RESUMEN
The standardization of a rapid serum aminoglycoside assay using Enterobacter cloacae is described. This includes the sensitivity testing of the organism and its performance on various media, with Mueller-Hinton agar being the medium of choice. The precision and reproducibility of the assay, as measured by the within-run and between-run coefficients of variation, were 5.0 and 5.9, respectively. A significant positive correlation was obtained between the microbiologic assay for gentamicin and a 125I-labeled gentamicin radioimmunoassay with the use of both normal and uremic sera. When known amounts of gentamicin, tobramycin, and amikacin were added to antibiotic-free sera from normal persons, recovery rates of 80.0% to 97.9% were found. In the case of gentamicin, recovery rates of 85.0% to 97.9% were found with the use of sera from patients undergoing either hemodialysis or peritoneal dialysis. There were no effects on the recovery rates of the aminoglycosides from normal serum if high concentrations of clindamycin, methicillin, ampicillin, penicillin G, cephalothin, cefamandole or cefoxitin were also present in the sera. The newer cephalosporins, cefamandole and cefoxitin, had no in-vitro effect on the Kirby-Bauer sensitivity patterns of gentamicin, tobramycin, or amikacin, when tested against the assay organism.
Asunto(s)
Aminoglicósidos/análisis , Anticuerpos/análisis , Bioensayo/métodos , Enterobacter/efectos de los fármacos , Enterobacteriaceae/efectos de los fármacos , Agar , Aminoglicósidos/sangre , Anticuerpos/sangre , Medios de Cultivo , Gentamicinas/análisis , Gentamicinas/sangre , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
During 1978 there was a marked increase in the number of patients with meningococcal infection in the Hamilton area. Of 21 patients admitted to St. Joseph's Hospital, Hamilton, two thirds were under 5 years of age. Four patients died. All the isolates were sulfonamide-sensitive strains of serogroup B Neisseria meningitidis. Although no infections developed in contacts, several errors were made in the management of the hospital and household contacts of the infected patients: chemoprophylaxis was given to many contacts not considered to be at risk; ineffective antibiotics, particularly penicillin, were given for chemoprophylaxis; and chemoprophylaxis was often delayed while the results of cultures of nasopharyngeal and throat secretions were awaited. Circulation to local physicians of guidelines on proven prophylactic regimens was followed by a reduction in the frequency of these errors.
Asunto(s)
Infecciones Meningocócicas/epidemiología , Adolescente , Líquido Cefalorraquídeo/microbiología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Errores de Medicación , Infecciones Meningocócicas/tratamiento farmacológico , Infecciones Meningocócicas/microbiología , Neisseria meningitidis/aislamiento & purificación , Ontario , Penicilina G/uso terapéutico , Rifampin/uso terapéutico , Sulfadiazina/uso terapéuticoRESUMEN
Although physical incompatibility between heparin and a number of drugs has been reported we did not discover any evidence of such incompatibility when heparin was mixed with 11 commonly used drugs in therapeutic concentrations.Furthermore, there was no detectable change in the anticoagulant activity in the presence of any of these drugs, nor was there any change in the biological activity of the antibiotics tested.
Asunto(s)
Antibacterianos/farmacología , Ácido Ascórbico/farmacología , Coagulación Sanguínea/efectos de los fármacos , Heparina/uso terapéutico , Hidrocortisona/farmacología , Isoproterenol/farmacología , Lidocaína/farmacología , Cloruro de Potasio/farmacología , Complejo Vitamínico B/farmacología , Ampicilina/farmacología , Pruebas de Coagulación Sanguínea , Cefalotina/farmacología , Cloxacilina/farmacología , Interacciones Farmacológicas , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Pruebas de Sensibilidad Microbiana , Penicilina G/farmacología , Succinatos/farmacología , Tetraciclina/farmacologíaRESUMEN
The growth of Streptococcus pneumoniae in commercial media containing 14C-labeled substrates was studied experimentally; the results of blood cultures that were positive for S. pneumoniae over a 14-month period were analyzed to explain no-growth but radiometrically positive blood cultures from four patients with clinically diagnosed pneumococcal pneumonia. The growth of S. pneumonoiae in aerobic blood culture vials resulted in a chocolate color in the medium. S. pneumoniae grew rapidly in both aerobic and anaerobic media, but 14CO2 evolved from the metabolism of the labeled substrates was detected only in the aerobic culture vials. Radiometric detection lagged behind growth of the organisms and was accompanied by visual changes in the media. By 24 h, the viability of the culture was on the decline; radiometric readings remained positive even when the culture had died.
Asunto(s)
Neumonía Neumocócica/microbiología , Sepsis/diagnóstico , Streptococcus pneumoniae/crecimiento & desarrollo , Aerobiosis , Anaerobiosis , Sangre/microbiología , Medios de Cultivo , HemólisisRESUMEN
During 1975--77 Hemophilus vaginalis bacteremia occurred post partum in eight previously healthy women. Seven had been admitted for delivery at term and one because of threatened abortion. Six underwent cesarean section. Post-partum pyrexia and neutrophilia were the main features. All the patients recovered uneventfully while receiving antibiotics. H. vaginalis is an infrequent agent of bacteremia; it affects predominantly women after obstetric trauma.