In vitro interference of beta-lactams with biofilm development by prevalent community respiratory tract isolates.

Interference of cefditoren (CDN) and amoxicillin/clavulanic acid (AMC) with biofilm production was studied using 11 Streptococcus pneumoniae isolates with minimum inhibitory concentrations (MICs) ranging from 0.015microg/mL to 0.5microg/mL for CDN and from 0.06microg/mL to 2microg/mL for AMC (except for one isolate with an AMC MIC of 8microg/mL) and 5 Haemophilus influenzae isolates with MICs of 0.03-0.06microg/mL for CDN and 0.5-16microg/mL for AMC. Slime production was assessed in antibiotic-free medium and with 0.03microg/mL CDN or 1/0.5microg/mL AMC by measuring the optical density at 450nm (OD(450)). Significantly lower mean OD(450) values were obtained for S. pneumoniae with antibiotics compared with controls (CDN, 0.088 vs. 0.118, P=0.003; and AMC, 0.095 vs. 0.112, P=0.003), with significant correlation between both antibiotics (r=0.752; P=0.008). Percent reduction in OD(450) values was higher for CDN compared with AMC (24.02% vs. 15.92%; P=0.008). For H. influenzae, significantly lower mean OD(450) values were obtained with CDN compared with controls (0.083 vs. 0.096; P=0.043) but not with AMC (0.086 vs. 0.095; P=0.08). Comparing percent reductions in S. pneumoniae versus H. influenzae for each antibiotic, no differences were found for AMC (15.92% vs. 9.40%; P=0.36), with a tendency for CDN (24.02% vs. 13.79%; P=0.069). Different beta-lactams may have different capabilities of interfering with S. pneumoniae biofilm development when tested under the same experimental conditions.

Tinidazole inhibitory and cidal activity against anaerobic periodontal pathogens.

The in vitro activity of tinidazole against anaerobic periodontal pathogens (25 Prevotella buccae, 18 Prevotella denticola, 10 Prevotella intermedia, 6 Prevotella melaninogenica, 5 Prevotella oralis, 10 Fusobacterium nucleatum and 8 Veillonella spp.) was determined by agar dilution. MIC(90) values (minimum inhibitory concentration for 90% of the organisms) were 8 microg/mL for Veillonella spp., 4 microg/mL for P. intermedia, 2 microg/mL for P. buccae, 1 microg/mL for Fusobacterium spp. and 0.5 microg/mL for other Prevotella spp. Cidal activity was studied by killing curves with tinidazole and amoxicillin (alone and in combination) at concentrations similar to those achieved in crevicular fluid (41.2 microg/mL tinidazole and 14.05 microg/mL amoxicillin) against an inoculum of ca. 10(7)colony-forming units/mL of four bacterial groups, each one composed of four different strains of the following periodontal isolates: Prevotella spp., Fusobacterium spp. and Veillonella spp. (anaerobes) and one amoxicillin-susceptible Streptococcus spp. (facultative) in a proportion of 1:1:1:1. When only beta-lactamase-negative Prevotella or Fusobacterium strains were tested, significantly higher reductions were found with amoxicillin (>4 log reduction at 48 h) versus controls. The presence of beta-lactamase-positive Prevotella spp. or F. nucleatum strains rendered amoxicillin inactive (no reductions at 48 h), with no differences from controls. Amoxicillin+tinidazole produced >3 log reduction at 24h and >4 log reduction at 48 h regardless of the presence or not of beta-lactamase-positive strains. The presence in crevicular fluid of beta-lactamases produced by beta-lactamase-positive periodontal pathogens may have ecological and therapeutic consequences since it may protect beta-lactamase-negative periodontal pathogens from amoxicillin treatment. In vitro, tinidazole offered high antianaerobic activity against beta-lactamase-positive and -negative periodontal pathogens, avoiding amoxicillin inactivation.

[Bacteremia after periodontal procedures]. / Bacteriemia secundaria a procedimientos odontológicos periodontales.

INTRODUCTION: Bacteremia frequently occurs after oral surgery and odontology procedures. Periodontitis may affect the incidence and bacterial spectrum of bacteremia. Periodontal disease may be a significant risk factor for the development of certain systemic diseases. This study has aimed to evaluate the frequency of aerobic and anaerobic bacteria in the bloodstream following scaling and root planing. MATERIAL AND METHODS: Thirteen patients with generalized chronic periodontitis were included in the study. Two samples of peripheral blood were drawn for culture at different times: pre-treatment and immediately after odontology treatment (full-mouth scaling). RESULTS: None of the 13 patients had bacteremia before the procedures. Bacteremia after scaling occurred in 10/13 (76.9 %) of periodontitis patients. The anaerobic bacteria (Prevotella spp., Micromonas micros and Fusobacterium nucleatum) were the most predominant microorganism. CONCLUSIONS: Our findings suggest that periodontal procedures induce bacteremia and may represent risk of developing systemic complications. The use of antibiotic prophylaxis is crucial for its prevention.

Strong slime production is a marker of clinical significance in Staphylococcus epidermidis isolated from intravascular catheters.

Biofilm production was assessed in 52 Staphylococcus epidermidis isolates from the catheters of 52 patients with catheter-related bloodstream infections (CR-BSI) and compared with 14 isolates from the skin of healthy volunteers by spectrophotometry. The isolates were classified as non- (G1), weak- (G2) or strong- (G3) slime producers based on optical density, and as producers and non-producers based on the results of the Congo red agar test. Differences (p = 0.012) in the proportion of G1, G2 and G3 among the isolates were found between catheter and healthy skin strains: there was a higher percentage of G1 types among the healthy skin strains (35.7 vs. 11.5%; p = 0.046) and a higher percentage of G3 types among the catheter isolates (44.2 vs. 0%; p = 0.001). No significant differences were found with the Congo red agar test. G3 is a phenotypic marker for CR-BSI.

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

Candidemia no detectada por un sistema automatizado de monitorización de hemocultivos. A propósito de un caso / Undetected candidemia by a monitoritation automatic bloodculture system. Concerning a clinical case

No disponible

[Contribution to the early diagnosis of bacteremia: microbial growth detection in liquid culture media by ultrasound]. / Contribución al diagnóstico precoz de bacteriemia: detección del crecimiento microbiano en medios de cultivo líquidos por ultrasonidos.

Nosocomial infection is an important problem because the number of patients daily affected in big hospitals. A big effort exists to develop techniques able to early detect the micro-organisms which cause the infection. The ultrasound is a mechanical radiology technique widely used in Medicine for diagnosis and therapy. It is also well known that this radiation can be used to control relative changes of several physico-chemical parameters in liquids. As an example, the velocity an attenuation of acoustic waves coming through a liquid can be accurately measured. The developed technique consists of an ultrasonic chamber immersed into a thermostatized water bath with two transducers operating in through-transmission. Different culture bottles were placed in between the transducers to live the ultrasound to come across the sample. Several micro-organisms with controlled concentrations, chosen between the most common in sepsis clinical, were used to inoculate each bottle. In the case of aerobic metabolism, the carbon dioxide gas produced by bacteria introduce elastic changes into the liquid which modify both the propagation velocity and the attenuation of the ultrasound. The continuous monitoring of the time-of-flight and the amplitude of an ultrasonic pulse coming through the sample give us a clear indication of the metabolism process. The signatures observed permits the identification of algorithms to early define the positive cases. The developed technique is faster than other commercial systems. The intrinsically non-invasive characteristic of the ultrasound and the relative cheapness of the technique open new attractive possibilities in microbiological diagnosis.

[Staphylococcus lugdunensis infection: Report of thirteen cases]. / Infección por Staphylococcus lugdunensis: presentación de trece casos.

INTRODUCTION: Staphylococcus lugdunensis is a coagulase-negative staphylococcus associated with infections such as aggressive endocarditis, repeated abscess formation and opportunist infections. MATERIALS AND METHODS: S. lugdunensis isolates recovered at our hospital during three years (1997-2000) were studied. The fibrinogen affinity factor and tube free-coagulase were analysed. The identification was made by the Crystal GPID (Becton-Dickinson) and Wider (Soria Melguizo) systems. Antibiotic sensitivity testing was performed with Wider panels. The clinical records of patients with S. lugdunensis recovered were studied. RESULTS: Thirteen S. Lugdunensis isolates were recovered from the following sources: abscess (9), surgical wound (2), blood culture (1), and urine (1). In ten cases the microorganism was obtained in pure culture; in the remaining three cases, S. lugdunensis grew in mixed culture. Two cases were excluded, as S. lugdunensis was considered not to be associated with the clinical condition. Lesions were located at: inguinal region (4), gluteal region (2), breast (2), abdominal wall (1), foot (1), unknown (1). Tent of the 13 isolates (76%) had fibrinogen affinity factor. Penicillin sensitivity was observed in 11/13 strains (84.6%). In one case, the isolate was beta-lactamase producer (7.6%); and in other case, the isolate was resistant to methicillin (7.6%). CONCLUSIONS: In this study we observed that S. lugdunensis is associated with skin and soft tisue infections, particularly abscess formation. The infection occurs most frequently in cancer patients, as observed in three cases in our series. The necessity of correctly identifying S. Lugdunensis is underscored. The recovery of coagulase-negative staphylococci should not reassure us unless a potentially pathogen species has been ruled out.

Consideraciones sobre el aislamiento en exudados vaginales de Streptococcus morbillorum / The isolation of Streptococcus morbillorum from vaginal exudates

De el estudio de 195 exudados vaginales enviados por el Servicio de Ginecologia de este hospital, durante el periodo 1988-1990, hemos seleccionado aquellos en los que el cultivo fue positivo para estreptococos, 58 (30 por ciento) de los cuales 26 (44.8 por ciento) correspondia a Streptococcus morbillorum, 9 (15.5 por ciento) a Gardnerella vaginalis, 5 (8.6 por ciento) a Enterococcus faecalis-durans, y a Streptococcus agalactiae, 3 (5.1 por ciento) a Streptococcus mitis y Styreptococcus milleri, 2 (3.4 por ciento) a Streptococcus bovis y Streptococcus cremoris y 1 (1.7 por ciento) a Streptococcus salivarius, Streptococcus equinus y Strptococcus sanguis II respectivamente. En todos los casos se observó antecedentes de actuacción medicoquirurjica en el tracto genital, y en el 52,8 por ciento de los casos fuè concomitante con el diagnostico clinico-micologico de candidiasis vaginal. La identificacción bacteriologica se realizó mediante el sistema API 20 STREP (sistema api bioMérieux GmbH, Nüttingen, Alemania) dando un patron tipico ("excelente identificacción") para el Streptococcus morbillorum.

[The isolation of Streptococcus morbillorum from vaginal exudates]. / Consideraciones sobre el aislamiento en exudados vaginales de Streptococcus morbillorum.

We have tested 195 vaginal secretions sent by Gynecology Service of this hospital between the years 1988-1990. We achieved positive culture for streptococci in 58 (30%) of these cultures, 26 (44.8%) corresponding to Streptococcus morbillorum 9 (15.5%), to Gardnerella vaginalis 5 (8.6%), to Enterococcus faecalis-durans and to Streptococcus agalactiae, 3 (5.1%) to Streptococcus mitis and milleri 2 (3.4%), to Streptococcus bovis and cremoris, and 1 (1.7%) to Streptococcus salivarius, equinus and sanguis II respectively. We previously found that 52.8% of these patients were positive for vaginal candidiasis. The bacteriological identification done by the API 20 STREP System (bioMerieux GmbH, Nútingen, Germany) provides a typical pattern ("good identification") for the Streptococcus morbillorum.

[Localized scleroderma (morphea) and septic arthritis. Clinical manifestations of Lyme borreliosis seen in El Ferrol]. / Esclerodermia localizada (morfea) y artritis séptica. Manifestaciones clínicas de borreliosis de Lyme observadas en El Ferrol.

Two cases of Lyme's disease seen at El Ferrol (Spain) were described. One of them developed a recurrent knee arthritis and the other had a localized sclerodermia (morphea) syndrome. Diagnosis was established by means of clinical picture and serologic tests (enzyme-linked analysis and/or indirect immunofluorescence tests). Joint involvement has often been described in patients diagnosed of having Lyme's disease in Spain, however, the relationship between morphea and borreliosis is still a matter of controversy. We believe that patients with localized sclerodermia and high significant titers of specific antibodies against B. burgdorferi should be treated with antimicrobial agents.

[Milker's nodes: transmission by fomites and virological identification]. / Nódulos de los ordeñadores: transmisión por fomites e identificación virológica.

We report a case of milker's nodules in a male who was not a professional cattle raiser with indirect and accidental transmission by fomites. A parapoxvirus was demonstrated from cutaneous lesions by electron microscopy with negative stain.