Antimicrobial susceptibility and resistance mechanisms of methicillin resistant Staphylococcus aureus isolated from 12 Hospitals in Turkey.

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important nosocomial pathogens and is also emerging in Turkish hospitals. The aim of this study was to determine the antimicrobial susceptibility profiles of MRSA isolated from Turkish hospitals. MATERIALS AND METHODS: A total of 397 MRSA strains isolated from 12 hospitals in Turkey were included to present study. Antimicrobial susceptibilities were tested using agar dilution method. Presence of ermA, ermB, ermC, msrA, tetM, tetK, linA and aac-aph genes were studied by PCR. RESULTS: All strains were susceptible to vancomycin and linezolid. The susceptibility rates for fusidic acid, lincomycin, erythromycin, tetracyclin, gentamycin, kanamycin, and, ciprofloxacin were 91.9%, 41.1%, 27.2%, 11.8%, 8.5%, 8.3% and 6.8%, respectively. Lincomycin inactivation was positive for 3 isolates. Of 225 erythromycin resistant isolates 48 had ermA, 20 had ermC, and 128 had ermA-C. PCR was negative for 15 strains. Of 3 isolates with lincomycin inactivation one had linA and msrA. Of 358 gentamycin resistant isolates 334 had aac-aph and 24 were negatives. Among 350 tetracyclin resistant isolates 314 had tetM. Of 36 tetM negative isolates 10 had tetK. CONCLUSION: MRSA isolates from Turkish hospitals were multiresistant to antimicrobials. Quinolone and gentamycin resistance levels were high and macrolide and lincosamide resistance were relatively low. Susceptibility rates for fusidic asid were high. Linezolide and vancomycin resistance are not emerged. The most common resistance genes were ermA, tetM and aac-aph. Evolution of antimicrobial susceptibilities and resistance genes profiles of MRSA isolates should be surveyed at regional and national level for accurate treatment of patients and to control dissemination of resistance genes.

[t030 is the most common spa type among methicillin-resistant Staphylococcus aureus strains isolated from Turkish hospitals]. / t030, Türkiye'deki Hastanelerden Izole Edilen Metisiline Dirençli Staphylococcus aureus Izolatlari Arasinda En Yaygin spa Tipidir.

Staphylococcus aureus is one of the most frequent agents causing hospital infections. S.aureus has a great ability to adapt itself to variety of conditions and successful clones can be epidemic and even pandemic by its ability spread from one continent to another. The aims of this study were to detect spa types of 397 methicillin-resistant S.aureus (MRSA) strains isolated from 12 centers in different geographical regions of Turkey from 2006 to 2008, and to investigate their clonality by PFGE and MLST typing. Additionally, 91 MRSA from four of those 12 centers isolated during 2011 were also studied for their spa types. PFGE profiles indicated the presence of a major pulsotype, namely pulsotype A with a rate of 91.4% (363/397), followed by pulsotype B (n= 18, 4.5%) and pulsotype C (n= 11, 2.8%). Among isolates tested 363 (91.4%) were SCCmec type III, 30 (7.6%) were SCCmec type IV. Sequence analysis of representative isolates revealed that ST239 (85.1%) was the most common MLST type followed by two MLST types ST737 (4%), and ST97 (2.8%), both SCCmec type IV. Two isolates were ST80 with SCCmec type IV. Of 397 isolates, 338 (85.1%) were t030, followed by t005 (2.5%) and t632 (2%). Among MRSA isolated during 2011, 64 (70.3%) of 91 were t030, 4 (4.4%) were t005, 2 (2.2%) were t015, and 2 (2.2%) were t1094. Among centers the t030 prevalence of 2006-2008 isolates ranged from 59-100%. The highest t030 prevalence was found in Ankara (100%) and lowest in Trabzon (59%) provinces which are located at central and northestern Anatolia, respectively. In Istanbul province, the prevalence of t030 was 94.5% among 2006-2008 isolates which decreased to 55.5% among 2011 isolates. Also a decrease in t030 rates was observed among samples from Konya and Trabzon but not from Aydin. Our results showed that the most common MRSA clone in Turkey is ST 239-SCCmec type III, t030 which persisted during the six years of the study period. Presence of PVL toxin gene was tested by PCR and 5 (3%) isolates found to be positive, of them two were SCCmec Type IV-ST80 and three were SCCmec Type III-ST239. This study is the largest epidemiological survey ever done in Turkey which showed presence of a hospital Turkish clone TR09 (ST239-SCCmecIII-t030) and a community clone TR10 (ST737-SCCmecIV-t005) largely disseminated in Turkey.

[Evaluation of antibiotic susceptibilities and VISA-VRSA rates among MRSA strains isolated from hospitalized patients in intensive care units of hospitals in seven provinces of Turkey]. / Türkiye'de Yedi Ildeki Hastanelerin Yogun Bakim Ünitelerinden Izole Edilen MRSA Suslarinda VISA-VRSA Arastirilmasi ve Antibiyotik Duyarlilik Durumlarinin Saptanmasi

The aim of this study was to determine whether vancomycin resistant Staphylococcus aureus (VRSA) and vancomycin intermediate susceptible S.aureus (VISA) strains were present among methicillin-resistant S.aureus (MRSA) strains isolated from patients hospitalised at intensive care units (ICU) of hospitals located at different regions of Turkey and to determine the minimum inhibitory concentration (MIC) values of teicoplanin, linezolid, tigecycline, quinupristin-dalfopristin and daptomycin, which are alternative drugs for the treatment of MRSA infections. A total of 260 MRSA clinical strains (isolated from 113 lower respiratory tract, 90 blood, 24 wound, 17 catheter, 13 nasal swabs, two urine and one CSF sample) were collected from nine health-care centers in eight provinces [Ankara (n= 52), Konya (n= 49), Antalya (n= 40), Istanbul (n= 7), Izmir (37), Diyarbakir (n= 15), Van (n= 12), Trabzon (n= 48)] selected as representatives of the seven different geographical regions of Turkey. Methicillin resistance was determined by cefoxitin disk diffusion in the hospitals where the strains were isolated and confirmed by oxacillin salt agar screening at the Refik Saydam National Public Health Agency. Screening for VISA and VRSA was conducted using the agar screening test and E-test. Susceptibility of the MRSA strains to other antibiotics was also determined by E-test method. None of the 260 MRSA strains were determined to be VRSA or VISA. All were susceptible to teicoplanin and linezolid, and susceptibility rates to daptomycin, tigecycline and quinupristin-dalfopristin were 99.6%, 96.9%, and 95%, respectively. Absence of VISA and VRSA among the MRSA strains surveyed currently seemed hopeful, however, continuous surveillance is necessary. In order to prevent the development of VISA and VRSA strains the use of linezolid, tigecycline, quinupristin-dalfopristin and daptomycin should be encouraged as alternative agents of treatment of MRSA infections.

Does interleukin-18 play a role in the pathogenesis of hepatic encephalopathy?

BACKGROUND/AIMS: It has been suggested that the presence of inflammation may accentuate the neuropsychologic alterations in hepatic encephalopathy (HE). The aim of the study was to investigate any association between alterations in plasma levels of the pro-inflammatory cytokine IL-18 and HE. METHODOLOGY: The study population included 63 patients with cirrhosis and 20 healthy controls. Laboratory data included international normalized ratio, plasma albumin, bilirubin, urea, creatinine, hsCRP and IL-18 (pg/mL). HE was assessed using West Haven criteria and critical flicker frequency (CFF) measurement. RESULTS: Forty-two of the 63 cirrhotic patients had HE (4, 16, 21 and 1 patients in grade 0, 1, 2, 3, respectively). hsCRP and IL-18 were significantly increased in patients with HE compared with the control group (1.6 +/- 4.8 vs 0.5 +/- 0.8, p<0.001 and 121.4 (13.6-2043.6) vs 56.3 (13.0-174.0), p=0.006, respectively). The levels of hsCRP and IL-18 were significantly higher in the all cirrhotic patients than in the control subjects (p=0.002 and p=0.008 respectively). hsCRP was significantly higher in patients with HE (2.2 +/- 6) than in patients without HE (0.7 +/- 1.2) (p=0.013). The levels of IL-18 were found higher in patients with HE than in patients without HE [121.4 (13.6-2043.6) vs 103.8 (13.0-828.0)] but the difference was not significant (p=0.215). IL-18 was higher in patients with elevated hsCRP [124.6 (13.6-2043.6)] compared with those who had normal hsCRP [75.6 (13.0-753.2)] (p=0.029). CONCLUSION: There is an inflammatory response in the presence of cirrhosis and HE; and IL-18 may play a role in the perpetuation of chronic inflammation.

[Evaluation of the enrichment broth cultures in the isolation of methicillin-resistant Staphylococcus aureus]. / Metisiline dirençli Staphylococcus aureus izolasyonunda zenginlestirme buyyonu ekimlerinin degerlendirilmesi.

The detection of the methicillin-resistant Staphylococcus aureus (MRSA) carriers and the establishment of isolation precautions are of crucial importance to prevent the development of nosocomial infections due to MRSA. Previous studies have demonstrated that the use of enrichment broths increased the rate of MRSA isolation both in clinical samples and surveillance cultures. The aim of this study was to evaluate the MRSA isolation results obtained by inoculation of surveillance cultures in enrichment broth, for the patients staying in intensive care unit of our hospital during September 2006-January 2007 period. A total of 1536 samples (deep tracheal aspirate, nose, throat, pus, inguinal and axial swabs) from 250 patients were inoculated on routine primary media including sheep blood agar, EMB agar and 6 microg/ml oxacillin containing Mueller-Hinton agar (Ox-MH Agar) and also in an enrichment broth (EB) containing 6.5% NaCl in brain-heart infusion. After incubation for 24 and 48 hours, primary plates were examined for MRSA growth and enrichment broths were examined for turbidity. Turbid tubes were subcultured on Ox-MH agar. Tubes with no turbidity after 48 hours were discarded as negative; MRSA growth in both primary plates and in EBs were evaluated as "parallel growth". Parallel MRSA growth was detected in 15.2% (234/1536), MRSA growth only in EB was detected in 5.9% (91/1536) and MRSA growth only on primary plates was detected in 0.26% (4/1536) of the samples. Among the 71 patients in whom the first MRSA isolation was detected, 19 (27%) yielded MRSA only in EB, 44 (62%) exhibited parallel growth and 8 (11%) yielded MRSA either in EB or as parallel growth of different samples of the same patient. The use of the EB increased MRSA isolation 5.9% (91/1536) on specimen basis and 7.6% (19/250) on patient basis. It can be concluded that, inoculation of surveillance culture samples into an enrichment broth in addition to primary plate media aids to the early isolation of MRSA from colonized patients.

The impact of admission cystatin C levels on in-hospital and three-year mortality rates in acute decompensated heart failure.

BACKGROUND: Although tremendous advances have been made in preventative and therapeutic approaches in heart failure (HF), the hospitalisation and mortality rates for patients with HF is high. The aim of this study was to investigate the association between cystatin C and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels and in- and out-of-hospital mortality rates in acute decompensated HF (ADHF). METHODS: Between February 2008 and November 2011, 57 consecutive patients who were admitted with ADHF were included in this prospective study. These patients were clinically followed up every three months by means of visits or telephone interviews. The primary clinical endpoint of this study was any death from heart failure rehospitalisation and/or other causes. RESULTS: The subjects who died during the in-hospital follow up were younger than the survivors (47.4 ± 17.5 vs 60.8 ± 15.8, p = 0.043). There was a notable correlation between plasma cystatin C and NT-proBNP levels (r = 0.324, p = 0.014) and glomerular filtration rate (GFR) (r = -0.638, p < 0.001). Multivariate logistic regression analysis revealed that only cystatin C level [odds ratio (OR): 12.311, 95% confidence interval (CI): 1.616-93.764, p = 0.015] and age [OR: 0.925, 95% CI: 0.866-0.990, p = 0.023] were linked to in-hospital mortality rate. In the multivariate Cox proportional hazard model, only admission sodium level appeared as a significant independent predictor of death during the 36-month follow up [hazard ratio: 0.937, 95% CI: 0.880-0.996, p = 0.037]. CONCLUSION: Evaluation of admission cystatin C levels may provide a reliable prediction of in-hospital mortality, compared to estimated GFR or NT-proBNP levels among patients with ADHF. However, in this trial, during long-term follow up, only admission sodium level significantly predicted death.

[Short communication: comparison of susceptibilities of Escherichia coli urinary tract isolates against fosfomycin tromethamine and different antibiotics]. / Kisa bildiri: uriner sistem Escherichia coli izolatlarinin fosfomisin trometamol ve çeçiti antibiyotiklere karsi duyarliliklarinin karsilastirilmasi.

The aim of this study was to investigate the susceptibilities of Escherichia coli strains isolated from urine samples, against fosfomycin tromethamine and different antibiotics in the period of October-December 2004 in a local hospital in Ankara, Turkey. A total of 120 E. coli strains isolated from urine cultures of subjects who were admitted to outpatient clinics were included to the study. The identification and antimicrobial susceptibility tests (against amikacin, amoxicillin/clavulanate, ampicillin, cefepime, cefoxitin, cefotaxime, cefuroxime, cefalotin, ciprofloxacin, gentamicin, levofloxacin, meropenem, nitrofurantoin, piperacillin, piperacillin/tazobactam and trimethoprim/sulphametoxazole) were performed by a commercial automatized system (Phoenix, Becton Dickinson, USA). Fosfomycin tromethamine susceptibility was studied by Kirby Bauer disk diffusion method according to the CLSI criteria. Only one strain (0.8%) was found resistant to fosfomycin tromethamine, while no resistance was determined against amikacin and meropenem. Most of the isolates were found susceptible to nitrofurantoin (90%), cefoxitin (82.5%), gentamicin (81%), piperacillin/tazobactam (81%), cefepime (79%) and cefotaxime (%79%). All of the E. coli isolates which were resistant to ciprofloxacin and levofloxacin (44% and 43%, respectively) were found susceptible to fosfomycin tromethamine. In conclusion, since E. coli is by far the most prevalent community acquired urinary tract pathogen, fosfomycin tromethamine seems to be a reasonable alternative for the ampirical therapy of uncomplicated urinary tract infections.

Pan-resistant Acinetobacter baumannii mediastinitis treated successfully with tigecycline: a case report.

BACKGROUND: Mediastinitis due to Acinetobacter baumannii is rare. METHODS: We report a case of mediastinitis caused by pan-resistant A. baumannii in a patient with multiple comorbidities who underwent cardiopulmonary bypass and we also present a literature review. RESULTS: Successful treatment consisted of surgical debridement plus drainage, and tigecycline administration for three weeks. CONCLUSION: Surgical source control along with effective antibiotics is essential in the treatment of mediastinitis. Tigecycline has the potential to be an option for pan-resistant A. baumannii mediastinitis.