ABSTRACT
We studied the bioactivity of vancomycin and tobramycin eluted from methylmethacrylate bone cement. Aliquots of the drainage were obtained at 1, 6, 12 and 24 hours following total hip prosthetic implantation with vancomycin-tobramycin-loaded cement in 3 patients. The samples were analyzed with fluorescence polarization immunoassay and bioassay, using group B streptococcus for vancomycin and Escherichia coli for tobramycin. These bacteria were selected due to the effectiveness of vancomycin and poor effectiveness of tobramycin against group B streptococcus and conversely with E. coli. The immunodetection of vancomycin averaged 14 (1 hour), 9 (6 hours), 10 (12 hours) and 11 microg/mL (24 hours). The bioassay averaged 47, 36, 79 and 41 microg/mL (p = 0.03). The immunodetection of tobramycin averaged 43, 21, 18 and 14 microg/mL; and bioassay 30, 15, 15 and 12 microg/mL (p = 0.1). Both antibiotics eluted with a highly effective bactericidal activity. Our findings indicate that the presence of tobramycin has a synergistic-like effect on the bactericidal activity of vancomycin, which has not been previously reported. We recommend a combination of vancomycin and tobramycin with cement for the treatment of orthopedic infections caused by gram-positive organisms.
Subject(s)
Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacology , Arthroplasty, Replacement, Hip , Bone Cements , Tobramycin/administration & dosage , Tobramycin/pharmacology , Vancomycin/administration & dosage , Vancomycin/pharmacology , Aged , Aged, 80 and over , Biological Assay , Escherichia coli/drug effects , Female , Gentamicins/pharmacology , Humans , Male , Methylmethacrylate , Middle Aged , Radioimmunoassay , Streptococcus agalactiae/drug effectsABSTRACT
There has been controversy in the health professions about the necessity for newborn infant hearing screening. It is well accepted that patient history or a birth that places the infant in the high-risk registry (HHR) can identify 50 of all infants born with permanent bilateral hearing loss. Two major factors which have been cited as reasons for not screening the well-baby nursery have been poor cost effectiveness and the lack of documentation as to the benefits derived from early identification and intervention. Recent technological developments and published data are presented which indicate that economical well-baby hearing screening can be done in any setting, and that the language acquisition of the infant is permanently affected if the intervention is not done in the first six months after birth
Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Hearing Tests , Neonatal Screening , Hearing Loss/diagnosis , Age of Onset , Cost-Benefit Analysis , United States/epidemiology , Hearing Loss/economics , Hearing Loss/epidemiology , Puerto Rico/epidemiology , Hearing Tests/economics , Hearing Tests/instrumentation , Hearing Tests , Language Disorders/economics , Language Disorders/epidemiology , Language Disorders/etiology , Learning Disabilities/economics , Learning Disabilities/epidemiology , Learning Disabilities/etiology , Neonatal Screening/economics , Neonatal Screening/instrumentation , Neonatal ScreeningABSTRACT
There has been controversy in the health professions about the necessity for newborn infant hearing screening. It is well accepted that patient history or a birth that places the infant in the high-risk registry (HHR) can identify 50% of all infants born with permanent bilateral hearing loss. Two major factors which have been cited as reasons for not screening the well-baby nursery have been poor cost effectiveness and the lack of documentation as to the benefits derived from early identification and intervention. Recent technological developments and published data are presented which indicate that economical well-baby hearing screening can be done in any setting, and that the language acquisition of the infant is permanently affected if the intervention is not done in the first six months after birth.