in odontology in Spain as treatment for local infections or prophylaxis for distant focal infections. Periodontal samples were prospectively collected in 48 patients classified by pocket depth of <4 mm and ≥ 4 mm. Species were identified by culture, selecting the five most frequent morphotypes per sample, and polymerase chain reaction (PCR). Susceptibility was determined by E-test®. A total of 261 isolates were identified: 72.9% patients had Streptococcus oralis; 70.8% Streptococcus mitis; 60.4% Prevotella buccae; 39.6% Prevotella denticola; 37.5% Fusobacterium nucleatum; 35.4% Prevotella intermedia; 25% Capnocytophaga spp.; 23% Veillonella spp.; 22.9% Prevotella melaninogenica and Streptococcus sanguis; and <20% other species. Streptococcus viridans resistance rates were 0% for amoxicillin, ≈10% for clindamycin, 9-22% for tetracycline, and for azithromycin ranged from 18.2% for S. sanguis to 47.7% for S. mitis. Prevotella isolates were susceptible to amoxicillin-clavulanic acid, with amoxicillin resistance ranging from 17.1% in P. buccae to 26.3% in P. denticola. Metronidazole resistance was <6% in all Prevotella species, while clindamycin resistance ranged from 0 to 21.1%. β-Lactamase production was positive in 54.1% Prevotella spp., 38.9% F. nucleatum, 30% Capnocytophaga spp., and 10% Veillonella spp. In this study, amoxicillin-clavulanic acid was the most active antibiotic against all species tested, followed by metronidazole in the case of anaerobes