In vitro activity of sitafloxacin compared with several fluoroquinolones against Streptococcus anginosus and Streptococcus constellatus.

The in vitro activities of sitafloxacin and seven other fluoroquinolones a (ciprofloxacin, tosufloxacin, sparfloxacin, levofloxacin, T-3811ME, moxifloxacin and trovafloxacin) were examined by the microdilution method against 79 clinically isolated 'Streptococcus milleri' group (SMG) microorganisms. No statistically significant differences were found between the minimum inhibitory concentrations (MIC(50) and MIC(90)) against Streptococcus anginosus and Streptococcus constellatus. Sitafloxacin was the most active agent of the eight fluoroquinolones tested against SMG, with a MIC(90) of 0.06 microg/mL, which was 8 times more active than ciprofloxacin and 16 times more active than levofloxacin. Although none of the SMG strains showed high resistance to any of the fluoroquinolones tested, three agents (trovafloxacin, sitafloxacin and T-3811ME) had low MICs against 23 SMG strains against which levofloxacin had a MIC> 1 microg/mL. In conclusion, several fluoroquinolones have low MICs against SMG, but sitafloxacin has the lowest.

In vitro activity of pazufloxacin, tosufloxacin and other quinolones against Legionella species.

OBJECTIVES: The activities of pazufloxacin and tosufloxacin against Legionella spp. were evaluated in vitro and compared with those of other quinolones, macrolides and azithromycin. METHODS: The conventional MICs were determined by the microbroth dilution method. Intracellular activities of drugs were evaluated by a cfu count. The minimal extracellular concentration inhibiting intracellular growth of bacteria (MIEC) was determined by a colorimetric cytopathic assay. RESULTS: MICs of pazuloxacin and tosufloxacin at which 90% (MIC90) of isolates are inhibited in 76 different Legionella spp. strains (38 ATCC strains and 38 clinical isolates) were 0.032 and 0.016 mg/L, whereas the MIC90s of levofloxacin, ciprofloxacin, garenoxacin, erythromycin, clarithromycin and azithromycin were 0.032, 0.032, 0.032, 2.0, 0.125 and 2.0 mg/L, respectively. Pazufloxacin and tosufloxacin at 4x MIC inhibited intracellular growth of Legionella pneumophila SG1 (80-045 strain), as did other quinolones, clarithromycin and azithromycin, whereas erythromycin at 4x MIC did not. MIECs of pazufloxacin, tosufloxacin, levofloxacin, ciprofloxacin and garenoxacin for the strain were 0.063, 0.004, 0.016, 0.032 and 0.008 mg/L respectively, which were superior to those of macrolides and azithromycin. Pazufloxacin showed potent activity against three additional clinical isolates of L. pneumophila SG1, one clinical isolate each of L. pneumophila SG3 and SG5, as well as Legionella micdadei, Legionella dumoffii and Legionella longbeachae SG1. CONCLUSIONS: Pazufloxacin and tosufloxacin, as well as other quinolones, were more potent than macrolides and an azalide. Present data warrant further study on the efficacy of these drugs in the treatment of Legionella infections.

Isolation of Legionella anisa from multiple sites of a hospital water system: the eradication of Legionellacontamination.

For the prevention of nosocomial cases of legionellosis in the Ryukyu University Hospital neonatal wards, we examined nine shower units and a sink tap water unit for the presence of Legionella, over a 6-year period. We isolated Legionella-like organisms (LLO) from showerheads by culturing sediments from the water samples on buffered charcoal yeast extracts (BCYE). We used DNA-DNA hybridization to determine that the organisms were L. anisa. A fingerprinting technique called random amplified polymorphism DNA (RAPD) also showed that all the organisms were identical at the genome level. Replacement of the shower heads harboring colonies of L. anisa prevented further contamination. Nosocomial cases of legionellosis have not been reported from the wards during the period of this survey. This is the first description of the isolation of L. anisa from multiple sites within a hospital, and RAPD analysis suggests that these may be the spread of a single clone.

[A case of disseminated aspergillosis with smoldering adult T-cell leukemia].

The patient was 39-year-old male who had been administrated 20 mg of prednisolone for control of chronic eosinophilic pneumonia. He consulted the hospital with fever, headache and gait disturbance. The laboratory data of peripheral blood revealed a smoldering adult T cell leukemia. Computed tomogram of the chest and MRI of the brain revealed a mass in the right middle lobe of the lung and a brain abscess in the left hemisphere respectively. Biopsied specimens from the lung and brain abscess showed an Aspergillus like fungus. In spite of placement of an Ommaya reservoir for administration of AMPH-B and control of intracranial pressure, he died. During the course, specific antigen and specific gene were not detected in the peripheral blood, and no viable organism was isolated from the specimens. Post mortem examination revealed multiple nodular lesions in the lung, parietal pleura, liver, heart and kidney. After autopsy, disseminated aspergillosis was confirmed through a tissue examination using nested PCR for Aspergillus DNA. In this case, we think that viable fungi could endure in the tissue while circulating Aspergillus markers remained undetectable.

Trends in antimicrobial susceptibility of the Streptococcus milleri group.

A collection of 114 clinical Streptococcus milleri group (SMG) strains at the Ryukyu University Hospital obtained in 1999 and 2000, was identified and tested for susceptibility to 12 antibiotics. The percentage of strains with intermediate susceptibility to penicillin G was relatively high (14%). Cefaclor and cefotiam, with a MIC 90 of 2 microg/ml, were less active than cefotaxime. Strains nonsusceptible to erythromycin, clindamycin, and azithromycin were found with a frequency of 8%, 5%, and 4%, respectively. Almost all of the SMG strains were susceptible to fluoroquinolones (except for 1% of the strains nonsusceptible to levofloxacin), and sitafloxacin (DU-6859a) was the most active agent among the 12 tested antibiotics.