RESUMO
Candiduria is a common and high risk event in patients with uropathies and cancer. In this study we investigated the distribution of 3 virulence factors namely: biofilm formation [BF], secreted aspartyl proteinase [SAP] and phospholipase activity [PLA] among different Candida species isolated from inpatients with candiduria. The susceptibility patterns of Candida isolates to antifungal agents, including the new voriconazole, were evaluated in vitro and the association of these virulence factors with resistance was studied. Urine specimens from 250 patients divided into 3 groups were examined: Group1 [n=50] cancer bladder; Group2 [n=100] obstructive uropathy and Group 3 [n=100] simple recurrent urinary tract infection [UTI]. Candida isolates were identified by CHROM-agar, and by Candifast Es Twin test. Susceptibility testing to antifungal agents was evaluated by disc diffusion test using fluconazole [FCZ] 30microg discs and E test strips for Minimum inhibitory concentration [MIC] determination of FCZ, voriconazole [VCZ] and Amphotericin B [AMB]. Assessment of BF was performed by tube and spectrophotometric plate adherence methods and quantitated by crystal violet staining and XTT reduction assays. PLA was screened using Sabouraud egg yolk agar and SAP was detected using bovine serum albumin agar [BSA]. The overall prevalence of candiduria was 24% with highest incidence among obstructive uropathy patients [67.2%]. Isolation rate of Candida [C]. nonalbicans species [C. tropicalis ,C. krusei and C. glabrata] was significantly higher than C. albicans [73.1% versus 26.8%; p256microg/ml]. Voriconazole, the new triazole antifungal agent, was active against all isolated Candida species with a sensitivity rate of 82%-100% and low MIC values [0.064-1microg/ml] except in C. glabrata species [22%]. All isolated Candida species were more sensitive to VCZ compared to FCZ; particularly C. krusei isolates [90% versus 9%]. AMB remained to be an effective drug with absolute sensitivity and low MIC
RESUMO
The current study was carried out on 50 patients with symptoms of acute pharyngotonsillitis. Throat swabs were inoculated on 5% sheep blood agar plates and incubated in various atmospheric conditions to estimate optimum isolation conditions of beta-hemolytic streptococci. Strict anaerobic conditions were superior for isolation of both group A and non-group A beta-hemolytic streptococci when compared to aerobic conditions, microaerophilic states induced by stabbing blood agar plates or to incubation in an atmosphere enriched with 5-10% CO2. Anaerobiosis was the most sensitive means of isolation of the clinically relevant group A strains. This high sensitivity was not coupled with high specificity as this method permitted the growth of non-group A strains. The use of bacitracin disk sensitivity test is a simple and sensitive to identify group A strains. The combination of the previous two means seems to be the best option to characterize group A beta-hemolytic streptococci