RESUMEN
Bacterial adhesion is a crucial factor in the pathogenicity of numerous bacterial species. This property plays such a great role in infections of foreign material that removal of the material is the only effective therapy. The electron microscopy studies performed by Christensen have demonstrated that infected foreign material harbors bacteria which are often coated with slime and therefore escape detection by conventional microbiological methods. in view of these properties, enzymatic or physical detachment of adherent bacteria was attempted. 231 specimens from a variety of materials (catheters, heart valves, drains, bone biopsies) which yielded negative results after 15 days culture in Schaedler medium were either exposed to trypsin or sonicated. Among catheter specimens, 44.7% yielded positive bacteriologic results; pathogens recovered included 8.3% micrococci, 5.1% nongroupable streptococci, 1.7% group D streptococci, 2.9% Enterobacteria, and 23.3% coagulase-negative staphylococci. Among the bone specimens, the improvement in yield was 64.7%; except in one case, the pathogens recovered were consistent with previously initiated treatments. This bacterial detachment method should be studied in a larger number of specimens to determine its diagnostic value as compared with conventional techniques.
Asunto(s)
Adhesión Bacteriana/efectos de los fármacos , Osteomielitis/diagnóstico , Sonicación , Infecciones Estafilocócicas/diagnóstico , Tripsina/farmacología , Bioprótesis , Catéteres de Permanencia/efectos adversos , Enfermedad Crónica , Infecciones por Bacterias Grampositivas/diagnóstico , Infecciones por Bacterias Grampositivas/microbiología , Prótesis Valvulares Cardíacas/efectos adversos , Humanos , Técnicas In Vitro , Osteomielitis/etiología , Osteomielitis/microbiología , Estudios Retrospectivos , Infecciones Estafilocócicas/etiología , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/aislamiento & purificaciónRESUMEN
A better understanding of the pharmacokinetics of pefloxacin in human bone is warranted by the efficacy of this drug in the treatment of bone and joint infections. Surgical bone samples were taken at 30 mn, 1h, 6h, 12h and 24 h after the administration of a single 800 mg intravenous dose of pefloxacin over 1 hour for 26 patients who underwent surgery in an orthopedic surgery ward. Drug concentration was measured by a microbiological method (extraction of the antibiotic in buffer or with chloroform). Up until the 24th hour, in 25/26 cases, the bone levels were superior to 2 mg/l (the critical concentration of pefloxacin) in cortical as well as in spongy bone. Our study reveals a good diffusion of pefloxacin in bone, results which support the idea that this antibiotic may be prophylactically effective in orthopedic surgery.
Asunto(s)
Huesos/metabolismo , Pefloxacina/farmacocinética , Huesos/cirugía , Cloroformo , Difusión , Femenino , Humanos , Infusiones Intravenosas , Masculino , Pefloxacina/administración & dosificación , Pefloxacina/análisis , Infección de la Herida Quirúrgica/prevención & controlRESUMEN
Because of its pharmacokinetic, broad spectrum and oral administration, ofloxacin can be used in the treatment of chronic bone infections. A clinical trial was performed in 10 patients with subacute or chronic osteitis (5 Staphylococcus aureus, 1 Staphylococcus epidermidis, 1 Klebsiella oxytoca, 1 Escherichia coli, 1 Serratia marcescens, 1 Pseudomonas aeruginosa). Patients were given orally 200 mg 12 hourly. Treatment duration went on from 2 to 6 months. In this trial, the evaluation was successful in the 10 cases with a delay of 2 to 13 months (m 8,9) after the end of the treatment. Prosthetic material has been taken off in 1 case out of 4 patients (prosthetic hip) because of persistaet free bacteria outflow. For one patient, a superinfection with a Pseudomonas aeruginosa resistant to ofloxacin was noticed at the second month. Bone levels (microbiological method) were between 1,3 and 9,7 mg/l and always higher to the MIC of the bacteria. Biological tolerance was satisfactory in spite of a rise of transaminase level, a transient renal disfunction whom relationship to the treatment was difficult. 3 transient photosensitivities were also noticed.
Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Osteítis/tratamiento farmacológico , Oxazinas/uso terapéutico , Adolescente , Adulto , Anciano , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Ofloxacino , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones Estafilocócicas/tratamiento farmacológicoRESUMEN
Levels of an aminoglycoside, dibekacin, are studied in bone. Fifteen specimens were obtained by Tanzer trocar biopsy three hours after the ninth injection of dibekacin (1 mg/kg). Separation of cortical and spongy bone was not feasible owing to the small weight of specimens. Dibekacin concentrations were determined by microbiological assay. These concentrations were evaluated using a reference range in bone tissue determined with the same method and must be corrected according to blood levels. Dibekacin levels were 0.22 +/- 0.10 mg/l in healthy, non- contaminated specimens, and 1.70 and 1.80 mg/l in infected bone tissue.