[Multicenter surveillance of Pseudomonas aeruginosa strains for antimicrobials in Aichi prefecture in 2009].

We investigated the susceptibility to antimicrobials of 204 Pseudomonas aeruginosa strains isolated from 21 hospitals in Aichi prefecture from September to November 2009. MIC distributions of various antimicrobials were analyzed in terms of geographic region of isolation, patient status (outpatient or inpatient), and type of specimens that the strain was isolated from. The results were as follows. 1. Although more than 90% of strains were susceptible to all aminoglycosides and colistin, 80-90% of them were susceptible to beta-lactams and fluoroquinolones. MIC distributions of all antimicrobials measured were not significantly different between regions. 2. Only 1 strain (0.5%) was multi-drug resistant Pseudomonas aeruginosa (MDRP). Thirteen strains (6.4%) showed imipenem MIC > or = 16 microg/mL, and 16 strains (7.8%) showed ciprofloxacin MIC > or = 4 microg/mL. These strains tended to be more isolated from urine, respiratory tract specimens, or surgical specimens. 3. The MICs of tazobactam/piperacillin, panipenem, meropenem, doripenem, biapenem, sulbactam/cefoperazone, cefepime, and aztreonam were significantly higher in strains isolated from inpatients than in those from outpatients. MIC distributions of antimicrobials other than beta-lactams were not significantly different between situations where strains were isolated. 4. MIC distributions of piperacillin, all carbapenems, cefepime, gentamicin, and all fluoroquinolones were significantly different among samples from which strains were isolated. The strains isolated from blood showed lower MICs against all antimicrobials than those from other samples. No difference was found in MIC distributions when categorized according to bacteremic origin. The MICs were apparently elevated against beta-lactams, fluoroquinolones, and gentamicin in strains isolated from respiratory tract specimens, and against beta-lactams, and fluoroquinolones in strains isolated from urine. It was suggested that in P. aeruginosa surveillance, the results should be reported by stratifying with patient status, and type of specimens that the strain was isolated from and that regional surveillance should be useful with such stratification to establish antibiograms for empirical antimicrobial choice.

Treatment effects and predictors of a 24-week course of interferon alpha-2b plus ribavirin combination therapy for patients with chronic hepatitis C.

BACKGROUND AND AIMS: In chronic hepatitis C patients with genotype 1b and a high viral load, the sustained virological response (SVR) rate remained as low as 2-3% with conventional interferon (IFN) monotherapy, but improved to more than 20% with IFN alpha-2b plus ribavirin combination therapy. This study examined the therapeutic effects and predictors of this combination therapy. METHODS: Subjects were 105 patients with chronic hepatitis C (73 males, 32 females) with a median age of 53 years (range 19-70 years). Seventy-two patients had genotype lb and 33 patients had genotype 2 (2a or 2b). Six million units (MU) or 10 MU of IFN alpha-2b was administered by intramuscular injection six times a week for the first 2 weeks, and the same amount of IFN was administered three times a week for the following 22 weeks. During the IFN administration period, 600-800 mg of oral ribavirin was administered daily. Patients who were hepatitis C virus (HCV)-RNA negative 24 weeks after the completion of administration were defined as SVR. RESULTS: The overall SVR rate was 39%; 22.2% for the genotype 1b group and 75.8% for the genotype 2 group, and the difference between the groups was significant (P < 0.0001). Multivariate logistic regression analysis indicated that the factors that contributed to SVR include genotype 2, age (younger than 53 years), and an increase in Th2 measured by flow cytometry before and 4 weeks after start of treatment. CONCLUSIONS: The overall SVR rate of IFN alpha-2b plus ribavirin combination therapy for 24 weeks was 39%, and contributing factors for SVR rate include genotype 2, age younger than 53 years and elevated Th2.