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KORTEN, VOLKAN

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    Susceptibility of bacterial isolates from Turkey - A report from the Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) Program
    (TAYLOR & FRANCIS LTD, 2007) KORTEN, VOLKAN; Eraksoy, H.; Basustaoglu, A.; Korten, V.; Kurt, H.; Ozturk, R.; Ulusoy, S.; Yaman, A.; Yuce, A.; Zarakolu, P.
    The study monitored the susceptibility of nosocomial pathogens to meropenem and comparator antimicrobial agents isolated as part of the Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) Program from Turkish university hospitals. In terms of minimum inhibitory concentration 90% (MIC90) values, meropenem was two- and eight-fold more active than imipenem against Escherichia coli and Klebsiella pneumoniae, respectively. 40.5% of K. pneumoniae, 23.1% of Klebsiella oxytoca and 15.3% of E. coli isolates were extended-spectrum P-lactamase (ESBL) producers. Piperacillin/tazobactam was the most active agent against isolates of Pseudomonas aeruginosa, followed by meropenem and imipenem. Against Acinetobacter baumannii isolates, meropenem and imipenem were the most active agents. Continued surveillance by the MYSTIC Program appears to be prudent to help focus on effective empiric treatment regimens.
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    COVID-19 tanısı ile antikoagulasyon altında gelişeninfekte retroperitoneal hematom
    (2021-05-26) ERTÜRK ŞENGEL, BUKET; KORTEN, VOLKAN; Marku M., ERTÜRK ŞENGEL B., Çolak G. M. , KORTEN V.
    Amaç C.auris sağlık bakımı ilişkili infeksiyonlara neden olan, birçok antifungale dirençli son derece virülan bir mantardır. Sağlık merkezlerinde salgınlara neden olduğundan erken tanı konulması gerekli önlemlerin alınması bakımından çok önemlidir. Ancak standart laboratuvar teknikleri ile tanımlanması zordur ve spesifik yöntemler kullanılmazsa yanlış tanımlanabilir. Bu yazı COVID-19 tanısı ile yoğun bakımında yatmakta olan hastalarda nadir ve infeksiyon kontrol açısından büyük risk oluşturan C.auris üremelerini anlatmaktadır. Olgular Hastaların demografik ve klinik özellikleri Tablo 1’de özetlenmiştir. Tüm hastaların 60 yaşın üzerinde olması, öncesinde geniş spektrumlu antibiyotik ve steroid kullanım öyküleri olması dikkat çekmektedir. İntrakranial kanama nedeniyle opere edilen Olgu 1’in yara yeri ve Olgu 2’nin ise genital bölge sürüntüsünde C.auris üremesi olmuştur ve etken olarak kabul edilmemişlerdir. Olgu 5’in ise inguinal bölge sürüntü kültürlerinin yanı sıra periferik kan ve idrar kateter kültürlerinde de üreme olduğundan etken olarak kabul edilmiştir. Hastalara ait klinik örneklerden üretilmiş maya kolonileri MALDI-TOF MS (VITEK MS, V3.0, BioMérieux) kullanılarak % 99.9 identifikasyon skoru oranlarıyla C.auris olarak tanımlanmıştır. Olgu 4 halen yatmakta olup diğer tüm hastalar kaybedilmiştir. Sonuç Ülkemizde şimdiye kadar C.auris ile infekte olgu raporlanmamıştır. C. auris üremeleri, COVID-19 nedeniyle yoğun bakım yatışlarının uzaması, COVID-19 seyrinde kullanılan immunsupresif tedaviler ve geniş spektrumlu antibiyotik kullanımları gibi faktörlere bağlı olabilir. Etkenin doğru tanınması ve tedavinin erken başlanması mortalite açısından çok önemlidir. Olgularımız hem COVID-19 hastalarında hem de Türkiye’de bildirilen ilk C.auris vakaları olması nedeniyle dikkat çekici özellik taşımaktadır.
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    Surveillance, control and management of infections in intensive care units in Southern Europe, Turkey and Iran - A prospective multicenter point prevalence study
    (W B SAUNDERS CO LTD, 2014) KORTEN, VOLKAN; Erdem, Hakan; Inan, Asuman; Altindis, Selma; Carevic, Biljana; Askarian, Mehrdad; Cottle, Lucy; Beovic, Bojana; Csomos, Akos; Metodiev, Krassimir; Ahmetagic, Sead; Harxhi, Arjan; Raka, Lul; Grozdanovski, Krsto; Nechifor, Mihai; Alp, Emine; Bozkurt, Fatma; Hosoglu, Salih; Balik, Ismail; Yilmaz, Gulden; Jereb, Matjaz; Moradi, Fatemeh; Petrov, Nikolay; Kaya, Selcuk; Koksal, Iftihar; Aslan, Turan; Elaldi, Nazif; Akkoyunlu, Yasemin; Moravveji, Seyyed Alireza; Csato, Gabor; Szedlak, Balazs; Akata, Filiz; Oncu, Serkan; Grgic, Svjetlana; Cosic, Gorana; Stefanov, Chavdar; Farrokhnia, Mehrdad; Mueller, Maria; Luca, Catalina; Koluder, Nada; Korten, Volkan; Platikanov, Viliyan; Ivanova, Petja; Soltanipour, Soheil; Vakili, Mahmood; Farahangiz, Saman; Afkhamzadeh, Abdorrahim; Beeching, Nicholas; Ahmed, Salman Shaheer; Cami, Alma; Shiraly, Ramin; Jazbec, Anja; Mirkovic, Tomislav; Leblebicioglu, Hakan; Naber, Kurt
    Objective: We aimed to compare the features of intensive care units (ICUs), their antimicrobial resistance patterns, infection control policies, and distribution of infectious diseases from central Europe to Mid-West Asia. Methods: A cross-sectional point prevalence study was performed in 88 ICUs from 12 countries. Characteristics of ICUs, patient and antibiotic therapy data were collected with a standard form by infectious diseases specialists. Results: Out of 749, 305 patients at least with one infectious disease were assessed and 254 patients were reported to have coexistent medical problems. When primary infectious diseases diagnoses of the patients were evaluated, 69 had community-acquired, 61 had healthcare-associated, and 176 had hospital-acquired infections. Pneumonia was the most frequent ICU infection seen in half of the patients. Distribution of frequent pathogens was as follows: Enteric Gram-negatives (n = 62, 28.8%), Acinetobacter spp. (n = 47, 21.9%), Pseudomonas aeruginosa (n = 29, 13.5%). Multidrug resistance profiles of the infecting microorganisms seem to have a uniform pattern throughout Southern Europe and Turkey. On the other hand, active and device-associated infection surveillance was performed in Turkey more than Iran and Southeastern Europe (p < 0.05). However, designing antibiotic treatment according to culture results was highest in Southeastern Europe (p < 0.05). The most frequently used antibiotics were carbapenems (n = 92, 30.2%), followed by anti-gram positive agents (vancomycin, teicoplanin, linezolid, daptomycin, and tigecycline; n = 79, 25.9%), beta-lactam/beta lactamase inhibitors (n = 78, 25.6%), and extended-spectrum cephalosporins (n = 73, 23.9%). Conclusion: ICU features appears to have similar characteristics from the infectious diseases perspective, although variability seems to exist in this large geographical area. (C) 2013 The British Infection Association. Published by Elsevier Ltd. All rights reserved.
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    Outcomes of Fecal Carriage of Extended-spectrum beta-Lactamase After Transrectal Ultrasound-guided Biopsy of the Prostate
    (ELSEVIER SCIENCE INC, 2014) ERTÜRK ŞENGEL, BUKET; Tigen, Elif Tukenmez; Tandogdu, Zafer; Ergonul, Onder; Altinkanat, Gulsen; Gunaydin, Bilal; Ozgen, Mahir; Sariguzel, Nevin; Sengel, Buket Erturk; Odabasi, Zekaver; Cek, Mete; Tokuc, Resit; Turkeri, Levent; Mulazimoglu, Lutfiye; Korten, Volkan
    OBJECTIVE To determine the prevalence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae (PE) fecal carriage in patients that undergo transrectal ultrasonography-guided biopsy (TRUSbx) and its relationship with post-biopsy infections. METHODS A prospective clinical study in 4 different tertiary hospitals between 2008 and 2010 was conducted. Four hundred men with sterile urine who were to undergo a TRUSbx because of the suspicion of prostate cancer were included and followed for 14 days after biopsy. Rectal swab culture specimens were acquired immediately before the procedure. Demographic data, prophylaxis choice, quinolone or any other antibiotic consumption within the past 2 months, history of prostatitis, repeat biopsy, intensive care unit admission, hospitalization, urethral catheterization, diabetes mellitus (DM), and steroid usage were recorded. RESULTS ESBL carriage was detected in 19% of patients and quinolone use within the last 2 months; other antibiotic use within the last 2 months and DM were found to be significantly associated (P < .05). Symptomatic urinary tract infection (UTI) on the third day after biopsy was seen in 9% of patients and was associated with fluoroquinolone (FQ) consumption before biopsy. Although ESBL-PE carriage was associated with post-biopsy UTI symptoms, it was not found to be associated with post-biopsy symptomatic UTI. Urosepsis was seen in 2 patients (0.5%) after biopsy, and both the patients were ESBL-PE carriers. CONCLUSION The presence of ESBL-PE was associated with DM and FQ consumption before biopsy. ESBL-PE carriage was associated with a high rate of post-biopsy UTI symptoms requiring further elucidation; however, it was not associated with microbiologically proven infections. FQ consumption before TRUSbx was also associated with post-biopsy infections. (C) 2014 Elsevier Inc.
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    Antibiotic resistance surveillance over a 4-year period (2000-2003) in Turkey: results of the MYSTIC Program
    (ELSEVIER SCIENCE INC, 2007) KORTEN, VOLKAN; Korten, Volkan; Ulusoy, Sercan; Zarakolu, Pinar; Mete, Birgul
    The Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) Program is a global study that provides antimicrobial susceptibility data in centers prescribing meropenem. The activity of meropenem and 7 broad-spectrum antimicrobials have been examined against 5208 bacterial isolates from 9 Turkish centers between 2000 and 2003. Cumulative susceptibility rates against all species of Enterobacteriaceae combined were ranked as follows: meropenem (99.3%), imipenem (97.6%), cefepime (80.0%), piperacillin-tazobactam (73.6%), ceftazidime (70.3%), ciprofloxacin (70.1%), cefotaxime (66.9%), and tobramycin (67.2%). The production of extended-spectrum beta-lactamases (ESBLs) was detected in 48.7% of Klebsiella pneumoniae and in 19.5% of Escherichia coli isolates. Of ESBL producing K. pneumoniae isolates, 75.7% were resistant to tobramycin, 40.3% to ciprofloxacin, and 48.3% to piperacillin-tazobactam. Only piperacillin/ tazobactam and carbapenems were active against more than 50% of Pseudomonas aeruginosa at the National Committee for Clinical Laboratory Standards-susceptible breakpoint, and the carbapenems were the most active compounds against Acinetobacter spp. These data confirm the continued potency of meropenem against Enterobacteriaceae in units where it is actively being prescribed. (c) 2007 Elsevier Inc. All rights reserved.
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    Prevalence of HIV-associated neurocognitive disorder (HAND) in Turkey and assessment of Addenbrooke's Cognitive Examination Revised (ACE-R) test as a screening tool
    (WILEY, 2021) TİGEN, ELİF; Korten, V; Ay, U.; Hari, E.; Tigen Tukenmez, E.; Gencer, S.; Akca Kalem, S.; Demirtas Tatlidede, A.; Gurvit, I. H.
    Objectives We aimed to assess the Addenbrooke's Cognitive Examination Revised (ACE-R) and three questions (3Qs, European Aids Clinical Society Guidelines) as potential screening tools for HIV-associated neurocognitive disorder (HAND). In addition, we tried to determine the prevalence and associated factors for HAND among people living with HIV (PLWH) in Turkey. Methods Persons living with HIV were enrolled from two teaching hospitals between March 2018 and September 2018. Participants underwent screening tools, a neuropsychological test battery (NTB) and an assessment of activities of daily living. HAND was diagnosed according to Frascati's criteria and applying the Global Deficit Score (GDS) approach. A receiver operating characteristic (ROC) curve analysis was performed to compare the predictive accuracy of ACE-R to that of the NP test battery. Factors associated with HAND were evaluated using multivariate logistic regression analysis. Results The study sample included 162 participants (94% male). The HAND prevalence was 45.7% [asymptomatic neurocognitive impairment (ANI), 37.7%; mild neurocognitive disorder (MND), 7.4%; HIV-associated dementia (HAD), 0.6%] according to the Frascati criteria and 31.5% (ANI, 25.9%; MND, 4.9%; HAD, 0.6%) using the GDS. In the ROC analysis, the ACE-R showed an area under the curve of 0.68 at a cut-off score of 89. The sensitivity, specificity and correct classification rate of screening tests for HAND diagnosis were as follows: ACE-R (62.2%, 67%, 64.8%) and 3Qs (10.8%, 88.6%, 53%). In multivariate analysis, only education level (adjusted odds ratio [aOR] = 0.84, 95% CI: 0.76-0.92,P <= 0.001) was an independent risk factor for HAND. Conclusions HAND is a common comorbidity in PLWH in Turkey. The sensitivities and specificities of 3Qs and the ACE-R as screening tools are lower than desired.
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    Influence of oral glycopeptides on the fecal flora of human volunteers: Selection of highly glycopeptide-resistant enterococci
    (Oxford University Press, 1996) KORTEN, VOLKAN; Van Der Auwera P., Pensart N., Korten V., Murray B.E., Leclercq R.
    Changes in fecal flora were evaluated in 22 healthy volunteers administered oral vancomycin or teicoplanin in 1989-1991 in Belgium. Evaluation of 5 colonies per subject revealed no glycopeptide-resistant enterococci in the predominant flora before glycopeptide administration; however, large numbers (mostly Enterococcus faecium) emerged by the end of the study in 14 (64%) of the subjects. Pediococci and lactobacilli also increased in number. In 1992, 40 healthy volunteers and 33 cancer patients were evaluated by plating stool samples directly onto selective media containing vancomyein; low numbers of vancomycin-resistant enterococci (<50 cfu/g) were found in 11 (28%) of the 40 and 4 (12%) of the 33 samples, respectively. DNA restriction fragment length polymorphism analysis showed that most isolates were different, but all contained vanA in Tn1546-like elements. These results indicate that vanA and Tn1546-like elements were common in Belgium as early as 1989 and that community-based individuals in that location likely form a major reservoir for glycopeptide-resistant enterococci.
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    Kandan izole edilen çok ilaca dirençli escherichia coli, klebsiella pneumoniae ve pseudomonas aeruginosa kökenlerinde meropenem-vaborbaktamın etkinliğinin diğer Antibiyotiklerle karşılaştırmalı olarak araştırılması: çok merkezli çalışma
    (2022-11-16) GÜNEŞER, DENİZ; HASDEMİR GÖKBOĞA, MÜNEVVER UFUK; KORTEN, VOLKAN; ALTINKANAT GELMEZ, GÜLŞEN; Altınkanat Gelmez G., Güneşer D., Hasdemir Gökboğa M. U. , Korten V., Sağıroğlu P., Hazırolan G., Gür D., Öktem İ. M. A. , Aygün G.
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    Rectal colonization with multidrug-resistant gram-negative bacteria in patients with hematological malignancies: a prospective study
    (TAYLOR & FRANCIS LTD, 2020) TİGEN, ELİF; Komurcu, Burak; Tukenmez Tigen, Elif; Toptas, Tayfur; Firatli Tuglular, Tulin; Korten, Volkan
    Objectives To investigate the risk factors for rectal colonization with carbapenem-resistantEnterobacteriaceae(CRE) and extended-spectrum ss-lactamase-producingEnterobacteriaceae(ESBL-E) in hematological malignant patients with febrile neutropenia (FN); rate of rectal colonization and infection/colonization with CRE and ESBL-E; whether empirical treatment can be revised. Methods Adult patients receiving chemotherapy were included. Rectal swab cultures of patients were screened for CRE and ESBL-E using selective chromogenic agars. Results Fifty-seven FN episodes of 57 patients were studied. Rectal colonization rates were 40.4% (23/57) and 8.8% (5/57) for ESBL-E and CRE, respectively. ESBL-E bacteremia was diagnosed in 2 (8.6%) ESBL-E colonized patients, while CRE bacteremia was detected in 1 (20%) CRE colonized patient. Amikacin (100%) and carbapenem (93%) were the most effective antibiotics against gram-negative enteric bacteria. Beta-lactam usage within the last 3 months was a significant risk factor for ESBL-E colonization. Conclusions For the treatment of FN patients either colonized with ESBL-E or having significant risk factors for ESBL-E infection, aminoglycoside containing combinations may become an alternative to carbapenems due to their high sensitivity rates. When CRE colonized hematological cancer patients develop FN or if they are hemodynamically unstable, CRE covering empiric antibiotherapy should be preferred due to high mortality rates of CRE bacteremia.