Staphylococcal biofilm on wedding rings worn by laboratory workers.

Hands of healthcare workers play essential role in the spreading of antimicrobial-resistant microorganisms in and out of the healthcare settings. Less is known about the role of laboratory workers (LWs). The aim of our study was to evaluate the presence of biofilm-forming staphylococci on the surface of jewelry rings of LWs and their antimicrobial susceptibility pattern.A total of 79 LWs from eight different microbiology laboratories that process and analyze specimens from the tertiary care hospitals in Belgrade, Serbia participated in the study. The study was reviewed and approved by the institutional review boards at hospitals. Samples were taken after hand washing. Bacteria on LWs wedding rings were detected with the rolling method, and further analyzed in order to determine the number of colony forming unit (CFU) per ring, species of bacteria and their antimicrobial susceptibility pattern, methicillin resistance and biofilm-producing capacity in vitro.Staphylococci were recovered from 60.8% of wedding rings. All strains produced biofilm (25% weak, 56.2% moderate and 18.8% large amount), with significant difference between species (P < 0.001). Staphylococcus aureus and Staphylococcus epidermidis formed the largest amount of biofilm and had the largest number of CFU per ring. Staphylococci were most commonly resistant to penicillin (66.7%), tetracycline (50.0%), and erythromycin (45.8%); 41.7% of isolates was multidrug resistant and mecA gene was detected in five strains. All strains were susceptible to linezolid, vancomycin, teicoplanin and tigecycline.Staphylococci colonize LWs wedding rings, form biofilm on it, have multidrug resistant phenotype and/or carry mecA gene, representing a significant reservoir for the spreading of microorganisms and resistance. As far as we know, our study is the first that address this topic in laboratory workers.

Ralstonia pickettii bacteremia in a cardiac surgery patient in Belgrade, Serbia.

Ralstonia pickettii is an opportunistic bacterium found in the water environment with an increasing incidence as a nosocomial pathogen. The objectives of this study were to describe R. pickettii bacteremia in a cardiac surgery patient and to evaluate its ability to grow in a saline solution and to form biofilm. The patient in this study underwent mitral and aortic valve replacement surgery with two aortocoronary bypasses. She developed signs of respiratory and renal failure, therefore hemodialysis was started. After 25 days in an intensive care unit, the patient had recurrent episodes of fever with signs of bacteremia. R. pickettii was identified from blood cultures by MALDI-TOF MS. Antimicrobial susceptibility testing was performed using disc diffusion and broth microdilution methods in accordance with EUCAST methodology and results were interpreted following clinical breakpoints for Pseudomonas spp. The isolate was susceptible to all tested antimicrobial agents except aminoglycosides and colistin. Survival of R. pickettii was analyzed in saline solution with four different starting concentrations at 25 °C and 37 °C for six days. Biofilm capacity was tested using the microtiter plate method. R. pickettii showed substantial growth in saline solution, with starting concentration of 2 CFU ml-1 reaching 107 CFU ml-1 after six days. There was no significant difference between growth at 25 °C and 37 °C. This indicates that storage of contaminated solutions at room temperature can enhance the count of R. pickettii. Our strain did not show the capacity to form biofilm. The patient responded well to adequate treatment with ceftazidime, and after 48 days in ICU she was discharged to convalesce.

The Effect of Vacuum-Assisted Closure Therapy on Methicillin-Resistant Staphylococcus aureus Wound Biofilms.

Biofilm-associated wound infections are a major global health issue, and methicillin-resistant Staphylococcus aureus (MRSA) is among the greatest therapeutic challenges. Vacuum-assisted closure (VAC) therapy is now being revisited as an alternative treatment for both acute and chronic wounds. However, data supporting the concept of its antibiofilm effect remain limited. Using quantitative biofilm-forming assay and a range of genotypic methods (spa, SCCmec, and agr typing), study authors showed that VAC therapy can significantly prevent biofilm formation (P < .01) of a range of MRSA wound isolates differing widely in their biofilm-forming abilities and genetic background. The best effect was presented on CC5-MRSA-SCCmecI-agrII, a dominant MRSA clone among wound isolates worldwide. An assessment of effects of different protocols on dressing changes (1 or 2 times per week) demonstrated significantly greater antibiofilm activity (P < .05) of 3-day dressing changes. These findings support the use of VAC therapy as a topical antibiofilm treatment for the effective management of wound healing.

Increased Serum Interleukin-10 but not Interleukin-4 Level in Children with Mycoplasma pneumoniae Pneumonia.

Background: Mycoplasma pneumoniae (MP) is a common cause of community-acquired pneumonia in children, and it has been associated with wheezing. The aim of this study was to examine the serum level of interleukin (IL)-4 and IL-10 in children with Mycoplasma pneumoniae pneumonia (MPP) and to analyse them in relation to the presence of wheezing. Methods: The study included 166 children with radiologically confirmed pneumonia. MP infection was confirmed by enzyme-linked immunosorbent assay (ELISA) serum MP-IgM and MP-IgG test and throat swab MP DNA with real-time polymerase chain reaction. Serum levels of IL-4 and IL-10 were measured using ELISA. Results: There was no significant difference in serum level of IL-4 between children with MPP and those with non-MPP. Among children with MPP, we found similar level of IL-4 regardless of the personal and family history of allergy and asthma or the presence of wheezing. A significantly higher level of IL-10 was found in children with MPP than in children with non-MPP (32.92±18.582 vs. 27.01±14.100 pg/ml, p =0.022). Furthermore, wheezing children with MPP had a significantly higher level of IL-10 than children with MPP without wheezing (43.75±26.644 vs. 27.50±10.211 pg/ml, p=0.027). Conclusion: Our results show significantly increased serum level of IL-10 in children with MPP, which was significantly higher in children with wheezing. These findings may suggest a role of IL-10 in the pathogenesis of MPP and in the occurrence of wheezing during acute MP infection.

Licheniocin 50.2 and Bacteriocins from Lactococcus lactis subsp. lactis biovar. diacetylactis BGBU1-4 Inhibit Biofilms of Coagulase Negative Staphylococci and Listeria monocytogenes Clinical Isolates.

BACKGROUND: Coagulase negative staphylococci (CoNS) and Listeria monocytogenes have important roles in pathogenesis of various genital tract infections and fatal foetomaternal infections, respectively. The aim of our study was to investigate the inhibitory effects of two novel bacteriocins on biofilms of CoNS and L. monocytogenes genital isolates. METHODS: The effects of licheniocin 50.2 from Bacillus licheniformis VPS50.2 and crude extract of bacteriocins produced by Lactococcus lactis subsp. lactis biovar. diacetylactis BGBU1-4 (BGBU1-4 crude extract) were evaluated on biofilm formation and formed biofilms of eight CoNS (four S. epidermidis, two S. hominis, one S. lugdunensis and one S. haemolyticus) and 12 L. monocytogenes genital isolates. RESULTS: Licheniocin 50.2 and BGBU1-4 crude extract inhibited the growth of both CoNS and L. monocytogenes isolates, with MIC values in the range between 200-400 AU/ml for licheniocin 50.2 and 400-3200 AU/ml for BGBU1-4 crude extract. Subinhibitory concentrations (1/2 × and 1/4 × MIC) of licheniocin 50.2 inhibited biofilm formation by all CoNS isolates (p < 0.05, respectively), while BGBU1-4 crude extract inhibited biofilm formation by all L. monocytogenes isolates (p < 0.01 and p < 0.05, respectively). Both bacteriocins in concentrations of 100 AU/mL and 200 AU/mL reduced the amount of 24 h old CoNS and L. monocytogenes biofilms (p < 0.05, p < 0.01, p < 0.001). CONCLUSIONS: This study suggests that novel bacteriocins have potential to be used for genital application, to prevent biofilm formation and/or to eradicate formed biofilms, and consequently reduce genital and neonatal infections by CoNS and L. monocytogenes.

Quantification of biofilm formation on silicone intranasal splints: An in vitro study.

OBJECTIVES: Biofilms are associated with persistent infections and resistant to conventional therapeutic strategies. The aim of this study was to investigate the quantity of biofilm produced on silicone intranasal splints. METHODS: Quantity of biofilm formation on silicone splints (SS) was tested on 15 strains of Staphylococcus aureus and Moraxella catarrhalis, respectively. Antimicrobial susceptibility testing was performed in accordance with European Committee on Antimicrobial Susceptibility Testing recommendations. RESULTS: All tested strains formed different amounts of biofilm on SS: 66.7% S. aureus and 93.3% M. catarrhalis were weak biofilm producers and 33.3% S. aureus and 6.7% M. catarrhalis were moderate biofilm producers. S. aureus formed significantly higher quantity of biofilm compared with M. catarrhalis (p < 0.05). Multidrug resistant S. aureus produced significantly higher amount of biofilm compared with non-multidrug resistant strains (p < 0.05). CONCLUSION: Quantity of biofilm on SS is highly dependent on bacterial species and their resistance patterns. Future studies are needed to ascertain another therapeutic option for prophylaxis prior to SS placement.

Mycoplasma pneumoniae as a causative agent of community-acquired pneumonia in children: clinical features and laboratory diagnosis.

BACKGROUND: Mycoplasma pneumoniae is a common cause of community-acquired pneumonia (CAP) in children. The aim of this study was to assess the prevalence of Mycoplasma pneumoniae infection in children with CAP and find clinical, radiological and laboratory features helpful to diagnose Mycoplasma pneumoniae pneumonia. Furthermore, we evaluated the value of serology, real-time PCR (RT-PCR) and culture for the accurate diagnosis of Mycoplasma pneumoniae pneumonia. METHODS: The study included 166 children aged between 1 and 15 years with radiologically confirmed pneumonia. Throat swab specimens were cultured and assessed by RT-PCR for the presence of Mycoplasma pneumoniae. Mycoplasma pneumoniae-specific IgM and IgG antibodies were determined using ELISA in paired sera. RESULTS: Mycoplasma pneumoniae pneumonia was diagnosed in 14.5% CAP cases. Cough (p=0.029), headache (p=0.001) and wheezing (p=0.036) were more frequent in children with Mycoplasma pneumoniae pneumonia compared to children with pneumonia caused by other pathogens. Logistic regression analysis showed that headache (odds ratio [OR] =36.077, p=0.001) and wheezing (OR=5.681, p=0.003) were significantly associated with MP pneumonia. Neither radiological findings, nor common laboratory parameters distinguished Mycoplasma pneumoniae infection in children with CAP. Using IgG serology in paired sera as the gold standard, we found that sensitivity of IgM serology, RT-PCR and culture was equal (81.82%), while specificity values were 100%, 98.6% and 100% respectively. We observed that combination of IgM detection in acute-phase serum and RT-PCR was positive for 91.7% of cases with Mycoplasma pneumoniae infection. CONCLUSIONS: There are no characteristic radiological findings, or routine laboratory tests that would distinguish CAP caused by Mycoplasma pneumoniae from other CAP. It was found that clinical features such as headache and wheezing are indicative for Mycoplasma pneumoniae infection. Furthermore, it was found that during the acute phase of disease, detection of IgM antibodies in combination with RT-PCR allows for precise and reliable diagnosis of Mycoplasma pneumoniae infections in children.

[Phenotypic detection of beta-lactamases production in Enterobacteriaceae].

INTRODUCTION: Beta-lactam antibiotics are the most commonly used antibacterial drugs. However, many bacteria have developed resistance to these antibiotics, and the most common form of resistance is the production of beta-lactamase enzymes. Many members of the Enterobacteriaceae family produce different types of these enzymes. OBJECTIVE: The aim of this study was to perform phenotypic detection of production and identification of beta-lactamase type in Enterobacteriaceae isolated from different clinical specimens from patients hospitalized in the Clinical Center of Serbia. METHODS: The strains of Enterobacteriaceae were collected between November 2011 and January 2012 in the laboratory of the Clinical Center of Serbia.The isolates were identified according to the standard microbiology procedures and confirmed by the Vitek2 automated system. Antimicrobial susceptibility testing was performed by the disk diffusion method, and the phenotypic detection of production and identification of beta-lactamases was performed according to previously described methodologies. RESULTS: In this study, a total of 172 Enterobacteriaceae strains were isolated. Further testing was performed on 54/145 (37.2%) strains showing decreased susceptibility to beta-lactam antibiotics: 13/85 (15.3%) Escherichia coli, 31/46 (67.4%) Klebsiella pneumoniae and 10/14 (71.4%) Proteus mirabilis. Among them, 40/145 (27.6%) strains produced extended spectrum beta-lactamases (ESBLs), 9/145 (6.2%)--AmpC, 1/145 (0.7%)--K1 beta-lactamase and 4/145 (2.8%)--carbapenemases. Carbapenemases were predominantly detected in K. pneumoniae (75%). CONCLUSION: Enterobacteriaceae produce different types of beta-lactamases, and the most common type in our study was ESBLs. Production of carbapenemases detected in Enterobacteriaceae is also an associated problem.

[Examination of possible role of the chlamydial stress proteins in pathogenesis of ectopic pregnancy].

INTRODUCTION: Chlamydia trachomatis infections are the most prevalent bacterial sexually transmitted infections recognized throughout the world. In the last few years, several studies have indicated that predisposition of C. trachomatis to persist within the host cell is recognized as a major factor in the pathogenesis of chlamydial infection. During persistent chlamydial infection, the stress protein hsp60 is synthesized continually as immunopathologic antigen. Antibodies to hsp60 are found in women with tubal occlusion, but these antibodies are not detected in women with the acute C. trachomatis infection, which indicates that hsp60 has an important role in pathogenesis of persistant chlamydial infection. OBJECTIVE: The aim of this study was to determine the role of chlamydial stress proteins (heat shock proteins) in pathogenesis of ectopic pregnancy. METHODS: The study included 40 women with ectopic pregnancy (experimental group) and 34 women with normal pregnancy (control group). C. trachomatis was detected in endocervical smears by direct immunofluorescence test, while specific antibodies against Chlamydia spp. and against hsp60 were detected by ELISA. RESULTS: DIF method detected the presence of C. trachomatis in 12.5% of women with the ectopic pregnancy and 17.6% of women with normal pregnancy. IgG antibodies against Chlamydia spp. were found in 57.5% of women with the ectopic pregnancy and 26.5% of women with normal pregnancy. IgA antibodies were positive in 37.5% of women with the ectopic pregnancy and 2.9% of women with normal pregnancy. IgG antibodies against hsp60 were positive in 37.5% of women with the ectopic pregnancy and 14.7% of women with normal pregnancy. CONCLUSION: The results of this study have proven the correlation between the ectopic pregnancy and the presence of IgG antibodies to chlamydial hsp60.

[Diagnosis of bacterial vaginosis].

Bacterial vaginosis is a common, complex clinical syndrome characterized by alterations in the normal vaginal flora. When symptomatic, it is associated with a malodorous vaginal discharge and on occasion vaginal burning or itching. Under normal conditions, lactobacilli constitute 95% of the bacteria in the vagina. Bacterial vaginosis is associated with severe reduction or absence of the normal H2O2-producing lactobacilli and overgrowth of anaerobic bacteria and Gardnerella vaginalis, Atopobium vaginae, Mycoplasma hominis and Mobiluncus species. Most types of infectious disease are diagnosed by culture, by isolating an antigen or RNA/DNA from the microbe, or by serodiagnosis to determine the presence of antibodies to the microbe. Therefore, demonstration of the presence of an infectious agent is often a necessary criterion for the diagnosis of the disease. This is not the case for bacterial vaginosis, since the ultimate cause of the disease is not yet known. There are a variety of methods for the diagnosis of bacterial vaginosis but no method can at present be regarded as the best. Diagnosing bacterial vaginosis has long been based on the clinical criteria of Amsel, whereby three of four defined criteria must be satisfied. Nugent's scoring system has been further developed and includes validation of the categories of observable bacteria structures. Up-to-date molecular tests are introduced, and better understanding of vaginal microbiome, a clear definition for bacterial vaginosis, and short-term and long-term fluctuations in vaginal microflora will help to better define molecular tests within the broader clinical context.

Nijmegen breakage syndrome and chronic polyarthritis.

We report on pediatric patient with Nijmegen breakage syndrome (NBS), a rare DNA repair disorder characterized by microcephaly, immunodeficiency and predisposition to malignant lymphomas, who developed juvenile idiopathic arthritis (JIA)-like polyarthritis. In patients with primary immunodeficiencies (PID), septic arthritis due to pyogenic bacteria or mycoplasmal arthritis are the most common osteoarticular manifestations. In certain PID, chronic, non-infectious arthritis resembling rheumatoid arthritis may occur. In our patient microbiologic cultures of synovial fluid including Mycoplasma spp. were negative. At first, because of suspected mycoplasmal arthritis we used macrolides and doxycycline combined with hydroxychloroquine but without therapeutic response. However, the use of rituximab led to remission of her polyarthritis lasting for 9 months. Autoimmune features were rarely reported in NBS. An occurrence of JIA-like, chronic polyarthritis in NBS, a DNA repair disorder characterized by decreased tolerance of immunosuppressive drugs such as methotrexate and a high natural risk for lymphomas, makes therapeutic approach even more complex.

[Nasal carriage of methicillin-resistant Staphylococcus aureus among medical students of Belgrade University].

INTRODUCTION: Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) present the growing problem in the whole world. Carriage of MRSA is most frequent in the nose, and medical students come in contact both with patients and different persons in the community. Therefore, they may be significant for the transmission of MRSA from hospitals to out-of-hospital communities and vice versa. OBJECTIVE: The aim of this study was to establish the carriage rate among students of the second, third and fourth year of study at the School of Medicine in Belgrade and to analyze their genotypic and phenotypic characteristics. METHODS: In total 533 nasal samples were taken. The samples were incubated inTrypcase-soy broth supplemented with 6.5% NaCl, and thereafter the swabs were inoculated on mannitol salt agar supplemented with 2 microg/mL of oxacillin. The presence of nuc, mecA and Panton-Valentine leukocidin genes was examined by PCR.The characteristics of the MRSA strains were determined using: antibiotic susceptibility testing by Vitek2 System, SCCmec, agr typing and MLST. RESULTS: MRSA was isolated from two of 533 investigated samples (0.37%). MRSA were isolated from the students of the second and third year of study. Profiles of strains were: ST80 (SCCmec type IV, agr type 3) and ST152 (SCCmec type V, agr type 1). MRSA strains were multiresistant. CONCLUSION: The nasal carriage rate of MRSA in population of medical students of the first year of study in Belgrade is low. Genotypic and phenotypic characteristics of MRSA strains indicate their community origin. MLST typing revealed that isolates belong to ST80 and ST152.

[The diagnosis of Chlamydia trachomatis cervical infection among students by using classical and molecular methods].

INTRODUCTION: Chlamydia trachomatis is the most common cause of sexually transmitted disease. The possibility of serious complications may be prevented by early detection of the bacteria on the uterine cervix by the application of sensitive and reliable tests such as up-to-date molecular tests. OBJECTIVE: The aim of the study was the comparison of sensitivity and specificity of three different methods in the diagnosis of Chlamydia trachomatis infection. METHODS: The study included 69 female students referred to the gynecological outpatient unit at the Students' Polyclinic for colposcopic examination of the uterine cervix. Cervical Chlamydia trachomatis was diagnosed by using three different methods: direct immunofluorescence (DIF), nucleic acid hybridization assay (hc2), and polymerase chain reaction (PCR). RESULTS: By using DIF Chlamydia trachomatis was identified in four students (5.80%), by using hc2 also in four (5.80%), while by using PCR test in six students (8.70%). Comparative analysis of the obtained results evidenced sensitivity and specificity rates of DIF in comparison to PCR method of 46% and 95%, respectively. Sensitivity and specificity of DIF method in comparison to hc2 was 62% and 97%. Sensitivity and specificity of hc2 method in comparison to PCR was 76% and 100%. CONCLUSION: Contemporary molecular methods, such as PCR, are methods of choice for the identification of endocervical Chlamydia trachomatis in the population of university students without symptoms of the disease.

Association between pet-keeping and asthma in school children.

BACKGROUND: The role of pet exposure in childhood asthma and allergy is still controversial. The aim of this study was to investigate the association between pet-keeping during different periods of childhood and asthma and sensitization in school children. METHODS: One hundred and forty-nine children aged between 7 and 14 years were enrolled in this study. Seventy-four children had current physician-diagnosed asthma, while 75 children did not have asthma. Pet-keeping was investigated by questionnaire. Allergic sensitization to pet allergen was assessed on skin prick tests and specific serum IgE concentration. Logistic regression analysis was performed, taking into account potential confounders. RESULTS: Early, past and current pet-keeping was not significantly associated with asthma. Neither owning a cat nor dog during childhood was associated with asthma. Early pet-keeping, however, was significantly associated with sensitization to pet allergens (adjusted odds ratio [aOR], 24.11; 95% confidence interval [CI]: 3.28-177.27). Further analysis showed that only early cat-keeping was significantly associated with sensitization to cat allergen (aOR, 51.59; 95%CI: 2.28-1167.07). Keeping a cat or a dog after the first year of life was not associated with sensitization to those allergens. CONCLUSIONS: Keeping a cat or a dog does not increase risk for asthma. Keeping a cat in the first year of life, however, increases risk of sensitization to cat allergen. Considering that this is a relatively small study, larger, prospective, birth cohort studies are required in Serbia to accurately assess the relationship between pet-keeping, asthma and sensitization.

Inhaled nitric oxide therapy for acute respiratory distress syndrome in children.

The aim of this study was to evaluate the effects of inhaled nitric oxide (iNO) therapy on oxygenation and mortality in children with acute respiratory distress syndrome (ARDS). Thirty-three children with ARDS and an arterial SatO2 <88% despite mechanical ventilation were analyzed. Patients in the iNO group were prospectively enrolled and treated with conventional therapy plus iNO. The control group consisted of retrospectively analyzed patients treated only with conventional therapy. A significant increase in PaO2/FiO2 ratio (25.6%) and decrease in oxygenation index (19.5%) was observed after 4 h of iNO treatment, when compared to baseline values. A positive response to iNO was detected in 69% of patients, and there was no difference between pulmonary and extrapulmonary ARDS. There was no difference in mortality and duration of mechanical ventilation between iNO and control group.

[Current knowledge of bacterial vaginosis].

Bacterial vaginosis, earlier termed nonspecific vaginitis (anaerobic vaginosis) because of the absence of recognized pathogens, is most common vaginal syndrome of women of childbearing age affecting 15-30%. This syndrome, whose aetiology and pathogenesis remains unknown, is characterized by significant changes in the vaginal ecosystem. These changes consist of a decrease in the number of lactobacilli and a large increase in the number of anaerobic organisms. The bacteria adhere to desquamated epithelial cells with a distinctive appearance of clue cells The main complaints of women with symptomatic bacterial vaginosis include vaginal discharge and odour. However, a significant number of all women who have bacterial vaginosis deny symptoms. Bacterial vaginosis is associated with a number of gynaecologic and obstetric complications including cervicitis, cervical neoplasia, pelvic inflammatory disease, postoperative infections, and preterm labour.The diagnosis is most frequently made based on vaginal smear stained according to Gram (Nugent scoring method). Metronidazole and clindamycin are the drugs of choice for treatment of women with bacterial vaginosis. Which women should undergo treatment? According to the prevailing attitude, it should include women with symptoms. Symptomatic women with frequent relapses of bacterial vaginosisas, as a rule, have poor response to the applied therapy. To achieve better efficiency in the treatment of such women, it is necessary to have more extensive understanding of all factors in the pathogenesis of the syndrome.

Long-term analysis of Listeria monocytogenes vaginal carriage frequency in Belgrade, Serbia (short communication).

In order to gain insight into the frequency of L. monocytogenes vaginal carriage among women of reproductive age in Belgrade, Serbia, we conducted the long-term investigation (January 1992 through August 2006) described herein. The study population of 958 women included 799 patients with spontaneous abortion and 159 patients with infertility. A low rate of L. monocytogenes vaginal carriage of 0.1% was established, since only one strain was recovered from vaginal swab of a woman with spontaneous abortion.

Quantification of biofilm in microtiter plates: overview of testing conditions and practical recommendations for assessment of biofilm production by staphylococci.

The details of all steps involved in the quantification of biofilm formation in microtiter plates are described. The presented protocol incorporates information on assessment of biofilm production by staphylococci, gained both by direct experience as well as by analysis of methods for assaying biofilm production. The obtained results should simplify quantification of biofilm formation in microtiter plates, and make it more reliable and comparable among different laboratories.

Aminoglycoside resistance in members of the Staphylococcus sciuri group.

This study investigated the prevalence of aminoglycoside resistance and genes encoding aminoglycoside-modifying enzymes in members of the Staphylococcus sciuri group. A total of 304 S. sciuri group member isolates (284 S. sciuri, 12 S. lentus, and 8 S. vitulinus) from humans (n = 34), animals (n = 133), and environmental sources (n = 137; out-hospital and hospital environment, food) were examined for their susceptibility to amikacin, gentamicin, isepamicin, kanamycin, neomycin, netilmicin, sisomicin, streptomycin, and tobramycin. The overall prevalence of resistance to aminoglycosides was low at 12.1%. Resistance to single aminoglycosides ranged from 0% to 7.2%. The aac(6')-Ie/aph(2"), ant(4')-Ia, and aph(3')-IIIa genes, either alone or in combination, were found in 16 out of 19 isolates showing resistance to nonstreptomycin aminoglycosides. Among the 22 isolates that showed resistance to streptomycin, the genes str and ant(6)-Ia were identified in 18 and 4 isolates, respectively.