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The genes coding for 4 aminoglycoside-modifying enzymes AAC(6′)-APH(2″), APH(3′), ANT(4′) and ANT(6) were determined in 44 Slovak clinical isolates of Enterococcus faecalis with high-level resistance to gentamicin (HLGR, collection 1) and 48 E. faecalis isolates with resistance to amikacin (AR, collection 2). The occurrence of spotted genes was (collection 1 vs. collection 2): aac(6′)-aph(2″) 81.8 vs. 8.3 %, ant(4′) 52.3 vs. 81.3 %, aph(3′) 50 vs. 56.3 % and ant(6) 6.8 vs. 4.2 %, the most frequent combinations of genes in the HLGR collection were aac(6′)-aph(2″)+ant(4′) and aac(6′)-aph(2″)+aph(3′). In contrast, the aph(3′)+ant(4′) gene profile was predominant in AR isolates. None of the isolates contained all four AGME genes simultaneously. [ABSTRACT FROM AUTHOR]

Susceptibility of 75 clinical isolates of Enterobacteriaceae to 15 aminoglycosides, beta-lactams and fluoroquinolones was studied. The isolates originated from 3 wards (Pathological neonates, Surgical ICU, and Pediatric cardiology) of the Children's University Hospital in Bratislava, Slovakia. The isolates were collected from patients in April and November 1999 and June 2001. All isolates were resistant to gentamicin, tobramycin, and ampicillin. The majority of isolates were resistant to netilmicin, amikacin, cephalosporins, and azthreonam, but they were susceptible to meropenem and fluoroquinolones. The prevailing number of isolates produced 2 to 4 aminoglycoside-modifying enzymes. All isolates produced beta-lactamases and 80% produced extended-spectrum beta-lactamases (ESBL). Plasmid analysis revealed in the majority of isolates, originating from all 3 wards, a 116 kb plasmid throughout the entire period of study. Restriction analysis suggested a dissemination and persistence of a single nosocomial plasmid at all 3 units of the large pediatric hospital in Bratislava. [ABSTRACT FROM AUTHOR]

This study prospectively investigated all 157 cases of Acinetobacter baumannii bacteremia occurring in major university hospitals or tertiary care institutions in Slovakia during 1999 in order to determine the antimicrobial susceptibility, risk factors and outcome. Resistance to meropenem was 7.4, gentamicin 35.6, amikacin 26.5, cefepime 20.4 and ciprofloxacin 32.7%, but was only 17.3% to cefoperazone/sulbactam or ampicillin/sulbactam. Antimicrobial susceptibility of A. baumanii was lowest among isolates from cancer patients (ceftazidime 58%, piperacillin/tazobactam 52% and azthreonam 48%; p ≤ 0.01-0.001). In univariate analysis, several risk factors, such as wound infection (p ≤ 0.01) and ventilatory support (p ≤ 0.0001), were significantly related to A. baumannii bacteremia in surgical patients. Neutropenia (p ≤ 0.0001), antineoplastic chemotherapy (p ≤ 0.0001) and prior antibiotic therapy (p ≤ 0.0006) were significant risk factors for A. baumannii bacteremia in cancer patients. In addition, ventilatory support and surgery (p ≤ 0.0001) and prior antibiotic therapy (p ≤ 0.01) were significantly related to A. baumannii bacteremia in children. Colonization at other body sites (p ≤ 0.05), diabetes mellitus (p ≤ 0.04) and decubital ulcers/burns (p ≤ 0.002) as underlying disease were significantly related to death due to A. baumannii bacteremia. In a multiple logistic regression model, decubital ulcers/burns as underlying disease (p ≤ 0.0006; relative risk 5.08) and nosocomial pneumonia (p ≤ 0.045; relative risk 5.08) were independent predictors of mortality. Mortality was similar between cancer and surgical patients but significantly lower in children vs. adults (p ≤ 0.009). [ABSTRACT FROM AUTHOR]

Occurrence and transferability of β-lactam resistance in 30 multi-resistant Escherichia coli, Klebsiella spp., Enterobacter spp., Pantoea agglomerans, Citrobacter freundii and Serratia marcescens strains isolated from children between 0 and 3 years of age is presented. The strains were resistant to ampicillin (30), cefoxitin (22), cefotaxime (30), ceftriaxone (30), ceftazidime (30) and aztreonam (28), but susceptible to cefepime (30) and imipenem (26). Twenty-eight of 30 isolates possessed a transferable resistance confirmed by conjugation and isolation of 79–89-kb plasmids. The β-lactam resistance was due to production of β-lactamases and ceftazidime proved to be stronger β-lactamase inductor than ceftriaxone. Twenty-five clinical isolates expressed transferable extended spectrum β-lactamases, and chromosomally encoded AmpC β-lactamase. [ABSTRACT FROM AUTHOR]

Introduction: Melanized or dematiaceous fungi are associated with a wide variety of infectious syndromes. Cladophialophora bantiana is one of the most common and dangerous neurotropic fungi, able to cause brain abscess and disseminated infection., Case Presentation: We report a new case of phaeohyphomycosis brain abscesses caused by C. bantiana in Slovakia. The patient was a 63-year-old man having undergone heart transplantation, with dyspnoea, left-sided bronchopneumonia and fevers. CT (computed tomography) and MRI (magnetic resonance imaging) of the brain revealed numerous abscesses. Bacterial infection was proven by neither the growth of bacteria in culture nor the presence of bacterial antigens. Direct microscopy of the pus from the brain abscess showed Gram-positive hyphae. The isolate was finally identified as C. bantiana based on morphological and physiological features, and on DNA sequence analysis., Conclusion: In spite of appropriate therapy, neurological complications and accelerated respiratory insufficiency resulted in the patient's death. Concerning clinical manifestation of the brain phaeohyphomycosis that can sometimes be a problem to distinguish from malignancy, physicians should also assume infection caused by this serious pathogen.

A case report of ventriculoperitoneal shunt infection caused by Candida lusitaniae in a 6-year-old patient with cerebral astrocytoma and obstructive hydrocephalus is presented briefly with emphasis on the course of antifungal treatment. Seven isolates recovered subsequently from the cerebrospinal fluid were studied retrospectively. To confirm identity, isolates were typed using pulsed-field gel electrophoresis and melting curve of random amplified polymorphic DNA (McRAPD). Further, the ability to form biofilm and its susceptibility to systemic antifungals were evaluated. Using McRAPD, identity of C. lusitaniae isolates showing slight microevolutionary changes in karyotypes was undoubtedly confirmed; successful application of numerical interpretation of McRAPD for typing is demonstrated here for the first time. The strain was also recognized as a strong biofilm producer. Moreover, minimum biofilm inhibitory concentrations were very high, in contrast to low antifungal minimum inhibitory concentrations of isolates. It can be concluded that McRAPD seems to be a simple and reliable method not only for identification but also for typing of yeasts. A ventriculoperitoneal shunt colonized by C. lusitaniae was revealed as the source of this nosocomial infection, and the ability of the strain to form biofilm on its surface likely caused treatment failure.

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.

Objective: A multicenter study was conducted to obtain "in vitro" chloramphenicol and colistin susceptibility data on multiresistant hospital bacterial pathogens in Slovak Republic., Material and Methods: During the period of April-June 2001, 628 clinical bacterial multiresistant isolates from patients with serious infections were selected in 10 hospitals and tested to a large scale of antibiotics by means of a microdilution method. The strains expressed either a significant resistance phenotype (ESBL, MRSA, CoNMRS, MLSB/c, efflux in Ps. aeruginosa), or were resistant to one or more preparations in at least half of reliable unrelated antibiotic groups (beta-lactams, aminoglycosides, quinolons, macrolides)., Results: Both chloramphenicol and colistin retained significant "in vitro" activity against many multiresistant hospital bacterial pathogens. The highest activity of chloramphenicol was documented for isolates of Stenotrophomonas maltophilia (76,5 % susceptible, MIC50 = 4 mg/L, MIC90 = 16 mg/L) and of Staphylococcus aureus (76,2 % susceptible, MIC50 = 8 mg/L, MIC90 = 16 mg/L). In tested Pseudomonas aeruginosa (82,5 % susceptible, MIC50 = 2 mg/L, MIC90 = 16 mg/L) and Stenotrophomonas maltophilia (88,2 % susceptible, MIC50 = 1 mg/L, MIC90 = 8 mg/L) isolates colistin represented the most "in vitro" effective antibiotic. Colistin was the only "in vitro" effective antimicrobial in four of 120 multiresistant Pseudomonas aeruginosa isolates tested in our study., Conclusions: The study confirmed a good "in vitro" susceptibility of many multiresistant hospital bacterial pathogens to chloramphenicol and colistin in Slovak Republic. The clinical application of chloramphenicol and colistin might be reconsidered in infections caused by extremely resistant bacteria with prooved susceptibility to these antibiotics. It is important to consider, that the infection danger has to exceed the risk of antibiotic toxicity.

Among 413 strains of S. aureus isolated from patients with chronic staphylococcal infections, from haemocultures in bacteriaemia and septic conditions, from gynaecological materials and nasal plugs of healthy carriers the authors detected the production of one or several types of enterotoxins in 124 strains (30.0%), production of TSST-1 in 19 strains (4.6%) and the concurrent production of enterotoxins and TSST-1 in 38 strains (9.2%). The highest ratio of toxigenic strains of S. aureus was found in departments (51.4%) and from hospitalized patients in blood cultures in bacteriaemias and septic conditions (41.2%). In a group of 184 strains from patients with chronic staphylococcal infection toxin production was proved in 49 strains (26.6%). Of 74 strains of S. aureus isolated from healthy carriers there were 16 toxigenic strains (21.6%). The most frequent type of enterotoxins were enterotoxins type A (26.7%) and C (24.4%). 21 strains (24.4%) produced more than one type of enterotoxins.

A total of 201 cases of fungaemia in children in a 12-year national survey from seven University Paediatric Clinics in Slovakia in 1990-2001 was assessed to determine risk factors, therapy and outcome, and to compare those cases with fungaemia in 130 adult cancer patients studied in a similar survey. Four univariate analyses were performed to assess differences in aetiology, antifungal susceptibility and outcome between fungaemia in neonates and paediatric intensive care unit (ICU) patients as well as between paediatric and adult cancer patients with fungaemia. There was a significant difference in aetiology and antifungal susceptibility between the subgroups of children with fungaemia: 83.3% of neonates versus 40.2% in children with cancer were due to Candida albicans. None of the non-albicans Candida spp. (NAC) in neonates but 23.5% of NAC isolates from children with cancer were resistant to fluconazole. C. albicans caused 144 (71.1%) episodes and NAC 48 (23.7%) episodes. Trichosporon beigelii, Blastoschizomyces (Trichosporon) capitatus, Rhodotorula rubra and Cryptococcus laurentii were found less frequently in neonates than in children with cancer (18.8%). There were not many differences in risk factors between paediatric fungaemia and adult cancer fungaemia except C. albicans aetiology, corticosteroid use in therapy, breakthrough fungaemia after ketoconazole prophylaxis and meningitis as a complication, which were observed significantly more frequently among children than in adults, both with cancer and fungaemia. Thirty-three of the paediatric fungaemias were breakthrough cases and appeared frequently in children with cancer. Fifty-one (25.1%) children died with fungaemia (attributable mortality) and 25 (12.7%) due to underlying disease with fungaemia; overall mortality was 37.8% and there was no significant difference in death rates between the subgroups of paediatric patients (neonates, children in ICUs and children with cancer).

224 coagulase-negative strains of staphylococci (CNS) isolated from haemocultures of hospitalized patients were classified into 11 types. The most frequent one was S. epidermis (73.2%), S. haemolyticus (7.6%), S. lugdunensis (6.7%) and S. hominis (3.6%). In different strains virulence factors were assessed: production of mucus and delta toxin. Based on these properties the strains were classified into biotypes. Of 164 strains of S. epidermis mucus was produced by 64.6% and delta toxin by 75.0%. Of 17 strains of S. haemolyticus mucus was produced by 8 and delta toxin by 10 strains. Of 15 strains of S. lugdunensis 9 strains produced both virulence factors. Of 8 strains of S. hominis 5 strains produced mucus and 3 delta toxin. In strains S. capitis, S. sciuri, S. auricularis, S. caprae these factors were not detected. The most frequent biotypes were: subtype 3 (43.3%), 1a (26.8%) and 1b (10.3%). The sensitivity of CNS to 11 antibacterial substances was assessed quantitatively by estimating the MIC (mg/l). The most effective antibiotic was vancomycin (100%) and tetracycline (76.8%). Only 26.3% strains were sensitive to oxacillin and cefalotine. Of 224 CNS (70%) were resistant to more than 8 antibacterial substances.

The objective of this study was to assess risk factors and the outcome of breakthrough fungaemias (BFs) occurring during fluconazole (FLU) therapy in non-cancer and non-HIV individuals. Thirty-three fungaemias occurring during therapy with FLU among a total of 310 fungaemias observed within a 10-y national survey were analysed. The agar disk diffusion method was used for antifungal susceptibility testing and the Vitek system for species identification. Univariate and multivariate analysis was performed to determine risk factors for BF. All BFs were due to species known to be susceptible to FLU: Candida albicans (25/33), C. parapsilosis (6/33) and C. guillermondii (2/33). The mean number of positive blood cultures per episode was 2.4. The MIC of Candida spp. to FLU was 0.5-8 mg/ml (all strains were susceptible in vitro). Neonatal age (< 4 weeks), very low birth weight, prior surgery, central venous catheter placement, artificial ventilation, total parenteral nutrition and C. parapsilosis were significantly related to BF in univariate analysis, but only central venous catheter placement was significantly related in multivariate analysis. However, the outcome of BFs and non-BFs was similar. All BFs occurred in non-HIV patients who were not previously treated with azoles, and were caused by in vitro FLU-susceptible species (C. albicans and C. tropicalis). Thus factors other than in vitro susceptibility play a role in BFs.

The transferability and expression of beta-lactam resistance were compared in multiresistant clinical isolates of Enterobacter spp. collected from different hospitals in Bratislava, Slovakia (n = 15) and Innsbruck, Austria (n = 19) during 1996-1997. The strains from Bratislava were resistant to ampicillin, cefoxitin, cefotaxime, ceftazidime and ceftriaxone. All strains from Innsbruck were resistant to ampicillin and cefoxitin; 17 were also resistant to ceftazidime and aztreonam but the majority remained susceptible to cefotaxime and ceftriaxone. All strains were susceptible to cefepime and imipenem. The majority of the tested strains transferred resistance determinants to E. coli recipient by conjugation. Production of beta-lactamase including ESBL was the major mechanism of beta-lactam resistance. Large plasmids of 77-88 and 91 kb were confirmed in clinical isolates from Bratislava and Innsbruck.

The authors demonstrated the transferability of antibiotic resistance genes in nosocomial strains of Klebsiella pneumoniae, isolated from newborn children at the Paediatric University Hospital in Bratislava. Strains were resistant to cefotaxime, ceftazidime and aztreonam. The determinants of resistance (carbenicillin, cephaloridine, cefotaxime, ceftazidime and aztreonam) were transferred to recipient strains of Escherichia coli K-12 and Proteus mirabilis P-38. The transfer of resistance determinant from donor strains was demonstrated by the analysis of the resistance spectrum in transconjugant clones of recipient strains by the method of indirect selection. The ability of production of extended spectrum beta-lactamases (ESBL) was demonstrated by the double disc diffusion test. Synergy between clavulanate and cefotaxime, clavulanate and ceftazidime and/or clavulanate and aztreonam indicated production of ESBL by these strains.

Three cases of Clavispora lusitaniae invasive fungal infections are reported. All three infections appeared in cancer patients presented with fungaemia, one additionally with meningitis. Two of them were breakthrough -- they developed during therapy with conventional amphotericin B with a dose of 0.5 mg kg(-1) day(-1) . All three were cured: two with intravenous fluconazol and one with an increasing dose (1 mg kg(-1) day(-1)) of amphotericin B. In one of two breakthrough cases the sensitivity of the strain to antifungals was tested against antifungal agents and showed in vitro resistance to amphotericin B (MIC 2 eta g ml(-1)).