Comparison of steam technology and a two-step cleaning (water/detergent) and disinfecting (1,000 resp. 5,000 ppm hypochlorite) method using microfiber cloth for environmental control of multidrug-resistant organisms in an intensive care unit.

Aim: The aim of this prospective observational study was to evaluate the impact of two cleaning and disinfecting methods and the use of steam against methicillin-resistant Staphyl ococcus aureus, vancomycin-resistant Enterococcus faecalis, carbapenem-resistant Pseudomonas aeruginosa and multidrug-resistant (MDR) Acinetobacter baumannii in a tertiary referral hospital. Methods: McFarland 0.5 suspensions (content 1.5 x 108 cfu/ml) of four challenge bacterial species were prepared and used to inoculate different sites in three ICU rooms. One of the following methods was used in each room: steam technology (Tecnovap Evo 304) resp. cleaning with microfiber cloths, soaked with detergent and water, thereafter disinfection with 1,000 ppm hypochlorite or the same procedure with 5,000 ppm hypochlorite. Qualitative microbiology and ATP bioluminescence were performed before and after cleaning with each method. The Wilcoxon test was used for paired samples to check for ordinal variables. The cost of each cleaning method was analyzed. Results: Environmental cleaning with steam technology was found to be as effective against MDR microorganisms as a two-step cleaning process (water/detergent and disinfecting with 1,000 resp. 5,000 ppm hypochlorite) in ICUs. No bacterial growth was detected after any of the three cleaning methods. Steam technology was 76% and 91% cheaper than using 5,000 ppm and 1,000 ppm hypochlorite, respectively. Conclusions: When compared to, steam technology was found to have an advantage over the 2-step procedure with cleaning and disinfection, because it avoids the use of chemicals, reduces water consumption, labor time and costs for cleaning.

Erratum to: Effect of resin infiltration on enamel surface properties and Streptococcus mutans adhesion to artificial enamel lesions.

Authors would like to add ACKNOWLEGMENT in this article, page 30, between CONCLUSION and REFERENCES as below. ACKNOWLEGMENT: This research was supported by Erciyes University Scientific Research Project Department.

Is it worth screening for vancomycin-resistant Enterococcus faecium colonization?: Financial burden of screening in a developing country.

BACKGROUND: The screening of critically ill patients at high risk of vancomycin resistant enterococci (VRE) colonization, to detect and isolate colonized patients, is recommended to prevent and control the transmission of VRE. Screening asymptomatic carriers brings financial burden for institutions. In this study, we performed risk analysis for VRE colonization and determined the financial burden of screening in a middle-income country, Turkey. METHODS: We retrospectively analyzed the VRE surveillance data from a pediatric hospital between 2010 and 2014. A case-control study was conducted to identify the risk factors of colonization. Total cost of VRE screening and additional costs for a VRE colonized patient (including active surveillance cultures and contact isolation) were calculated. RESULTS: During the 4-year period, 6,372 patients were screened for perirectal VRE colonization. The rate of culture-positive specimens among all patients screened was 239 (3.75%). The rate of VRE infection was 0.04% (n = 3) among all patients screened. Length of hospital stay, malignancy, and being transferred from another institution were independently associated risk factors for colonization. Annual estimated costs for the laboratory were projected as $19,074 (76,295/4) for all patients screened. Cost of contact isolation for each patient colonized in a ward and an intensive care unit was $270 and $718, respectively. CONCLUSIONS: In developing countries, institutions should identify their own high-risk patients; screening priorities should be based on prevalence of infection and hospital financial resources.

Serotype distribution of Streptococcus pneumoniae in children with invasive diseases in Turkey: 2008-2014.

Successful vaccination policies for protection from invasive pneumococcal diseases (IPD) dependent on determination of the exact serotype distribution in each country. We aimed to identify serotypes of pneumococcal strains causing IPD in children in Turkey and emphasize the change in the serotypes before and after vaccination with 7-valent pneumococcal conjugate vaccine (PCV-7) was included and PCV-13 was newly changed in Turkish National Immunization Program. Streptococcus pneumoniae strains were isolated at 22 different hospitals of Turkey, which provide healthcare services to approximately 65% of the Turkish population. Of the 335 diagnosed cases with S. pneumoniae over the whole period of 2008-2014, the most common vaccine serotypes were 19F (15.8%), 6B (5.9%), 14 (5.9%), and 3 (5.9%). During the first 5 y of age, which is the target population for vaccination, the potential serotype coverage ranged from 57.5 % to 36.8%, from 65.0% to 44.7%, and from 77.4% to 60.5% for PCV-7, PCV-10, and PCV-13 in 2008-2014, respectively. The ratio of non-vaccine serotypes was 27.2% in 2008-2010 whereas was 37.6% in 2011-2014 (p=0.045). S. penumoniae serotypes was less non-susceptible to penicillin as compared to our previous results (33.7 vs 16.5 %, p=0.001). The reduction of those serotype coverage in years may be attributed to increasing vaccinated children in Turkey and the increasing non-vaccine serotype may be explained by serotype replacement. Our ongoing IPD surveillance is a significant source of information for the decision-making processes on pneumococcal vaccination.

Molecular epidemiology of quinolon resistant strains of extended spectrum beta-lactamase producing Escherichia coli.

OBJECTIVE: To determine the clonal relationship of ESBL-producing and quinolone resistant E.coli strains and to investigate the risk factors for infections with these microorganisms. METHODS: A total of 95 ESBL-producing and quinolone resistant E.coli strains isolated from various clinical specimens of inpatients and outpatients in our hospital were included in the study. Risk factors for infections with ESBL-producing E.coli and demographic data of the patients were obtained from hospital records. The rep-PCR method was used for the determination of the genetic relationship of the strains. RESULTS: Of the strains included in the study, 33(34.7%) were isolated from inpatients and 62(65.3%) from outpatients. At least one risk factor has been identified in all patients for infection with ESBL producing E.coli and the mean of the risk factors of patients was 4.2. The most common risk factor was urinary catheter insertion (57.9%). The distribution of the strains in each clone was as fallows: clone A: 9(9.5%), clone B: 10(10.5%), clone C: 38(40%), clone D: 12(12.5%), clone E: 6(6.3%), clone F: 7(7.3%) and clone G 5(5.3%). The clones A, D and C (dominant clone) were isolated from hospital and community acquired infections. Clones E, F and G were identified as nosocomial clones. CONCLUSION: Infections with multidrug resistant bacteria may be related to the hospital although they were isolated from outpatients. Developing a medical record system is vitally important to prevent the occurence and spread of resistant bacterial infections in the community.

The relationship between holding time and the bacterial load on surgical instruments.

The aim of this investigation was to determine the bacterial load on used instruments and to evaluate the relationship between the bacterial load and the holding time prior to cleaning. Thirty six sets were evaluated to establish the average number of bacteria per square centimeter. For the experimental study, three different bacteria were prepared in sheep blood and used to contaminate sterile stainless steel pieces with the surface of 10 cm(2). After incubation at room temperature for 2, 4, 6, 8, 12, 24, 36, and 48 h, colonies were counted and compared to time zero. Bacterial counts were between 10 and 250 CFU/cm(2), depending on the operation site. Bacterial load was found to have increased after 6 h. An increase of 3log10 CFU/cm(2) was measured after 12 h. It is imperative to clean surgical instruments in the first 6 h to ensure effective disinfection and sterility.

Effect of resin infiltration on enamel surface properties and Streptococcus mutans adhesion to artificial enamel lesions.

The aim of this study was to evaluate and compare the effects of resin infiltration and sealant type on enamel surface properties and Streptococcus mutans adhesion to artificial enamel lesions. Artificial enamel lesions were produced on the surfaces of 120 enamel specimens, which were divided into two groups: Group A and Group B (n=60 per group). Each group was further divided into four subgroups (n=15 per subgroup) according to sealant type: Group I-Demineralized enamel (control); Group II-Enamel Pro Varnish; Group III-ExciTE F; and Group IV-Icon. In Group A, hardness and surface roughness were evaluated; in Group B, bacterial adhesion was evaluated. Icon application resulted in significantly lower surface roughness and higher hardness than the other subgroups in Group A. In Group B, Enamel Pro Varnish resulted in lowest bacterial adhesion, followed by Icon. This study showed that resin infiltration of enamel lesions could arrest lesion progress.

In vitro synergism of combinations of colistin with selected antibiotics against colistin-resistant Acinetobacter baumannii.

AIM: The in vitro activity of colistin in combination with sulbactam, netilmicin, and vancomycin against colistin-resistant A. baumannii strains was investigated. Furthermore, the clonal relationship of the strains was analyzed. METHODS: Clonal relationship was investigated using rep-PCR. To screen for synergysm, the fractional inhibitory concentration index (FICI) was calculated using checkerboard assay. The killing kinetics of the combination of colistin with vancomycin was assessed using time-kill assay. RESULTS: Three different clones were found among 10 clinical isolates of colistin-resistant A. baumannii strains. Thereof, 8 strains were susceptible to netilmicin. Synergistic interaction was detected in 1 strain with the combination of colistin-netilmicin, in 5 strains with colistin-sulbactam, and in 9 strains with colistin-vancomycin. None of combinations had antagonistic activity. Colistin-vancomycin combination resulted in rapid bactericidal activity. CONCLUSION: These results show a distinct in vitro synergism between colistin and vancomycin, which might be useful to treat infection with multiple-resistant strains, prevent emergence of resistant strains, and to lower doses for both antibiotics to be used.

An unpredicted side effect of prophylactic antibiotic use.

INTRODUCTION AND OBJECTIVE: We investigated the effects of cefazolin sodium (CS), on wound healing in rats. MATERIAL AND METHOD: Forty rats in which an incisional wound model was created by removing two skin strips (4×1 cm), and suturing the wound edges, were included. Four groups were formed in a randomized way with each having 10 rats. The Control group (Group 1) received 1 cc 0·9% NaCl twice daily, whereas Group 2 received single-dose preoperative 30 mg/kg CS, Group 3 received single-dose preoperative 30 mg/kg CS followed by the same dose for three postoperative days, and Group 4 received single-dose preoperative 30 mg/kg CS followed by the same dose for seven postoperative days (via i.p. route). On the first day of the study, as the wound was created, a skin strip of 1×1 cm area was collected for bacteriologic examination. On the third day, specimens were acquired from the incision for histopathologic examination. The rats were sacrificed on the seventh day and more specimens were gained for histopathologic, tensiometric, and bacteriologic tests. RESULT: Group 4 demonstrated disrupted normal skin flora; reduced inflammatory cell density, fibroblastic activity, and collagen density; and decreased wound tensile strength. The histopathologic findings with Groups 2 and 3 were as same as with Group 4 and wound tensile strength showed no significant difference compared with the Control group. Group 2 revealed no significant difference compared with the Control group with regard to all parameters. DISCUSSION: Seven-day CS therapy had a negative effect on wound healing and changed the normal skin flora.

[Epidemiology, clinical and microbiological characteristics of invasive streptococcal infections in Turkey, 2010-2011]. / Türkiye'de invazif streptokok enfeksiyonlarinin epidemiyolojisi, klinik ve mikrobiyolojik özellikleri, 2010-2011.

A one-year active surveillance study was conducted to investigate the epidemiological and microbiological characteristics of invasive group A streptococci (GAS) infections in Turkey and to provide data for the establishment of national preventive strategies related to invasive GAS infections. A total of 46 clinical microbiology laboratories from 12 different regions of Turkey (Istanbul; Eastern and Western Marmara; Eastern and Western Blacksea; Aegean; Mediterranean; Western, Central, Northeastern, Middle-eastern and Southeastern Anatolia) participated in the study. Accordingly, GAS strains isolated from sterile body sites (blood, cerebrospinal, synovial, pleural, peritoneal, pericardial fluids) in the study centers between June 2010-June 2011, were sent to Maltepe University Hospital Clinical Microbiology Laboratory for microbiological confirmation and further analysis. The isolates were identified by conventional methods, and for serotyping, opacity factor (OF) and T protein types were investigated. For genotyping GAS lysate preparation, emm gene amplification and sequencing were performed by using the protocols recommended by Centers for Disease Control and Prevention. A total of 65 invasive GAS strains were isolated in 15 of the participant centers, during the study period. The rate of invasive GAS isolation exhibited regional variation, with the highest rates in the Eastern Blacksea (Trabzon, n= 19), followed by Istanbul (n= 17) and Western Anatolia (Ankara, Konya, n= 14). Of the patients with invasive GAS infection 33 were female, 32 were male, with the age range of 0-89 years. GAS strains were most commonly isolated from soft tissue specimens (n= 18), followed by abscess material (n= 10), sterile body fluids (n= 8) and blood (n= 7) samples. Serotyping revealed that 55% (36/65) of the strains were OF positive, and the majority of T protein was polygroup T (n= 20), followed by U (n= 14), B (n= 5), X (n= 3) and Y (n= 2). T protein was not detected in 22 isolates. The strains were found to have 17 different emm types;emm1 (n= 13), emm4 (n= 6), emm6 (n= 6), emm12 (n= 6), emm24 (n= 4), emm14 (n= 3) and emm28 (n= 3). Nine of the strains could not be typed by sequencing. The correlation between emm typing and serotyping was detected as 58%. It was observed that 26-valent vaccines included 70.5% of the invasive GAS strains included in this study. Our study provided initial data concerning the epidemiological properties of invasive GAS infections and characterization of GAS strains in Turkey. The incidence of invasive GAS infections is low in our country. Although immunization programme by 26-valent GAS vaccine is not currently an urgent public health issue for our country, the results of this study indicated that emm types 4 and 24 should better be included in such a vaccine to be used in Turkey. Additionally, since epidemiological features of GAS infections and the microbiological characteristics of the strains can vary by time, for the diagnosis of invasive streptococcal infections and to take the necessary preventive measures, epidemiological studies should be conducted repeatedly.

Relationship between odontogenic bacteremia and orthodontic stripping.

INTRODUCTION: The aim of this study was to evaluate the prevalence of bacteremia associated with an orthodontic stripping procedure. METHODS: The study included 29 orthodontic patients (mean age, 18.2 ± 3.4 years). We used a standardized stripping procedure: a perforated stripping disk with a contra-angle hand piece was used at a low speed (<15,000 rpm; 10 seconds) on the mandibular anterior teeth. Blood samples were collected by inserting a cannula into the left antecubital fossa. A baseline sample was taken before treatment, and a second sample was taken after the stripping procedure. These samples were inoculated into aerobic and anaerobic blood culture bottles and incubated, and the bacterial cultures were identified; the samples collected before and after the stripping procedure were statistically analyzed. RESULTS: Transient bacteremia was not detected in any pretreatment blood sample, but it was found in 1 postoperative blood sample; this sample tested positive for Streptococcussanguis. CONCLUSIONS: The bacterial species in the positive postoperative blood sample was S sanguis, which might be associated with infective endocarditis. Clinicians should explain the level of risk to the patient and consult a concerned medical specialist.

Microbiology of Brucella.

The genus Brucella is a member of family Brucellaceae and includes ten species which are small, non-motile, non-sporing, aerobic, gram-negative intracellular coccobacilli. They are catalase, oxidase and urea positive bacteria. Members of the genus can grow on enriched media like blood agar or chocolate agar. Identification in species level can be done by agglutination with monospecific serum, cultivating the strains in the presence of dyes and/or with PCR methods. Antigenic structure of the Brucella is composed of surface, intracellular, and in vivo antigens. Thanks to various virulence factors that act as metabolic regulators, Brucella strains can protect themselves from immune system of the host, adapt easily to different environmental conditions, and multiply intracellular. Classification, epidemiological features, isolation and identification, antigenic structure and virulence factors of Brucella species along with the discussion of very few patents associated with Brucellosis have been reviewed in this paper.

[Comparison of ertapenem-EMB Agar with traditional methods for screening carbapenem-resistant Klebsiella pneumoniae from rectal swabs]. / Rektal Sürüntü Örneklerinde Karbapeneme Dirençli Klebsiella pneumoniae Taranmasinda Klasik Yöntemlerle Ertapenemli EMB Besiyerinin Karsilastirilmasi

Detection of rectal colonization with carbapenem-resistant Klebsiella pneumoniae (CRKP) is the most important step in the infection control protocols in order to prevent infections caused by CRKP which has an increasing incidence all over the world. In this study, it was aimed to compare the detection rate of 2 mg/L ertapenem EMB agar medium with the other methods recommended by various international guidelines. These methods include direct plate method using ertapenem disc, enrichment method in tryptic soy broth containing 2 mg/L ertapenem and the investigation of the predominant betalactamases in the colonized patients. The lowest inoculum detected by different methods was determined by using simulative challenge test prepared for this purpose. The ability to detect CRKP from rectal swabs was evaluated by using the clinical specimens of 801 patients. For all bacteria isolated, carbapenem susceptibility was evaluated by using E-test method, the presence of beta-lactamases was determined by using modified Hodge test (MHT), and the carbapenemase genes were investigated by using multiplex polymerase chain reaction (PCR). The lowest inoculum detected by ertapenem-EMB agar was 50 CFU/mL whereas the lowest inocula were 1 x 105 and 1 x 103, respectively by tryptic soy broth with ertapenem and direct plate method. No resistance gene were identified by PCR in 13 (39.4%) of 33 isolates, whereas blaOXA-48 was detected in 19 (95%) and blaIMP in 1 (5%) of 20 positive isolates. All of the positive strains were resistant to imipenem and ertapenem, while 2 (10%) strains were found to be susceptible to doripenem and meropenem. While MHT was negative in all strains which were negative for resistance genes, all resistance gene positive strains except one blaOXA-48 strain that was also sensitive to doripenem and meropenem, were found to be positive with MHT. According to the results of PCR, the sensitivities of the three methods were found to be 80%. The specificities, positive and negative predictive values were found to be 15.4%, 59% and 33.3% for ertapenem-EMB agar, 23%, 61.5% and 42.9% for broth with ertapenem and 61.5%, 76% and 66.6% for direct plate method, respectively. Average labor time of the methods (isolation + identification + sensitivity + MHT) was determined as 48 hours for ertapenem-EMB agar, whereas it was 96 hours for the other methods. In conclusion, since ertapenem- EMB agar method is a sensitive and rapid method, it can be used safely for the preliminary detection of CRKP without increasing the workload of the laboratory.

Intravitreal tigecycline treatment in experimental Acinetobacter baumannii endophthalmitis.

PURPOSE: To investigate the clinical and microbiological effectivity of intravitreal tigecycline in an experimental rabbit endophthalmitis model caused by imipenem resistant Acinetobacter baumannii. MATERIALS AND METHODS: Forty-eight eyes of 24 New Zealand white albino rabbits were divided into six groups (n=8 in each). The right eyes were divided into three groups and defined as infected group; left eyes were divided into three groups and defined as uninfected group. Infected group received 0.1 ml intravitreal A. baumannii suspension. Twenty-four hours after bacterial inoculation, group 1 received 1 mg/0.1 ml tigecycline and group 2 received 0.5 mg/0.1 ml tigecycline. Group 3 eyes received no treatment. In group 4, 0.1 ml of saline solution was injected. Groups 5 and 6 were received intravitreal tigecycline injection of 1 mg/0.1 ml and 0.5 mg/0.1 ml respectively. The eyes were enucleated for histopathological evaluation on the sixth day. Clinical and histological scoring systems were used to evaluate clinical and histological severity of the intraocular infection. RESULTS: The mean clinical scores of the six groups at the sixth day were 11±1.92, 12.4±6.2, 8.5±2.7, 0, 3±1.3, and 3±1.4 respectively. Mean histopathological scores were 7.8±2.8, 7.0±1.5, 5.6±1.4, 0, 0, and 0 respectively. There was no significant difference in mean clinical and histopathological scores of infected group (groups 1, 2 and 3). There was significant difference in mean clinical scores of groups 5 and 6 compared with group 4. Groups 4, 5 and 6 showed normal histological structure in histopathological evaluation and showed no significant difference. Microbiological cure was achieved in all infected eyes. CONCLUSIONS: Experimental rabbit endophthalmitis model caused by imipenem resistant A. baumannii was microbiologically cured by intravitreal tigecycline injection. However, a hypersensitivity-like reaction due to intravitreal application of tigecycline limits the use of this antimicrobial agent in A. baumannii endophthalmitis.

Antimicrobial susceptibility and molecular subtyping of 55 Turkish Bacillus anthracis strains using 25-loci multiple-locus VNTR analysis.

Anthrax, which is caused by the bacterium Bacillus anthracis, is one of the oldest documented infectious diseases in both livestock and humans. The differentiation of B. anthracis strains is difficult because of their highly homogeneous genomes. We used multiple-locus variable-number tandem repeat analysis (MLVA) with 25 markers to genotype 55 B. anthracis isolates from 16 distinct regions of Turkey. The antimicrobial susceptibility of the isolates was investigated using the agar dilution method. An eight-loci MLVA assay revealed six unique genotypes (G(K)13, G(K)27, G(K)35, G(K)43, G(K)44, and G(K)61). However, the 25-loci MLVA was more discriminatory, revealing the presence of ten genotypes instead of six. The additional genotypes resulted from the split of four subtypes: G(K)35 (b and c), G(K)43 (a and f), G(K)44 (d and e), and G(K)61 (i and j). All of the Turkish B. anthracis isolates were susceptible to ciprofloxacin, levofloxacin, tigecycline, linezolid, and vancomycin. One isolate was resistant to penicillin and to doxycycline. A total of 34 isolates were susceptible, 20 isolates were partially susceptible, and one isolate was resistant to erythromycin. None of the isolates exhibited susceptibility to cefotaxime. A total of 53 isolates were susceptible to gentamicin, and two were resistant. The genotypes G(K)35 (n=24), G(K)44 (n=13), and G(K)43 (n=10) were the most prevalent in 10, 6, and 5 regions, respectively, of the total 16 provinces. The B. anthracis isolates collected from these regions implied that the movement of B. anthracis is a result of the increased transportation of livestock and the resultant cross contamination.

Locking tunneled hemodialysis catheters with hypertonic saline (26% NaCl) and heparin to prevent catheter-related bloodstream infections and thrombosis: a randomized, prospective trial.

OBJECTIVE: Tunneled cuffed dual-lumen catheters (TCCs) are commonly used for vascular access in hemodialysis (HD) patients. Catheter-related bloodstream infection (CRBSI) is the major problem leading to morbidity and mortality. We investigated whether 26% NaCl solution has any favorable effect on the infections and thrombosis caused by HD catheters. METHODS: TCCs were locked with either 26% NaCl and heparin or standard heparin. The primer end point of the study was the CRBSI or thrombosis of the TCC. We compared the antimicrobial activity of the NaCl solutions (6.5%, 13%, 26%) with 0.9% NaCl solution by time-kill kinetic assay. All tests were performed in triplicate by incubation of test fluids with Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis. RESULTS: The mean catheter survival was significantly higher in the 26% NaCl and heparin group (129.5 ± 50.1 catheter days to 103.3 ± 59.8, p = 0.008). CRBSI rates (10-15.4%) did not differ significantly between the two groups (p = 0.54). The hypertonic 13% NaCl solution had bactericidal effects on E. coli and P. aeruginosa, but had bacteriostatic effect on S. aureus and S. epidermidis. CONCLUSION: In this study we demonstrated that the 13% NaCl solution and more hypertonic NaCl solutions revealed potent in vitro antimicrobial properties against all checked Gram-negative microorganisms.

[Genotyping of nosocomial methicillin-resistant Staphylococcus aureus strains isolated from clinical specimens by rep-PCR]. / Klinik Örneklerden Izole Edilen Hastane Kaynakli Metisiline Dirençli Staphylococcus aureus Suslarinin rep-PCR ile Genotiplendirilmesi.

Methicillin-resistant Staphylococcus aureus (MRSA) infections are associated with increased cost, mortality and length of hospital stay compared with the other infections. Therefore, controlling the spread of this pathogen by screening patients, personnel and the environment remains as a high priority in infection control programs. The aim of this study was to detect the clonal relationship between nosocomial MRSA strains by using repetitive-sequence-based polymerase chain reaction (rep-PCR) method which has several advantages owing to its speed and ease of use. A total of 100 MRSA stock strains that had been isolated from various clinical samples of hospitalized patients in Erciyes University Medical Faculty Hospitals between September 2008-October 2009, were included in the study. Methicillin resistance of the strains were determined by cefoxitin disc diffusion test according to CLSI guidelines. Rep-PCR (Diversilab, bioMerieux, France) method was performed in the following four steps in order to determine genetic proximity of MRSA strains: (1) Manual DNA extraction (UltraClean Microbial DNA Isolation Kit; MoBio Laboratories, USA), (2) Rep-PCR by using fingerprinting kits in the thermocycler (Diversilab DNA Fingerprinting Kit), (3) Automated microfluidic electrophoresis by bioanalyzer (Diversilab DNA LabChip kit), (4) Analysis and rapid evaluation with the use of web-based DiversiLab software (version 2.1.66). Rep-PCR analysis have shown the presence of a total 11 clones, including 3 major clones [A (4 subtypes), B (2 subtypes) and C (2 subtypes)] and 8 unique clones (DK). Clone A was found to be the dominant type. Seventy-eight percent of the 100 MRSA isolates belonged to clone A (63 were A1; 9 were A2; 4 were A3, 2 were A4), 11% belonged to clone B (10 were B1, 1 was B2), 3% belonged to clone C (2 were C1, 1 was C2), and one of each belonged to the other clones (D, E, F, G, H, I, J, K). Clone A was isolated from 93.3% (14/15) of the samples sent from internal diseases intensive care unit (ICU), from 66.6% (10/15) of the samples sent from infectious diseases ward and 91% (10/11) of hematology-oncology ward samples. All MRSA strains isolated from anesthesiology and newborn ICU were of clone A. The isolation dates of these strains were in proximity. In conclusion, MRSA strains showed clonal dissemination in our hospital, clone A being the predominant one during the study period. Rep-PCR which is a rapid and reliable method, can easily be applied for molecular epidemiological purposes and aid to infection control measures.

[Comparative evaluation of e-test and disk diffusion methods for susceptibility testing of Nocardia species]. / Nocardia Klinik Izolatlarinin Antibiyotik Duyarliliklarinin Belirlenmesinde E-Test ve Disk Difüzyon Yöntemlerinin Karsilastirilmasi

Variations in antimicrobial susceptibility among different Nocardia species limit the options for therapy. It is very difficult to perform antimicrobial susceptibility testing of these bacteria due to their slow growth rate and problems in inoculum preparation. The aim of this study was to compare E-test and disk diffusion methods for the determination of antimicrobial susceptibilities of Nocardia isolates. Since E-test is considered as 90% consistent with the gold standard microdilution method recommended by Clinical and Laboratory Standards Institute (CLSI), it was chosen for comparison with disk diffusion and in order to determine the use of disk diffusion in routine practice. A total of 21 Nocardia strains isolated from clinical specimens (12 lung, 7 brain and 2 skin/soft tissue samples) were included in the study. Six of the isolates were identified as N.asteroides, six were N.farcinica, five were N.cyriacigeorgica and four were Nocardia spp. By conventional methods. Susceptibilities of strains to ampicillin, ampicillin-sulbactam, amoxicillin-clavulanic acid, ceftazidime, sefepime, imipenem, gentamicin, erythromycin, levofloxacin, moxifloxacin, trimethoprim- sulfamethoxazole, piperacillin-tazobactam, tigecycline, and linezolid were investigated by using E-test and/or disk diffusion methods. The results were interpreted according to the CLSI breakpoints for Staphylococcus spp. All of the strains were found to be resistant to ceftazidime, piperacillin-tazobactam and ampicillin, however susceptible to levofloxacin, moxifloxacin, trimethoprim-sulfamethoxazole tigecycline, and linezolid. The concordance between the methods in terms of susceptibility testing were 100% for ampicillin, ceftazidime, imipenem, gentamicin and linezolid; 85.7% for erythromycin, 76.2% for sefepime, 73.7% for moxifloxacin, 71.4% for piperacillin-tazobactam, 70% for ampicillin-sulbactam and 46.2% for amoxicillin- clavulanic acid. In conclusion, the therapy must be planned according to the results of antimicrobial susceptibility testing. Disk diffusion is not a reliable method due to the high rates of very major errors. E-test would be an alternative method being practical and easily evaluated, especially in routine laboratories in which the reference method could not be performed.

Changing pattern of antibiotic susceptibility in intensive care units: ten years experience of a university hospital.

The study was performed to assess microorganisms and antibiotic susceptibility patterns during ten years in intensive care units of a University Hospital. Infection Control Committee has active, prospective surveillance in ICUs for thirteen years. Ten years data of ICUs was evaluated retrospectively from surveillance forms. Microorganisms and their antibiotic resistance were recorded according to the years. During ten years, gram negative microorganisms were the most frequent isolated microorganisms from clinical specimens. Acinetobacter baumannii (21.8%), Pseudomonas aerigunosa (16%), Escherichia coli (10.4%) and Klebsiella pneumoniae (8%) were the most common gram negative microorganisms. However, Staphylococcus aureus was the most prevalent gram positive microorganism, the incidence decreased from 18.6% to 4.8% during ten years. Also antibiotic susceptibility of microorganisms changed during ten years. Carbapenem resistance increased from 44% to 92% in A. baumannii and ciprofloxacin resistance increased in E. coli from 28% to 60% and in K. pneumoniae from 21% to 55% during ten years. However, methicilin resistance decreased in S. aureus from 96% to 54%. In conclusion, antibiotic resistance is growing problem in ICUs. Rationale antibiotic policies and infection control measures will prevent the development of resistance.