Clostridium difficile-associated diarrhea in the Clinical Center of Vojvodina, Serbia, in the period 2008 to 2012

Clostridium difficile-associated diarrhea (CDAD) has been recognized as the leading cause of diarrhea worldwide. In the last five years, it has become the leading cause of diarrhea in the Clinical Center of Vojvodina (CCV) as well. The aim of this study was to determine the epidemiology and total cost of treatment for all patients with Clostridium difficile-associated diarrhea hospitalized at the Infectious Disease Clinic of the CCV; to analyze the costs of treatment with regard to therapeutic approach; to compare the costs of treatment in each year of the investigated period related to the number of patients, and to analyze the outcome of treatment. The study was retrospective, and the data were collected from the medical records of 472 patients with Clostridium difficile diarrhea treated from 2008 to 2012 and analyzed. Of the total 472 patients with CDAD, 54.23% were female and the average age was 65.84. A statistically significant majority of them had been previously treated in other hospitals and a minority in ambulatory settings (395 inpatients vs. 77 outpatients, p=0.000, p<0.05). Of the 395 previously hospitalized patients, most were from the Clinic of Urology of the CCV (58, 14.68%). When comparing therapeutic options, oral vancomycin was significantly more frequently used than other protocols. The average mortality rate during the study period was 6.51%. In this period, total hospital costs related to Clostridium difficile diarrhea in the Infectious Disease Clinic were $636,679.92. Implementation of infection-control measures and a restricted use of antibiotics would result in a great reduction in material costs

Susceptibility to antifungal agents of Candida spp. from blood and feces collected in Novi Sad in 3-year period (2008-2010)

Candidemia is an important emerging nosocomial infection in patients with risk factors. Candida species from nonsterile sites can give insight into the characteristics of strains that may cause invasive disease. The aim of this study was to evaluate antifungal susceptibility of Candida blood and fecal isolates in Novi Sad, Vojvodina. During a 3-year period (2008 to 2010), 424 isolates of Candida spp. were collected, 30 bloodstream isolates and 394 strains from fecal samples. In vitro susceptibility of these isolates to five antifungal agents was established using commercial ATB FUNGUS 3 (Bio-Mérieux). Predominant species was Candida albicans (6 isolates from blood and 269 from feces). Resistance to one or more antifungal agents was less common in Candida albicans (3.63%) than in other species (24.83%). Resistance to itraconazole was the most commonly found in both groups of isolates, 9.64% strains from feces and 20% from blood samples. Twelve isolates were multiply resistant, usually to fluconazole, itraconazole, and voriconazole. Resistance to amphotericine B was extremely rare. Although resistance to antimycotics of Candida spp. is rare at present, continued surveillance of antifungal susceptibility is necessary in order to monitor trends, and to choose the right empiric therapy

Sphingomonas paucimobilis as a biofilm producer

The aim of this study was, for the first time in our country, to identify the capability of isolates of Sphingomonas paucimobilis to form a biofilm. In the 3-month period from January 1st to March 31st 2010, a total of 2630 samples of drinking water were microbiologically examined in the Institute of Public Health of Vojvodina, Serbia. From all examined samples of drinking water, non-fermentative Gram-negative oxidase positive bacilli were identified in 113 samples (4.30%). The bacteria isolates were identified as Sphingomonas paucimobilis (4 isolates), based on analysis by the automated VITEK 2 Compact system; biofilm formation was examined according to the modified method of Stepanović et al. (2000). All 4 Sphingomonas paucimobilis strains tested showed a strong biofilm-producing ability. Considering the potential pathogenic features of Sphingomonas paucimobilis, the presence of these strains in drinking water distribution systems is not desirable. Therefore, adequate biofilm degradation and management of drinking-water distribution networks that will guarantee microbiologically safe drinking water is recommended

Prevalence of quinolone resistance and mutations in the topoisomerase genes in Salmonella enterica serotype Enteritidis isolates from Serbia

The prevalence of quinolone resistance was studied in Salmonella enterica serotype Enteritidis isolates collected during 2005-2010 in Southern Ba. cka County, Serbia. A total of 878 clinical isolates were examined, among which 19 (2.2%) nalidixic acid (NAL)-resistant S. Enteritidis were detected by selection on agar plates containing 64 mg/L NAL. Antimicrobial susceptibility of the isolates was tested by the agar dilution method. According to Clinical and Laboratory Standards Institute (CLSI) breakpoints, ciprofloxacin (CIP) resistance was not present in the strains. Multiple drug resistance was rare, and resistance to NAL was most often present as a single resistance property. All but one NAL-resistant S. Enteritidis showed reduced susceptibility to CIP [i.e. minimum inhibitory concentration (MIC) gt = 0.125 mg/L]. This isolate of human origin had a CIP MIC of 0.064 mg/L and DNA sequencing revealed that it contained an Asp87Gly gyrA mutation. Most of the remaining isolates had MICs for NAL and CIP of 256 mg/L and 0.256 mg/L, respectively. Mutations in the Asp87 codon resulted in substitutions to Asn in most of the isolates, but Asp87Gly and Ser83Phe exchanges were also detected. No mutations were present in the gyrB, parC or parE genes. Although CIP resistance was absent, reduced susceptibility characterised by mutations in gyrA was apparent among S. Enteritidis isolates from Serbia

Mechanisms of quinolone resistance and implications for human and animal health

Quinolone antibiotics have been widely used in human and veterinary medicine. This has caused the development of resistance and difficulties in the treatment of complicated bacterial infections in humans. The resistance to quinolones develops due to chromosome mutations and it can also be transferred by plasmids. The target enzyme for quinolones in Gram-negative bacteria is Gyrasa A, while the target enzyme in Grampositive bacteria is mostly topoisomerase IV. Gyrase A consists of two subunits encoded by genes gyrA and gyrB. The function of the enzyme is to introduce negative super coiling in DNA and therefore is essential for the replication of bacteria. Quinolone resistance develops if point mutations at 83 and/or 87 codon are introduced on gyrA. Establishing a minimal inhibitory concentration (MIC) to this group of antimicrobials will reveal possible mutations. Recently it was discovered that quinolone resistance is transmittable by plasmid termed PMQR (plasmid mediated quinolone resistance). The target gene marked qnr encodes a pentapeptide repeat family protein. Pentapeptide repeats form sheets, involved in protein-protein interactions. Qnr protein binds to GyrA protecting the enzyme from the inhibitory effect of ciprofloxacin. The distribution of qnr related resistance is higher in humans than in animals. In poultry, however, this type of resistance is present more than in other animals. Plasmid mediated resistance contributes to the faster spread of quinolone resistance. Proper food handling will significantly contribute to decreasing the risk from infection to which people are exposed. In medical and veterinary laboratories antimicrobial resistance monitoring in clinical and environmental isolates is advised. Since correlation between antibiotics application and antimicrobial resistance is often suggested, antimicrobial use must be under strict control of the authorities both in human and in veterinary medicine.

Listeria monocytogenes isolated in ready-to-eat food in South Bačka region of Vojvodina province, Serbia

Listeria monocytogenes is pathogenic bacterium that can contaminate food products during and after processing. As ready-to-eat food does not undergo any treatment to ensure its safety before consumption, the risk of foodborne disease must be considered if this pathogen is present in the food. As diseases caused by contaminated food are an important public health problem today, the aim of this study was to determine the prevalence of Listeria monocytogenes in different ready-to-eat food products. In the seven-month period from June 1 to December 31, 2011, a total of 1 380 food samples were examined in the Division of Sanitary Bacteriology, Center for Microbiology, Institute of Public Health of Vojvodina in Novi Sad. A total of 912 samples were analyzed for the presence of Listeria monocytogenes according to ISO 11290-2. The identity of suspected Listeria monocytogenes was confirmed using the VITEK 2 Compact system (BioMerieux, France). Out of 912 samples, Listeria monocytogenes was detected in 18 (1.97%). Listeria monocytogenes was mostly found in cooked meals (in 6 samples out of 18), sandwiches (4 samples) and frozen food, such as ice-cream and frozen vegetables (4 samples). It was also found in tofu bread spreads (2 samples), cream cheese (1 sample) and cakes (1 sample). The presence of Listeria monocytogenes in some ready-to-eat food could present a public health hazard, particularly to the high-risk population group, because of the high mortality rate associated with listeriosis and the widespread nature of the organism. Monitoring of listeriosis is essential to prevent foodborne outbreaks, and in assessing human health risk in ready-to-eat foods