Canan Külah

Characterisation of carbapenem-resistant Acinetobacter baumannii outbreak strains producing OXA-58 in Turkey

The aim of this study was to characterise the molecular epidemiology and mechanisms of carbapenem resistance of nosocomial Acinetobacter baumannii isolates in a new university hospital in Turkey. A total of 145 carbapenem-resistant A. baumannii (CRAB) isolates were collected during the period 2003-2006. All isolates were typed by amplified fragment length polymorphism (AFLP) analysis. AFLP analysis showed three predominant clusters consisting of 72, 20 and 12 clinical strains as well as some smaller clusters and 23 unique strains. The three main clonal AFLP types corresponded to three major antibiotic susceptibility patterns. One environmental isolate was found related to the major outbreak clone. The reference type strains of European clones I, II and III were also typed by AFLP and analysed for clonal similarity. Polymerase chain reaction (PCR) analysis of different carbapenem resistance genes showed that strains from each of the three main clusters as well as 79% of the remaining strains harboured the bla(OXA-58) gene. No genes encoding the metallo-beta-lactamases GIM-1, SIM-1, SPM-1, IMP-like and VIM-like or the oxacillinases OXA-24-like and OXA-23-like were detected. In conclusion, multiple clones of CRAB strains producing OXA-58-type oxacillinase were responsible for a sustained CRAB outbreak occurring in a hospital in Turkey. These isolates were not associated with A. baumannii strains of the major European clones I, II or III.

Detecting imipenem resistance in Acinetobacter baumannii by automated systems (BD Phoenix, Microscan WalkAway, Vitek 2); high error rates with Microscan WalkAway

BackgroundIncreasing reports of carbapenem resistant Acinetobacter baumannii infections are of serious concern. Reliable susceptibility testing results remains a critical issue for the clinical outcome. Automated systems are increasingly used for species identification and susceptibility testing. This study was organized to evaluate the accuracies of three widely used automated susceptibility testing methods for testing the imipenem susceptibilities of A. baumannii isolates, by comparing to the validated test methods.MethodsSelected 112 clinical isolates of A. baumanii collected between January 2003 and May 2006 were tested to confirm imipenem susceptibility results. Strains were tested against imipenem by the reference broth microdilution (BMD), disk diffusion (DD), Etest, BD Phoenix, MicroScan WalkAway and Vitek 2 automated systems. Data were analysed by comparing the results from each test method to those produced by the reference BMD test.ResultsMicroScan performed true identification of all A. baumannii strains while Vitek 2 unidentified one strain, Phoenix unidentified two strains and misidentified two strains. Eighty seven of the strains (78%) were resistant to imipenem by BMD. Etest, Vitek 2 and BD Phoenix produced acceptable error rates when tested against imipenem. Etest showed the best performance with only two minor errors (1.8%). Vitek 2 produced eight minor errors(7.2%). BD Phoenix produced three major errors (2.8%). DD produced two very major errors (1.8%) (slightly higher (0.3%) than the acceptable limit) and three major errors (2.7%). MicroScan showed the worst performance in susceptibility testing with unacceptable error rates; 28 very major (25%) and 50 minor errors (44.6%).ConclusionReporting errors for A. baumannii against imipenem do exist in susceptibility testing systems. We suggest clinical laboratories using MicroScan system for routine use should consider using a second, independent antimicrobial susceptibility testing method to validate imipenem susceptibility. Etest, whereever available, may be used as an easy method to confirm imipenem susceptibility.

Identification of Candida species isolated from patients in intensive care unit and in vitro susceptibility to fluconazole for a 3‐year period

Species level identification of Candida and antifungal susceptibility testing is not generally performed in routine laboratory practice. There is limited information about the distribution of Candida species and antifungal susceptibility in Turkey. In this study, we aimed at identifying Candida isolates to species level from various samples obtained from patients treated in an intensive care unit between 2002 and 2005 and to evaluate fluconazole susceptibilities of the isolates. A total of 320 Candida isolates obtained from 270 patients were identified by conventional methods and using API (Candida and/or 20C AUX) system. Antifungal susceptibility testing was performed by broth microdilution method. Candida albicans was isolated with the highest frequency (65.6%) followed by C. parapsilosis (11.3%), C. glabrata (8.8%) and C. tropicalis (7.8%). Of all the isolates, 92.9% revealed susceptibility to fluconazole. Susceptibility to fluconazole was highest for C. albicans followed by C. parapsilosis and C. glabrata. The MIC90 values for C. albicans, C. parapsilosis, C. glabrata and C. tropicalis were 1, 2, 8 and 4 μg ml−1 respectively. Fluconazole remains effective against both C. albicans and the majority of non‐albicans Candida species. In this study, we determine the distribution of Candida species and evaluate the susceptibilities of the isolates, particularly for the azoles.

Asymptomatic Brucella bacteraemia and isolation of Brucella melitensis biovar 3 from human breast milk

Brucellosis is a zoonotic disease and virtually all infections derived from exposure to animals or ingestion of unpasteurized dairy products. Brucellosis among family members has been reported. However, screening household members of an index case of acute brucellosis is not a routine procedure. A 10-y-old boy was diagnosed with acute brucellosis. Unpasteurized goat cheese commonly consumed within the family was thought to be the possible source of the bacteria. The family (parents, sister and brother) was screened with physical examination, serum tube agglutination test, blood cultures and routine laboratory tests. Three additional cases (parents and sister) of serological and culture proven brucellosis were detected. Two of them (mother and sister) were asymptomatic and had no clinical findings. Brucella melitensis biovar 3 was isolated from breast milk culture and from all blood cultures of 4 brucellosis cases. In conclusion, brucellosis, even with bacteraemia, can be completely asymptomatic. Consumption of raw milk products by household members is a common risk factor for brucellosis outbreak among family members. Thus, screening household members of an index case of brucellosis can expose new brucellosis cases.

First isolation of vancomycin-resistant enteroccoci and spread of a single clone in a university hospital in northwestern Turkey

Reported here is the first isolation of vancomycin-resistant Enterococcus (VRE) at a hospital in northwestern Turkey and a description of the ensuing outbreak investigation. The first isolate was obtained from a wound culture of a patient in an intensive care unit. Thereafter, a total of 205 rectal swabs, 67 skin swabs and 123 environmental samples were screened, revealing five more VRE isolates. All isolates showed similar antibiotic resistance patterns, except for two that differed regarding gentamicin resistance. The vanA gene was present in all isolates. Pulsed-field gel electrophoresis demonstrated that all isolates belonged to a single clone, with the gentamicin-resistant isolates demonstrating two-band differences. This is the first outbreak to be caused by spread of a single VRE clone in Turkey; it was successfully controlled by strict adherence to appropriate infection control practices.

Activity of a dry mist-generated hydrogen peroxide disinfection system against methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii

BACKGROUND The aim of this study was to evaluate the activity of a dry mist-generated hydrogen peroxide (DMHP) system (Sterinis; Gloster Sante Europe, Labege cedex, France) against methicillin-resistant Staphylococcus aureus (MRSA) and Acinetobacter baumannii. METHODS McFarland 0.5 suspensions of 2 test bacteria, either pure or containing 5% sterile serum, were prepared and inoculated onto sterile stainless steel disks. Each disk in a Petri dish-with the Petri dish cover either closed or open-was placed in different locations in an intensive care unit room. Quantitative cultures were performed after the cycle. RESULTS No growth occurred on the disks in the absence of a barrier, except 1 disk containing serum. Existence of a barrier, as a drawer or a covered Petri dish, caused failure in the disinfection activity. The mean reduction in initial log(10) bacterial count was lower for both of the test bacteria in presence of a barrier: 4.44- to 4.70-log(10) colony-forming units (cfu) decrease was observed in absence of a barrier, whereas 1.49- to 3.79-log(10) cfu decrease was observed in presence of a barrier. When the culture results were compared according to organic load content, the mean (±standard deviation) reduction of initial contamination in pure and in serum containing MRSA suspensions was 4.25 ± 1.20- and 3.34 ± 1.89-log(10) cfu, respectively. The mean (±standard deviation) reduction in pure and in serum containing A baumannii suspensions was 4.34 ± 0.89- and 3.87 ± 1.26-log(10) cfu, respectively. The differences were statistically significant (P < .001). CONCLUSION Sterinis was capable of killing MRSA and A baumannii on open surfaces; however, it was not effective in closed or semiclosed areas. Presence of serum also caused failure in the disinfection activity of the system.

Evaluation of the prevalence of enterotoxigenic Bacteroides fragilis and the distribution bft gene subtypes in patients with diarrhea.

The aim of this study was to determine the prevalence of enterotoxigenic Bacteroides fragilis (ETBF) in the patients with diarrhea in our region and to assess the association between diarrhea and bft gene subtypes. The presence of ETBF and bft gene subtypes were investigated in 200 stool samples from patients with diarrhea, diagnosed as gastroenteritis, which were sent to Clinical Microbiology Laboratory at Zonguldak Karaelmas University, Training and Research Hospital and in 200 stool samples from age-matched healthy subjects between April 14, 2009 and October 28, 2009. Nested - polymerase chain reaction was used to detect the presence of bft gene directly from stool samples. The bft gene subtypes were determined by PCR in case of ETBF detection. The presence of bft gene was detected in 29 (15%) of patients and 27 (14%) of control group. bft-1 and bft-2 were found in 24 and five stool samples from 29 diarrheic patients with ETBF, respectively. Among 27 control patients with ETBF, bft-1 and bft-2 were found in 24 and three samples, respectively. No bft-3 subtypes were identified in our study. ETBF was found as a single pathogen in 9% of the patients with diarrhea, while there was an accompanying pathogen in 6% of the patients. The proportion of coinfection with another pathogen among ETBF positive patients was 38%. Cooccurance with ETBF was present in nine of 18 patients with Rotavirus and two of five patients with Entamoeba histolytica. In conclusion; there was no statistically significant difference between the prevalence of ETBF in diarrheal patients and that of the control group. When the patients and controls were compared for each age group, no statistically significant difference in ETBF rates was found. There was no significant difference between groups with respect to bft subtypes; bft-1 was identified as the most common subtype. The rate of coinfection of ETBF and Rotavirus was high.

Colonic Tuberculosis Mimicking Tumor Perforation: A Case Report and Review of the Literature

Although the exact relationship between colonic tuberculosis and carcinoma of the colon is not well known, a number of studies published in the literature have reported that these two pathologies can be found at the same patient, coincidentally. Coexistence of colonic adenocarcinoma, tuberculosis, and abscess at the same anatomic location in a patient is an extremely rare condition. We herein report the second case of colonic adenocarcinoma together with colonic tuberculosis and abscess , which was diagnosed by polymerase chain reaction (PCR) identification of Mycobacterium tuberculosis of paraffin-embedded biopsy specimens, mimicking the tumor perforation.

Extrinsic contamination of liquid soap with various gram-negative bacteria in a hospital in Turkey.

From the Division of Infectious Diseases, Department of Medicine, Eastern Virginia Medical School, Norfolk, Virginia (both authors). Address reprint requests to Tariq Iqbal, MD, Eastern Virginia Medical School, 825 Fairfax Avenue, Suite 410, Norfolk, VA 23507 (bluestarl23@ gmail.com). Infect Control Hosp Epidemiol 2010; 31(11):1198-1199

Six-year distribution pattern of hepatitis C virus in Turkey: a multicentre study

ABSTRACT Hepatitis C infection is a public health problem. The aim of this retrospective study was to determine the distribution of hepatitis C virus (HCV) genotypes in seven regions of Turkey, by evaluating 7002 patients with chronic HCV in a six-year period. During the 2009–2014 period, serum/plasma samples from 7002 new consecutive HCV RNA positive patients were collected. The female patients were 3867 (55.2%). The genotype distribution of HCV patiens was evaluated by ages and years. Statistical analysis was performed by using the Mann–Whitney test and the χ2 analysis. During the six-year period, genotype 1b was the most common genotype (67.7%) followed by untypeable genotype 1 (7.7%), genotype 4 (7.3%) and genotype 3 (6.7%). In 2014, genotype 3 was the second most common one (11.3%) and genotype 4 was the third most common one (9.8%). In the group with <25 years old patients, genotype 1b was most common (78.48%, 62/79) between the years of 2009 and 2011, whereas genotype 3 (34.8%, 86/247), between the years of 2012 and 2014. Genotype 1b was the most common in the groups between 26 and 35 years, 36 and 45 years, 46 and 55 years, 56 and 65 years. The rate of genotype 3 was increased from 4.78% to 10.06% and the rate of genotype 4 was increased from 1.3% to 3.84%, from 2009–2011 to 2012–2014. In recent years, genotypes 3 and 4 have gained importance. New therapeutic strategies and survey studies may be required for the modified HCV genotype pattern.