ABSTRACT
The diverse clinical spectrum of meningococcal infections includes frequent clinical forms, such as meningitis or septicemia, and uncommon manifestations, such as septic arthritis. Neisseria meningitidis is not generally considered to be a causative agent of osteoarticular infections. We report the first case of acute primary cervical spondylitis in a 48-year-old man.
ABSTRACT
Incubation in CO(2) resulted in higher (> or =3 doubling dilution) MICs of telithromycin than those found in ambient air for 31.2% of 346 Streptococcus pneumoniae ermB-positive strains. An increased telithromycin MIC in CO(2) was not correlated with loss of its activity in the murine sepsis/peritonitis model.
Subject(s)
Anti-Bacterial Agents/pharmacology , Carbon Dioxide/pharmacology , Ketolides/pharmacology , Pneumococcal Infections/drug therapy , Protein Synthesis Inhibitors/pharmacology , Streptococcus pneumoniae/drug effects , Animals , Anti-Bacterial Agents/administration & dosage , Bacteremia/drug therapy , Bacteremia/microbiology , Disease Models, Animal , Humans , Ketolides/administration & dosage , Mice , Microbial Sensitivity Tests/methods , Peritonitis/drug therapy , Peritonitis/microbiology , Pneumococcal Infections/microbiology , Protein Synthesis Inhibitors/administration & dosageABSTRACT
The combination of quinupristin-dalfopristin (Q-D) and gentamicin was tested against two strains of gentamicin- and dalfopristin-susceptible methicillin-resistant Staphylococcus aureus (MRSA). One strain was susceptible to macrolides, lincosamides, and streptogramin B type antibiotics (MLS(B)), and the other was constitutively resistant to these antibiotics by virtue of the ermA gene. The checkerboard method and time-kill curves showed that the combination of Q-D and gentamicin was indifferent. A rabbit endocarditis model simulated the pharmacokinetics achieved in humans receiving intravenous injections of Q-D (7.5 mg/kg of body weight three times a day) and gentamicin (3 mg/kg once daily). For the MLS(B)-susceptible strain, a 4-day regimen reduced mean bacterial titers (MBT) in vegetations from 8.5 +/- 0.8 log CFU/g (control group) to 4.1 +/- 2.6 (gentamicin), 3.0 +/- 0.9 (Q-D), and 2.6 +/- 0.5 log CFU/g (Q-D plus gentamicin). For the strain constitutively resistant to MLS(B), a 4-day regimen reduced MBT in vegetations from 8.7 +/- 0.9 log CFU/g (control group) to 5.0 +/- 2.2 (gentamicin), 5.2 +/- 2.2 (Q-D), and 5.1 +/- 2.4 log CFU/g (Q-D plus gentamicin). The differences between control and treatment groups were significant for both strains (P < 0.0001), although there was no significant difference between treatment groups. No resistant variant was isolated from vegetations, and no significant difference in MBT in vegetations of treatment groups after 1-day regimens was observed. This experimental study found no additive benefit in combining Q-D and gentamicin against dalfopristin- and gentamicin-susceptible MRSA.
Subject(s)
Drug Therapy, Combination/therapeutic use , Endocarditis, Bacterial/drug therapy , Gentamicins/administration & dosage , Staphylococcal Infections/drug therapy , Virginiamycin/administration & dosage , Animals , Gentamicins/blood , Methicillin Resistance , Microbial Sensitivity Tests , Rabbits , Virginiamycin/bloodABSTRACT
The reliability of the BACTEC Mycobacteria Growth Indicator Tube (MGIT) 960 system for testing of Mycobacterium tuberculosis susceptibility to the three front-line drugs (isoniazid [INH], rifampin [RIF], and ethambutol [EMB]) plus streptomycin (STR) was compared to that of the BACTEC 460 TB system. The proportion method was used to resolve discrepant results by an independent arbiter. One hundred and ten strains were tested with an overall agreement of 93.5%. Discrepant results were obtained for seven strains (6.4%) with INH (resistant by BACTEC MGIT 960; susceptible by BACTEC 460 TB), for one strain (0.9%) with RIF (resistant by BACTEC MGIT 960; susceptible by BACTEC 460 TB), for seven strains (6.4%) with EMB (six resistant by BACTEC MGIT 960 and susceptible by BACTEC 460 TB; one susceptible by BACTEC MGIT 960 and resistant by BACTEC 460 TB), and for 19 strains (17.3%) with STR (resistant by BACTEC MGIT 960 and susceptible by BACTEC 460 TB). After resolution of discrepant results, the sensitivity of the BACTEC MGIT 960 system was 100% for all four drugs and specificity ranged from 89.8% for STR to 100% for RIF. Turnaround times were 4.6 to 11.7 days (median, 6.5 days) for BACTEC MGIT 960 and 4.0 to 10.0 days (median, 7.0 days) for BACTEC 460 TB. These data demonstrate that the fully automated and nonradiometric BACTEC MGIT 960 system is an accurate method for rapid susceptibility testing of M. tuberculosis.