Bacteremia due to Pseudomonas aeruginosa: results from a 3-year national study in the Slovak Republic.

Risk factors, mortality and antimicrobial susceptibility of Pseudomonas aeruginosa bacteremias isolated from 148 patients from all University Hospitals in Slovakia were analyzed. Only 1.2% of 169 strains of P. aeruginosa were resistant to meropenem, 4.1% to piperacillin/tazobactam, 7.7% to ceftazidime as well as cefepime and 12% to amikacin. More than 30% of P. aeruginosa were resistant to ciprofloxacin. Our analysis of risk factors for antimicrobial resistance to the particular antimicrobials, indicated no difference in risk factors and outcome in cases infected with P. aeruginosa bacteremias resistant to amikacin, piperacillin/tazobactam or ceftazidime in comparison to episodes caused by P. aeruginosa due to susceptible isolates. When comparing risk factors for P. aeruginosa bacteremia in children vs. adults, cancer vs. non-cancer patients, several differences in risk factors were observed. Neither antimicrobial resistance to amikacin, ceftazidime or piperacillin/tazobactam, nor appropriateness of therapy according to two separate analyses were associated with better outcome.

Antifungal susceptibility of 262 bloodstream yeast isolates from a mixed cancer and non-cancer patient population: is there a correlation between in-vitro resistance to fluconazole and the outcome of fungemia?

The aim of this study was to test the antifungal susceptibility of 262 bloodstream yeast isolates (164 Candida albicans strain, 88 non-albicans Candida spp. and 10 non-Candida yeasts) recovered from 169 surgical, neonatal, critically ill intensive care unit patients (ICU), and cancer patients (mixed patient population) to amphotericin B (AmB), fluconazole (FLU), 5-flucytosine (5-FC), itraconazole (ITRA), ketoconazole (KETO), miconazole (MICO), and nystatin (NYS), in order to correlate in-vitro resistance to fluconazole with the outcome of fungemia. The agar disk diffusion test was used to assess the susceptibility of the 262 bloodstream yeasts isolates. In addition, 78 strains isolated from cancer patients were also tested with the E-test. There were no differences in the susceptibility of the various C. albicans strains tested, except in 40 isolates from surgery patients, which showed a somewhat lower susceptibility to KETO and MICO to (3.7-5.5% resistance). There were no C. albicans strains resistant to AmB, NYS, or FLU. There were slight differences in the susceptibility patterns of the 88 non-albicans Candida spp. (NAC) isolates. Resistance to AmB and NYS appeared in 1 strain of C. guillermondii (minimum inhibitory concentration; MIC to AmB; 4 microg/ml) and in 1 strain of C. parapsilosis (MIC to NYS, 8 microg/ml and MIC to AmB, 2 microg/ml). All other NACs were susceptible to both polyenes (AmB and NYS). Nine of the 11 strains of C. krusei were resistant to FLU (MIC >or= 64 microg/ml), the 2 exceptions showed, respectively, MICs for FLU of 6 and 32 microg/ml ("dose-dependent" susceptibility). However, only 2 of 29 C. glabrata strains were fully FLU-resistant (MIC >or= 64 microg/ml), 27 being susceptible with MIC values of 0.5-8 microg/ml. Apart from 9 C. krusei and 2 C. glabrata strains, 2 C. parapsilosis strains and 1 strain of C. tropicalis were also FLU-resistant. Among the 88 NACs, 17.04% were FLU-resistant and 3.7% were KETO- and ITRA-resistant. Resistance to 5-FC and AmB was minimal. We compared the outcomes of patients infected with FLU-resistant vs FLU-susceptible yeasts in 161 evaluable patients treated with FLU. Attributable mortality was significantly higher (19.0% vs 8.6%; P < 0.01) in patients infected with the FLU-resistant yeasts.