Person: KORTEN, VOLKAN
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KORTEN
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VOLKAN
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Publication Open Access A rare Case of otitis media-associated polymicrobial anaerobic meningitis and brain abscess(2021-12-01) ERTÜRK ŞENGEL, BUKET; TİGEN, ELİF; OLUÇ, YUSUF; ÜLGER, NURVER; KORTEN, VOLKAN; ERTÜRK ŞENGEL B., TİGEN E., YILDIZ F., OLUÇ Y., ÜLGER N., KORTEN V.Otitis media-associated complications are widespread when it is not treated with appropriate antimicrobial treatment. Meningitis and brain abscess are the most reported intracranial complications of otitis media, usually caused by the direct spread of organisms from the contagious site. While anaerobic microorganisms are well-known in brain abscesses, they are not common in meningitis. When the clinical history and pathogenesis of otitis mediaassociated meningitis are combined, special methods to identify and cover anaerobic pathogens should be consideredPublication Open Access An outbreak investigation of Burkholderia cepacia infections related with contaminated chlorhexidine mouthwash solution in a tertiary care center in Turkey(BMC, 2021-12) GÜL, FETHİ; Bilgin, Huseyin; Gelmez, Gulsen Altinkanat; Bayrakdar, Fatma; Sayin, Elvan; Gul, Fethi; Pazar, Nazli; Culha, Gulcan; Yildiz, Serap Suzuk; Cinel, Ismail; Korten, VolkanBackground: We report a nosocomial outbreak caused by Burkholderia cepacia that occurred among six patients admitted in the medical and surgical intensive care unit between 04 March 2019 and 02 April 2019 in Istanbul, Turkey. Methods: The outbreak investigation was launched on 11 March 2019 five days after the detection of B. cepacia in four different patients. We defined potential reservoirs and started environmental screening. We sampled the liquid solutions used in patient care activities. Pulse-field gel electrophoresis (PFGE) was performed to determine the genetic relatedness of environmental and patient samples. Results: Burkholderia cepacia was isolated in tracheal aspiration cultures of six patients. Three out of six patients developed healthcare-associated pneumoniae due to B. cepacia. Environmental cultures in the ICUs revealed B. cepacia growth in 2% chlorhexidine-gluconate mouthwash solution that been used in the colonized patients as well as in samples obtained from the unused products. PFGE revealed the patient and a specific batch of chlorhexidine mouthwash solution samples had a 96% similarity. Conclusion: Contamination of medical solutions used in critical patient care could cause outbreaks and should be detected early by infection control teams.Publication Open Access Diagnostic performance between RT-PCR and chest CT in outpatients with clinically suspected COVID-19(2023-08-01) TİGEN, ELİF; ERTÜRK ŞENGEL, BUKET; ÇİMŞİT, CANAN; APAYDIN KAYA, MEMNUNE ÇİĞDEM; KORTEN, VOLKAN; TİGEN E., ERTÜRK ŞENGEL B., ÇİMŞİT C., PERK GURUN H., APAYDIN KAYA M. Ç., KORTEN V.Objective: To investigate the diagnostic performance between chest computed tomography (CT) and reverse transcription-polymerase chain reaction (RT-PCR) in outpatients with suspected coronavirus disease 2019 (COVID-19). Patients and Methods: Between March and June 2020, a total of 812 patients with clinically suspected COVID-19 who underwent both chest CT and initial-single RT-PCR on admission to outpatient units were retrospectively enrolled. CT severity-score (CT-SS) was calculated and data were matched with PCR results. Results: Of 812 patients, 54% (439/812) had positive RT-PCR results, and 47% (425/812) had a positive chest CT scan. With RT-PCR results as reference, the sensitivity, specificity, accuracy of chest CT in defining COVID-19 infection were 60%, (95% CI 56-65%, 265/439 patients), 57% (95% CI 52-62%, 213/373), 59% (95% CI 55-62%, 478/812), respectively. Three hundred eighty-seven (47%) patients had no CT findings, 380/812 (46.8%) had mild, 45/812 (5.5%) had moderate, and no patients in the severe group Conclusion: Chest CT did not show high sensitivity for the diagnosis of COVID-19 for outpatients. We suggest RT-PCR should be the primary diagnostic tool. Chest CT might be considered if there is a strong clinical suspicion with repeatedly negative RT-PCR test results, ensuring infection prevention and control measures can be preserved.Publication Metadata only 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.Publication Open Access ISARIC-COVID-19 dataset: A Prospective, standardized, global dataset of patients hospitalized with COVID-19(2022-07-30) KORTEN, VOLKAN; Garcia-Gallo E., Merson L., Kennon K., Kelly S., Citarella B. W. , Fryer D. V. , Shrapnel S., Lee J., Duque S., Fuentes Y. V. , et al.© The Author(s) 2022.The International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) COVID-19 dataset is one of the largest international databases of prospectively collected clinical data on people hospitalized with COVID-19. This dataset was compiled during the COVID-19 pandemic by a network of hospitals that collect data using the ISARIC-World Health Organization Clinical Characterization Protocol and data tools. The database includes data from more than 705,000 patients, collected in more than 60 countries and 1,500 centres worldwide. Patient data are available from acute hospital admissions with COVID-19 and outpatient follow-ups. The data include signs and symptoms, pre-existing comorbidities, vital signs, chronic and acute treatments, complications, dates of hospitalization and discharge, mortality, viral strains, vaccination status, and other data. Here, we present the dataset characteristics, explain its architecture and how to gain access, and provide tools to facilitate its use.Publication Open Access Transmission of SARS-CoV-2 in Different Districts of a County in Istanbul, March to September 2020(SAGE PUBLICATIONS INC, 2021-07) TOPUZOĞLU, AHMET; Bilgin, Huseyin; Topuzoglu, Ahmet; Korten, VolkanEpidemics caused by airborne viruses in cities with large populations create a big problem as in the current COVID-19 pandemic. Cramped lifestyle, busy workplaces, crowded public transportation, and higher household member counts are responsible for the transmission of the disease. In Turkey, Istanbul has taken the lead in the number of cases since the beginning of the epidemic. The excess population density is the major cause for disease transmission. It is essential to monitor the contaminated regions with geographical information systems on city maps. Outbreak maps visualize and help analyze the patterns of transmission and serve as a communication and education tool. A dynamic heat map video of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) polymerase chain reaction positive cases in a county of Istanbul was generated. The heat map visualizes how the epidemic spread to all the districts and the cumulative cases increased in one county of Istanbul with real attack rates.Publication Open Access Marmara Üniversitesi Pendik Eğitim ve ID_x000D_ Araştırma Hastanesi’nde 2014-2018 Yılları_x000D_ Arasındaki Kronik Hepatit C Prevalansı,_x000D_ Genotip Dağılımı ve Tedavi Yanıtları(2020) ERTÜRK ŞENGEL, BUKET; Betül ERTÜRK ŞENGEL;Tuğçe BAŞARI;Elif TÜKENMEZ TİGEN;Rabia CAN SARINOĞLU;Barış CAN;ULUHAN SİLİ;Volkan KORTENHepatit C dünyada yaygın olarak görülen ve mortaliteye neden olabilen ciddi bir hastalıktır.Bu çalışmada Marmara Üniversitesi Pendik Eğitim ve Araştırma Hastanesi’nebaşvuran hastalarda anti-HCV seropozitiflik sıklığının ve kronik viral hepatit C (HCV)tanısı konarak tedavi verilen hastaların genotip dağılımları ile tedavi başarılarınındeğerlendirilmesi amaçlanmıştır. Çalışmada retrospektif olarak Ocak 2014-Aralık 2018tarihleri arasında anti-HCV istemi yapılan serum örnekleri taranmıştır. Reaktif bulunanörneklerin HCV RNA pozitiflikleri ile genotip dağılımları ve kronik HCV tanısı ile tedaviverilen hastaların kalıcı viral yanıt başarı oranları değerlendirilmiştir. Total 76,413 hastadan100,100 serum örneğinde anti-HCV istemi yapılmış ve 1,808 (% 2,36) hastadapozitif bulunmuştur. Bu hastaların 1,286’sında (% 71) HCV RNA bakılmış ve 291 (% 23)hastada pozitif saptanmıştır. HCV RNA tespit edilen hastalarda 129’una (% 44) hastanemizdekronik HCV tanısı ile tedavi verilmiştir. En sık genotip 1b saptanmış olup, tedavisonrası 24’üncü haftada kalıcı viral yanıt hastaların % 87’sinde elde edilmiştir. Sonuçolarak antiviral tedavi ile virolojik başarı oranları yüz güldürücü olsa da halen tanı vetedavi alması gereken ancak tespit edilemeyen hasta sayısı da oldukça yüksektir.Publication Open Access Trends and factors associated with modification or discontinuation of the initial antiretroviral regimen during the first year of treatment in the Turkish HIV-TR Cohort, 2011-2017(BMC, 2021-12) KORTEN, VOLKAN; Korten, Volkan; Gokengin, Deniz; Eren, Gulhan; Yildirmak, Taner; Gencer, Serap; Eraksoy, Haluk; Inan, Dilara; Kaptan, Figen; Dokuzoguz, Basak; Karaoglan, Ilkay; Willke, Ayse; Gonen, Mehmet; Ergonul, OnderBackground: There is limited evidence on the modification or stopping of antiretroviral therapy (ART) regimens, including novel antiretroviral drugs. The aim of this study was to evaluate the discontinuation of first ART before and after the availability of better tolerated and less complex regimens by comparing the frequency, reasons and associations with patient characteristics. Methods: A total of 3019 ART-naive patients registered in the HIV-TR cohort who started ART between Jan 2011 and Feb 2017 were studied. Only the first modification within the first year of treatment for each patient was included in the analyses. Reasons were classified as listed in the coded form in the web-based database. Cumulative incidences were analysed using competing risk function and factors associated with discontinuation of the ART regimen were examined using Cox proportional hazards models and Fine-Gray competing risk regression models. Results: The initial ART regimen was discontinued in 351 out of 3019 eligible patients (11.6%) within the first year. The main reason for discontinuation was intolerance/toxicity (45.0%), followed by treatment simplification (9.7%), patient willingness (7.4%), poor compliance (7.1%), prevention of future toxicities (6.0%), virologic failure (5.4%), and provider preference (5.4%). Non-nucleoside reverse transcriptase inhibitor (NNRTI)-based (aHR = 4.4, [95% CI 3.0-6.4]; p < 0.0001) or protease inhibitor (PI)-based regimens (aHR = 4.3, [95% CI 3.1-6.0]; p < 0.0001) relative to integrase strand transfer inhibitor (InSTI)-based regimens were significantly associated with ART discontinuation. ART initiated at a later period (2015-Feb 2017) (aHR = 0.6, [95% CI 0.4-0.9]; p < 0.0001) was less likely to be discontinued. A lower rate of treatment discontinuation for intolerance/toxicity was observed with InSTI-based regimens (2.0%) than with NNRTI- (6.6%) and PI-based regimens (7.5%) (p < 0.001). The percentage of patients who achieved HIV RNA < 200 copies/mL within 12 months of ART initiation was 91% in the ART discontinued group vs. 94% in the continued group (p > 0.05). Conclusion: ART discontinuation due to intolerance/toxicity and virologic failure decreased over time. InSTI-based regimens were less likely to be discontinued than PI- and NNRTI-based ART.Publication Metadata only 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.Publication Metadata only 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.