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Dive into the research topics where Tansu Yamazhan is active.

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Featured researches published by Tansu Yamazhan.


International Journal of Antimicrobial Agents | 2012

Nitrofurantoin in the treatment of extended-spectrum β-lactamase-producing Escherichia coli-related lower urinary tract infection.

Meltem Tasbakan; Hüsnü Pullukçu; Oguz Resat Sipahi; Tansu Yamazhan; Sercan Ulusoy

The aim of this study was to evaluate the effect of nitrofurantoin (NFT) in the treatment of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli-related lower urinary tract infection (LUTI). The hospital records of all patients aged >18 years with dysuria or problems with frequency or urgency in passing urine, >20 leukocytes/mm(3) in urine microscopy and culture-proven ESBL-producing NFT-sensitive E. coli in the urine (>10(5) CFU/mm(3)), no leukocytosis or fever and who were treated with NFT between January 2006 and May 2011 in our outpatient clinic or in the hospital were evaluated. All patients had received a NFT 50 mg capsule every 6 h for 14 days and had a control urine culture taken 7-9 days after therapy. Clinical success was defined as resolution of symptoms at the control visit, and microbiological success was defined as a sterile control urine culture. A total of 75 patients (mean±standard deviation age, 54±17 years; 45 females, 30 males, all but 14 with complicated LUTI) fulfilled the study inclusion criteria. Overall clinical and microbiological success rates were 69% (52/75) and 68% (51/75), respectively. Control urine culture performed 28-31 days after the end of therapy was available in 31/51 patients (61%) with microbiological success. Re-infection and relapse rates were 6.5% (2/31) and 3.2% (1/31), respectively. In conclusion, these results suggest that NFT may be an alternative in the treatment of ESBL-producing E. coli-related LUTI. This is the first study in which NFT was used in the treatment of LUTI due to ESBL-producing E. coli as well as in patients with complicated UTI.


Journal of Chemotherapy | 2010

Carbapenem Versus Fosfomycin Tromethanol in the Treatment of Extended-Spectrum Beta-Lactamase-Producing Escherichia Coli-Related Complicated Lower Urinary Tract Infection

Sebnem Senol; Meltem Tasbakan; Hüsnü Pullukçu; Sipahi Or; Hilal Sipahi; Tansu Yamazhan; Bilgin Arda; Sercan Ulusoy

Abstract The aim of this observational prospective study was to compare the effect of fosfomycin tromethanol (FT) and carbapenems (meropenem or imipenem cilastatin) in the treatment of extended-spectrum beta-lactamase (ESBL)- producing Escherichia coli-related complicated lower urinary tract infection (CLUTI). Inclusion criteria were: patients who were aged >18 yr with dysuria or problems with frequency or urgency in passing urine; those with >20 leukocytes/mm3 in urine microscopy and culture-proven ESBL-producing carbapenem or FT-sensitive E. coli in the urine (>105 cfu/mm3); no leukocytosis or fever; and who were treated with FT (oral 3 g sachet × 1 every other night, three times) or carbapenems between march 2005 and January 2006 in our outpatient clinic and hospital. A total of 47 CLUTI attacks in 47 patients (27 FT group, 20 carbapenem group) were observed prospectively. Clinical and microbiological success in the carbapenem and FT groups was similar (19/20 vs 21/27 and 16/20 vs 16/27 p>0.05). Drug acquisition costs were significantly lower in the FT group (p<0.001). Although it is not a randomized controlled study, these data show that FT may be a suitable, effective and cheap alternative in the treatment of ESBL-producing E. coli-related CLUTI.


Tropical Doctor | 2003

Brucellosis: a retrospective evaluation.

Meltem Tasbakan; Tansu Yamazhan; Deniz Gökengin; Bilgin Arda; Mahmut Sertpolat; Sercan Ulusoy; Ekin Ertem; Demir Serter

One hundred and sixty-six presumed brucellosis patients were included in the study. These patients were classified as primary (91), relapse (18) and suspected (57) cases according to their clinical presentations, and serologic and microbiologic test results. Primary and relapse cases were evaluated retrospectively according to age, sex, residence, routes of transmission, clinical and laboratory findings, treatment regimens, duration of treatment, and relapse rates. Of the 109 primary and relapse patients, 57 were male and 52 female. The ages of the patients ranged between 16–75 (mean age 40.2). The percentages of the urban and rural residence of the patients were 41.3% and 58.7%, respectively. The most common mode of transmission was consumption of unpasteurized milk and milk products (67.9%). Malaise, fever and sweating were the most frequently observed symptoms (96.3%, 95.4%, 91.7%, respectively). The most common signs were fever (97.2%), splenomegaly (59.6%), and hepatomegaly (37.6%). The liver was the most frequently involved organ (21.1%). Almost all (99.1%) patients were serologically positive. However, the positivity rate of culture was low (15.6%). The most frequently preferred antimicrobial regimen was rifampin and doxycycline combination. The relapse rate was 8.3%. Brucellosis is still prevalent in Turkey as in many other countries in the Mediterranean basin. The clinical presentation of the disease may show regional variations. Patients with a history of occupational or nutritional contact with the bacterium and with a compatible clinical picture should be examined using appropriate diagnostic techniques before any attempt to prescribe an antimicrobial.


Journal of Antimicrobial Chemotherapy | 2008

Moxifloxacin versus ampicillin + gentamicin in the therapy of experimental Listeria monocytogenes meningitis

Oguz Resat Sipahi; Tuncer Turhan; Hüsnü Pullukçu; Sebnem Calik; Meltem Tasbakan; Hilal Sipahi; Bilgin Arda; Tansu Yamazhan; Sercan Ulusoy

OBJECTIVES This study aimed to compare the antibacterial activity of moxifloxacin and ampicillin + gentamicin in the treatment of Listeria monocytogenes meningitis in a rabbit meningitis model. METHODS Meningitis was induced by direct inoculation of a clinical strain isolated from an immunocompromised patient (10(7) cfu/mL) into the cisterna magna of New Zealand rabbits. After 16 h of incubation, rabbits were separated into four groups: moxifloxacin (M), ampicillin + gentamicin (A), ampicillin + gentamicin 2 (A2) and control (C). Group M received 20 mg/kg moxifloxacin at the end of the incubation time and 5 h later by intravenous (i.v.) route. Group A received ampicillin (30 mg/kg/h) and gentamicin (2.5 mg/kg/h) by i.v. route with continuous infusion for 8 h in 36 mL of 0.9% NaCl, group A2 received the same dosage of gentamicin and ampicillin in two different 36 mL 0.9% NaCl solutions and group C did not receive any treatment. Cerebrospinal fluid (CSF) samples (0.1-0.25 mL) were obtained 16 and 24 h after induction of meningitis. RESULTS At the end of the 16 h of incubation, CSF bacterial counts were similar in all groups (P > 0.05). At the final stage of the study (24 h after induction of meningitis), bacterial counts in all treatment groups were significantly lower than the control group (P < 0.05). When the three treatment groups were compared, bacterial counts were found to be similar (P > 0.05). CONCLUSIONS These data suggest that antibacterial activity of moxifloxacin is similar to ampicillin + gentamicin in the treatment of experimental L. monocytogenes meningitis of rabbits.


Apmis | 2003

Comamonas testosteroni meningitis in a patient with recurrent cholesteatoma

Bilgin Arda; Sohret Aydemir; Tansu Yamazhan; Abdullahi Hassan; Alper Tünger; Demir Serter

Comamonas testosteroni, a lesser‐known member of the genus, has shown little apparent capacity for causing infections in humans. We here present a case of purulent meningitis due to C. testosteroni, which occurred in a patient who had recurrent cholesteatoma. Ceftriaxone treatment was not effective in this patient even though in vitro the bacteria were susceptible to the drug. The patient responded well to meropenem therapy.


Journal of Clinical Microbiology | 2010

Meningitis Due to Providencia stuartii

Oguz Resat Sipahi; Selin Bardak-Ozcem; Erkin Ozgiray; Sohret Aydemir; Taskin Yurtseven; Tansu Yamazhan; Meltem Tasbakan; Sercan Ulusoy

ABSTRACT In this report, we present a case of postneurosurgical meningitis due to Providencia stuartii, which was treated successfully with meropenem therapy lasting 21 days.


Medical Principles and Practice | 2005

In vitro activities of various antimicrobials against Brucella melitensis strains in the Aegean region in Turkey.

Tansu Yamazhan; Şöhret Aydemir; Alper Tünger; Demir Serter; Deniz Gökengin

Objective: To study in vitro activities of three quinolones (ciprofloxacin, levofloxacin, moxifloxacin), four macrolides (erythromycin, dirithromycin, azithromycin, clarithromycin) and doxycycline against 44 clinical isolates of Brucella melitensis. Materials and Methods: Forty-four B. melitensis strains were isolated from blood cultures of adult patients with acute brucellosis who were hospitalized in the clinical ward of the Department of Clinical Microbiology and Infectious Diseases. The minimum inhibitory concentrations (MICs) of the tested antimicrobials were measured by the agar dilution method. MIC90 and MIC50 values were defined as the lowest concentration of the antibiotic at which 90 and 50% of the isolates were inhibited, respectively. Results: Doxycycline (MIC50: 0.25 µg/ml, MIC90: 0.50 µg/ml) had the lowest MIC in vitro against the B. melitensis strains. Among the quinolones, ciprofloxacin and levofloxacin had similar activities (MIC50: 0.5 µg/ml, MIC90: 2 µg/ml), whereas MIC of moxifloxacin (MIC50: 1 µg/ml, MIC90: 8 µg/ml) was higher than both antibiotics in this group. Clarithromycin and azithromycin were the most active macrolides (MIC50: 8 µg/ml and MIC90: 32 µg/ml), followed by erythromycin (MIC50: 16 µg/ml, MIC90: 32 µg/ml) and dirithromycin (MIC50: 64 µg/ml and MIC90: 64 µg/ml). Conclusion: The results indicate that the conventional agent doxycycline is more active than quinolones and macrolides against the B. melitensis in vitro.


Journal of Chemotherapy | 2005

Comparison of sequence analysis and INNO-LiPA HBV DR line probe assay in patients with chronic hepatitis B.

Ruchan Yazan Sertoz; S. Erensoy; S. Pas; U.S. Akarca; F. Ozgenc; Tansu Yamazhan; T. Ozacar; H.G.M. Niesters

Abstract The aim of this study was to compare direct sequence analysis of partial HBV pol gene and Inno-LiPA HBV DR in serum samples of 120 chronic hepatitis B patients sent to the Clinical Microbiology Laboratory of Ege University Hospital because of lamivudine resistance. Sequence analysis was performed on ABI Prism 310 Genetic Analyzer. Comparison of Inno-LiPA and sequence results obtained by double-blind evaluation showed full agreement (both at rt180 and rt204) in 58.8% of samples. Visually rechecking of the electropherograms increased this rate to 68.3%. Codon based rates are 81.7% and 75.8% at rt180 and rt204 respectively. LiPA detected variants in additional 12 (10%) samples, but missed one variant sample (both rt180 and rt204) and one sample was indeterminate due to poor probe binding. LiPA allows determination of mixed variants and seems to be more sensitive and simple for routine testing even though sequence analysis is still the gold standard for detecting new variants.


European Journal of Gastroenterology & Hepatology | 2011

Correlation between intrahepatic hepatitis B virus cccDNA levels and other activity markers in patients with HBeAg-negative chronic hepatitis B infection.

Rahmet Guner; Mustafa Kasım Karahocagil; Mehmet Buyukberber; Özlem Kandemir; Onur Ural; Gaye Usluer; Dilara Inan; Iftihar Koksal; Nurcan Baykam; Kenan Hizel; Tansu Yamazhan; Saban Esen; Mehmet A. Tasyaran

Objective The aim of this study was to demonstrate the relation between intrahepatic (IH) hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) levels and the other HBV replicative intermediates and hepatocyte expression of HBV antigens. Patients and methods Patients with hepatitis B surface antigen (HBsAg) positivity, hepatitis B early antigen negativity, serum HBV DNA levels 104 copies/ml or more, and constantly or intermittently increased alanine aminotransferase levels were included. Results Fifty-nine patients were included. There was a good correlation between the levels of IH HBV cccDNA and serum HBV DNA (P<0.001). Serum HBsAg levels were weakly correlated with IH HBV cccDNA levels and moderately correlated with serum HBV DNA (r=0.322, P=0.017; r=0.489, P=0.001, respectively). There were no significant correlation between serum HBsAg level and histologic activity index groups (P=0.691), but stage 0, 1, and greater than 2 fibrosis groups were positively correlated with serum HBsAg levels (P=0.019). IH cccDNA and serum HBV DNA were significantly different in hepatitis B core antigen staining groups (P=0.008 and <0.001, respectively) but there was no significant correlation between HBsAg staining groups and HBV replication markers. There was a weak correlation between serum HBsAg levels and IH HBsAg and hepatitis B core antigen levels (r=0.333, P=0.012; r=0.366, P=0.006, respectively). In multivariate analysis, alanine aminotransferase, age, fibrosis stage, and serum HBsAg quantitation were the most important factors predicting IH HBV cccDNA level. Conclusion Histopathologic damage, serum HBV DNA levels, and IH HBV replication markers have a more complex and dynamic process. However, both serum and IH HBV replication markers provide important knowledge about the activity of the disease.


Journal of Clinical Microbiology | 2010

Meningitis due to Providencia stuartii: a case report

Oguz Resat Sipahi; Selin Bardak-Ozcem; Erkin Ozgiray; Sohret Aydemir; Taskin Yurtseven; Tansu Yamazhan; Meltem Tasbakan; Sercan Ulusoy

ABSTRACT In this report, we present a case of postneurosurgical meningitis due to Providencia stuartii, which was treated successfully with meropenem therapy lasting 21 days.

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