[Analysis of clinical characteristics and risk factors associated with prognosis of patients with candidemia].

OBJECTIVE: To explore the microbiological and clinical characteristics of patients with candidemia and analyze their prognostic risk factors. METHODS: A retrospective analysis was conducted for hospitalized patients with candidemia from January 2008 to December 2012 at Affiliated Zhongshan Hospital, Fudan University. Pathogen spectrum, resistance pattern, underlying diseases, therapy received and patient prognosis were collected by chart review. The univariate and multivariate Logistic regression analyses were used to determine the prognostic risk factors of candidemia. RESULTS: A total of 138 inpatients were identified. There were 98 males and 40 females with a mean age of (61.3 ± 16.6) years. The morbidity rate of candidemia in annual discharged patients was 0.034%-0.051%. The most common pathogens were Candida albicans (n = 72, 52.2%), Candida parapsilosis (n = 29, 21.0%) and Candida tropicalis (n = 16, 11.6%). The antibiotic susceptible rate of azole for Candida was 90.9%-97.4% while 55.6%-83.3% for Candida tropicalis. The overall case fatality rate of candidemia was 39.1% (54/138) while the attributable case fatality rate 31.9% (44/138). Multivariate Logistic regression analysis indicated acute physiology and chronic health evaluation II(APACHE II) score ≥ 20 points (OR = 8.025, 95%CI: 2.032-31.696, P = 0.003), hypoproteinemia (OR = 6.213, 95%CI: 1.849-20.879, P = 0.003), concurrent bacteremia (OR = 5.541, 95%CI: 1.576-19.487, P = 0.008) and indwelling urethral catheter (OR = 13.776, 95%CI: 1.402-135.352, P = 0.024) were the independent risk factors of candidemia-related mortality, while removal or replacement of central venous catheter (OR = 0.231, 59%CI: 0.075-0.716, P = 0.011) and surgery within 30 days (OR = 0.206, 95%CI: 0.050-0.857, P = 0.030) were the protective factors. CONCLUSIONS: Candida albicans is the most common causative agent. The case fatality rate of candidemia has remained high. APACHE II score ≥ 20 points, hypoproteinemia, indwelling urethral catheter and concurrent bacteremia are independent risk factors attributing to candidemia-related mortality while removal or replacement of central venous catheter and surgery within 30 days are the protective ones.

[Activity of macrolides and fluoroquinolones against intracellular Legionella pneumophila].

OBJECTIVE: To evaluate the activity of macrolides and fluoroquinolones against Legionella pneumophila by intracellular susceptibility testing. METHODS: Minimum inhibitory concentration (MIC) was determined by standard agar dilution test according to the CLSI. For intracellular assays, legionella pneumonia was used to infect human monocytic cell line THP-1. Erythromycin, azithromycin, levofloxacin and moxifloxacin at 1 × MIC, 4 × MIC, 8 × MIC were added following phagocytosis. Number of viable bacteria was enumerated at 24 h on BCYE (buffered charcoal yeast extract) agar in duplicates using standard plate count method. The result was expressed as percentage inhibition. Mann-Whitney U test was used to determine the significant differences in mean percentage inhibition between agents. RESULTS: Percentage inhibition at 24 h were as follows: Erythromycin 1 × MIC (50.18 ± 27.29)%, 4 × MIC (79.48 ± 20.08)%, 8 × MIC (91.46 ± 8.70)%; Azithromycin 1 × MIC (66.77 ± 26.18)%, 4 × MIC (91.73 ± 8.72)%, 8 × MIC (97.10 ± 3.37)%; Levofloxacin 1 × MIC (99.84 ± 0.25)%, 4 × MIC (99.99 ± 0.02)%, 8 × MIC (99.99 ± 0.01)%; Moxifloxacin 1 × MIC (99.90 ± 0.10)%, 4 × MIC (99.99 ± 0.03)%, 8 × MIC (99.99 ± 0.03)%. The fluoroquinolones showed greater inhibitory activity than macrolides against legionella pneumophila(u = 1.0, 2.0, 5.0, P < 0.05). Levofloxacin and moxifloxacin had the same intracellular activity against legionella pneumophila (u = 190, 183, 217, P > 0.05). Azithromycin was more effective than erythromycin in inhibiting intracellular legionella pneumophila (u = 132, 125, 128, P < 0.05). CONCLUSIONS: The fluoroquinolones were more active than macrolides against legionella pneumophila. The intracellular activity of levofloxacin against legionella pneumophila appeared to be similar to moxifloxacin. Azithromycin was demonstrated to have superior activity against legionella pneumophila compared with erythromycin.

[Genetic diversity of Legionella pneumophila serogroup 1 in hospital water distribution systems in Shanghai].

OBJECTIVE: To classify Legionella pneumophila serogroup 1 (LP1) isolated from the water distribution systems in hospitals of Shanghai by using genotying methods, and therefore to explore the genetic relationship between different genotypes. METHODS: LP1 was isolated from 8 hospitals in Shanghai, and strains of LP1 were subtyped using pulse field gel electrophoresis (PFGE). Genotyping results of PFGE were classified as dendrogram, and cluster analysis was used to compare the genetic characteristics of different strains. RESULTS: Twenty-four strains of LP1 were isolated from 193 water specimens. LP1 belonged to 6 PFGE genotypes, of which 21 belonged to 3 predominant genotypes. Different hospitals shared the same genotype, while some strains isolated from the same hospital had different genotypes. CONCLUSION: The genetic characteristics are stable in environmental LP1. Molecular biology techniques should be added to epidemiological study for hospital acquired legionellosis due to the genetic diversity in one hospital.