The contribution of PET/CT to the differentiation of benign and malignant pleural effusion in patients with ovarian carcinoma.

OBJECTIVE: The present study investigates the ability of non-invasive contribution of positron emission tomography (PET)/computed tomography (CT) to distinguish between benign pleural effusions (BPE) and malignant pleural effusions (MPE) in patients diagnosed with ovarian carcinoma (OC). MATERIAL AND METHODS: Included in the study were 32 OC patients with a PE diagnosis. The cases with BPE and MPE were compared in terms of the PE maximum standardized uptake value (SUVmax), PE SUVmax/mean standardized uptake (SUVmean) value of the mediastinal blood pool (TBRp), the presence of pleural thickening, the presence of supradiaphragmatic lymph node, unilateral or bilateral PE, pleural effusion diameter, patient age and CA125 value. RESULTS: The mean age of the 32 patients was 57±2.8 years. TBRp>1.1, pleural thickening and supradiaphragmatic lymph node were observed significantly more frequently in the MPE than the BPE cases. While no pleural nodules were detected in patients with BPE, they were present in 7 of the patients with MPE. The rates of distinction between the MPE and BPE cases were as follows: the sensitivity of the TBRp value was 95.2% and specificity was 72.7%; the sensitivity of pleural thickness was 80.9% and specificity was 81.8%; the sensitivity of supradiaphragmatic lymph node was 38% and specificity was 90.9%; and the sensitivity of the pleural nodule was 33.3% and specificity was 100%. There were no significant differences between two groups in any other factors. CONCLUSIONS: Pleural thickening and TBRp values ascertained through PET/CT may aid the distinction between MPE-BPE, especially in patients with advanced stage OC with a poor general condition, or those who cannot undergo surgery.

Volumetric PET parameters are predictive for the prognosis of locally advanced cervical cancer.

BACKGROUND: The present study evaluates the relationship between PET/CT findings and survival in patients with locally advanced cervical cancer (LACC) with a squamous cell histology. METHODS: The study included 70 patients with LACC (FIGO stage IB2-IVA). The relationship between pretreatment PET/CT parameters, age, stage, lymph node metastasis and survival was evaluated using the univariate and multivariate Cox proportional hazards model. RESULTS: The mean age of the 70 patients was 57.4 years and the mean duration of follow-up was 33.6 months. Disease progression occurred in 36 patients and 32 patients died during the follow-up period. In the univariate analysis, MTV-P and TLG-P were found to be related to progression-free survival (PFS), and stage, MTV-P, TLG-P and SUVmax-Ps were found to be related to overall survival (OS). However, only MTV-P and TLG-P were found to be independent prognostic factors for both PFS and OS. CONCLUSIONS: The present findings suggest that volumetric PET parameters (MTV-P, TLG-P) predict the progression and survival of the patients with LACC.

FDG PET/CT signs of proven pulmonary hydatid cyst: is there any clue?

PURPOSE: Pulmonary hydatid cyst (PHC) can imitate many diseases. Sometimes, positron emission tomography/computed tomography (PET/CT) is performed in terms of malignancy exclusion for complicated cysts. Although some specific findings (doughnut sign) have been identified in hydatid cyst of the liver, there is no specific sign described for PHC. The aim of this study is to investigate the presence of a common finding in PHC patients scanned with PET/CT inadvertently. MATERIALS AND METHODS: From January 2015 to 2020, patients proven to have PHC were analyzed retrospectively. From all the patients, only 17, having a previous PET/CT, were included the study. Lesions were evaluated in three groups according to FDG uptake: A, negative; B, focal; C, doughnut sign. RESULTS: The total number of patients was 17. Nine of the patients were male and the median age was 41.94 + 14.68 (16-65) years. SUV max of the lesions ranged from 0.5 to 15.8 (mean ± SE: 4.68). According to the FDG uptake of the lesions, five were in Group A, two in Group B, and the remaining ten (58.8%) in Group C with doughnut sign. To correlate the CT findings with PET/CT findings, doughnut sign, which is a typical finding of hydatid cysts of liver, is seen in only four patients in Group 1-classified cysts which are non-complicated. But in Group 2 (n = 3) and 3(n = 4), the finding of doughnut sign is three in both groups. CONCLUSIONS: PET/CT is not a recommended imaging technique for PHC, but in cases where a definitive diagnosis is difficult, interpreting PET/CT findings is significant. This study demonstrates that previously described doughnut sign for liver hydatid cysts is also common for perforated pulmonary cysts. According to our knowledge, this is the first largest series of determining PET/CT findings of PHC. Further larger series will contribute to the literature.

Clinical value of metabolic PET parameters of primary vulvar carcinoma.

PURPOSE: We aim to establish the prognostic value of metabolic parameters of the primary tumor in patients diagnosed with vulvar squamous cell carcinoma (VSCC) who underwent a pretreatment F-18 FDG PET/CT scan. MATERIALS AND METHODS: This retrospective study included 47 patients with a histopathologically confirmed diagnosis of VSCC, and who underwent a F-18 FDG PET/CT scan prior to treatment. The disease stage and age at diagnosis, and the maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) values of the primary tumor, based on a baseline PET scan, were recorded. The relationship between these factors, and progression-free survival (PFS) and overall survival (OS) was evaluated. RESULTS: The mean age of the 47 study patients was 69.6±1.9 years. Among the patients, 18 were in early stage of the disease and 29 were in the advanced stage. The age, and SUVmax, SUVmean, MTV and TLG values were statistically significantly associated with OS and PFS. Furthermore, it was noted that OS and PFS were significantly longer in the early stage patients than in the advanced stage patients, in patients with a tumor size <4cm than those with a tumor size ≥4cm, and in patients with a negative lymph node metastasis than those with a positive lymph node metastasis. CONCLUSION: Our findings suggest that PET parameters are prognostic factors for VSCC. To the best of our knowledge, this study is the first to investigate the prognostic value of the PET parameters of primary tumors in patients with VSCC, and as such, we believe it contributes to literature.

Why is it important to report early possible COVID-19 PET/CT findings in cancer patients? Explaining with a case series.

BACKGROUND: Coronavirus disease-2019 (COVID-19) causing a pandemic mostly results in mild symptoms; however, it can evolve into serious complications. It is emphasized that if the term from the recent anticancer treatment to the diagnosis of COVID-19 was short, the probability of serious events increased in cancer patients. Therefore, early detection of COVID-19 and prevention of serious events is very important. We aimed to investigate whether it is possible to detect COVID-19 early by positron emission tomography (PET)/computed tomography (CT). METHODS: We retrospectively evaluated the images and clinical findings of patients who underwent PET/CT due to malignancy and whose COVID-19 polymerase chain reaction (PCR) test were detected positive subsequently. RESULTS: Eight cancer patients with positive COVID-19 PCR tests were included in the study. PET/CT revealed subpleural ground-glass opacities (GGOs) showing mild fluorodeoxyglucose (FDG) uptake that could be compatible with COVID-19 in 4 of 8 patients. The number of affected lobes ranged from 1-4. All patients were diagnosed with COVID-19 by PCR test when symptoms and/or lung findings worsened on the days after PET/CT. The time interval between the last anticancer treatment and COVID-19 diagnosis in five patients was ≤7 days. During the follow-up, six of the cases (75%) needed mechanical ventilation and died later. CONCLUSION: COVID-19 may be recognised early by detecting incidental findings in PET/CT, especially in asymptomatic cancer patients. Potential complications may be prevented by early diagnosis and anticancer therapy changes. Therefore, possible COVID-19 findings in PET/CT should be reported and the patient should be referred to relevant clinician.

PET/CT Parameters are Useful in Discrimination of Incidental Benign, Premalignant and Malignant Colonic Lesions.

AIM: The present study evaluates the role of PET parameters pertaining to incidentally detected foci of colorectal uptake (IFCU) on FDG PET/CT in the differentiation of benign, premalignant and malignant lesions. METHODS: This retrospective study included 74 patients. The colonoscopic and histopathological findings were regarded as the reference standards. The results were evaluated on a lesion basis by dividing the lesions into three groups as benign, premalignant and malignant. The maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume(MTV) and total lesion glycolysis(TLG) values of the three groups were compared. RESULTS: There were 88 IFCU in a total of 74 patients (27 female, 47 male, mean age 65 years). Of the 88 IFCU, 26 were qualified as benign, 42 as premalignant and 20 as malignant. Malignant + premalignant lesions were found in 62/88 (70.4 %) of the IFCU. The SUVmax of the benign lesions was significantly lower than those of the premalignant and malignant lesions; and SUVmean was lower than that of the malignant lesions. The MTV of the malignant lesions was significantly higher than that of the premalignant and benign lesions; and TLG was higher than that of the premalignant lesions. The optimum cut-off value in differentiating between the malignant and non-malignant lesions was 9.15 for SUVmax, 5.05 for SUVmean, 4.7 for MTV and 30.25 for TLG. CONCLUSION: PET parameters can guide the differentiation of benign, premalignant and malignant lesions with IFCU. Besides, patients with IFCU should undergo further evaluation due to high probability of premalignant and malignant lesions.

The value of PET/CT in determining lymph node metastasis of endometrial cancer.

OBJECTIVES: In our study, the role of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) in determining lymph node metastasis of endometrial cancer was evaluated. MATERIAL AND METHODS: The present retrospectively registered study included 80 patients with endometrial cancer who underwent PET/CT in preoperative period. The patients underwent total hysterectomy with bilateral salpingo-oophorectomy and lymph node dissection. Lymph node status was evaluated in histopathologic examination and PET/CT imaging and, the results were compared. RESULTS: There were 80 patients (mean age 62 years) in the present study. Lymph node metastasis was detected in five patients, whereas 75 patients had no lymph node metastasis. A total of 1,471 lymph nodes were examined histopathologically, revealing benign findings in 1,433 (pelvic = 1018, paraaortic = 415) and malignant findings in 38 (pelvic = 28, paraaortic = 10) lymph nodes. The accuracy, sensitivity and specificity of PET/CT in determining lymph node metastasis was 95%, 80% and 96% in patient-based evaluation, and 97.4%, 78.9% and 98.6% in lymph node-based evaluation, respectively. The detection sensitivity of PET/CT was 0%, 81.4% and 100% in metastatic lymph nodes with a short diameter of ≤ 4 mm, 5-9 mm and ≥ 10 mm, respectively. PET/CT could detect 73.3% of metastatic lymph nodes that had < 10 mm short diameter. CONCLUSIONS: PET/CT is useful method in detecting lymph node metastasis especially that are disregarded by CT or MR in endometrial cancer. Although PET/CT doesn't fully replace the surgical staging, its utilization in preoperative period may guide surgical procedure.

Prognostic role of PET/CT in endometrial cancer.

OBJECTIVES: The present study evaluates the prognostic value of metabolic parameters related to the primary tumor identifiedin preoperative fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) scans inpatients with endometrial cancer (EC). MATERIAL AND METHODS: This study included 120 patients with EC who underwent PET/CT in the preoperative period. Thepatients' age, maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume (MTV) and the totallesion glycolysis (TLG) value of the primary tumor on PET/CT; as well as the stage, histological subtype, grade and size ofthe primary EC; the degree of myometrial invasion (MI) cervical invasion (CI), lymphovascular invasion (LVI), lymph nodemetastasis (LNM) and distant metastasis (DM) were all recorded. The relationship of these factors with progression-freesurvival (PFS) and overall survival (OS) was evaluated. RESULTS: The study included 120 patients with EC with a mean age of 62.3 ± 0.02 years. Of the total, 32 patients diedaround the time of the analysis and 38 patients showed disease progression. The mean OS was 32.7 ± 1.6 months and themean PFS was 30.5 ± 2.8 months. No significant relationship was identified between the SUVmax, SUVmean, MTV, TLGvalues, patient age, tumor size, histology, grade and MI degree, and OS or PFS. Disease stage, LVI, CI, LNM and DM wereidentified as prognostic factors for OS and PFS. CONCLUSIONS: The present study found no significant relationship between preoperative PET parameters in EC and OS andPFS, although prospective studies involving a larger number of patients are required.

The role of positron emission tomography/computed tomography in the evaluation of anterior mediastinal masses and differentiating between the histological subtypes of thymic epithelial neoplasms.

BACKGROUND: This study aims to investigate the role of positron emission tomography/computed tomography in differentiating between benign and malignant anterior mediastinal masses and between the histological subtypes of thymic epithelial neoplasms. METHODS: This retrospective study included a total of 57 patients (30 males, 27 females; mean age 48.9 years; range, 14 to 78 years) who underwent an fluorodeoxyglucose positron emission tomography/ computed tomography with an indication of an anterior mediastinal mass between May 2010 and November 2018. The maximum and mean standardized uptake values, metabolic tumor volume, total lesion glycolysis, and mean Hounsfield units of the lesions were determined. Thymic epithelial neoplasms were classified as low-risk thymomas (A, AB, B1), high-risk thymomas (B2, B3), and thymic carcinomas. All lesions were evaluated together and divided into two groups as benign and malignant, and positron emission tomography/computed tomography parameters of the two groups were compared. RESULTS: Histopathological examination identified 29 thymic epithelial neoplasms (13 low-risk, 14 high-risk, two thymic carcinomas), 13 benign lesions, and 15 malignant lesions. No significant correlation was identified between the positron emission tomography/computed tomography parameters and histological subtype of thymic epithelial neoplasms. There was no significant difference in the maximum and mean standardized uptake values, metabolic tumor volume, total lesion glycolysis, and mean Hounsfield units of the lesions between low-risk and high-risk thymic carcinomas. The maximum and mean standardized uptake values, metabolic tumor volume, and mean Hounsfield units of the lesions were significantly higher in the malignant group than in the benign group. CONCLUSION: Our study results show that positron emission tomography/ computed tomography is useful in the differentiation of benign and malignant anterior mediastinal masses, although it fails to differentiate between the histological subtypes of thymic epithelial neoplasms.

The prognostic significance of serum CA125 levels with ER, PR, P53 and Ki-67 expression in endometrial carcinomas.

OBJECTIVES: The present study evaluates the relationship between the expression levels of hormone receptors (HRs), Ki-67, p53 and serum cancer antigen 125 (CA125) levels in endometrial cancer and clinicopathological risk factors, and determines their prognostic values. MATERIAL AND METHODS: This retrospective study included 49 patients with endometrial cancer whose estrogen receptor (ER) and progesterone receptor (PR) Ki-67 and p53 expression levels were determined through immunohistochemical methods, and whose preoperative serum CA125 levels were measured. These factors relationship with various clinicopathological factors, progression-free survival (PFS) and overall survival (OS) was investigated. RESULTS: The study included 49 patients with EC with a mean age of 61 ± 10 years. The rate of HR positivity was significantly higher in the endometrioid histology group than in the non-endometroid histology group (p = 0.026). A high level of Ki- 67 expression was found to be associated with a non-endometroid histology (p = 0.016), and a high tumor grade (p < 0.001) and a high p53 expression were found to be associated with advanced disease stage (p = 0.026). A positive correlation was found between p53 and Ki-67, a negative correlation was found between p53 and Ki-67 and the presence of HR. Significant relationship was not found between HR status, p53, Ki-67, CA125 and either other clinicopathological risk factors or survival. CONCLUSIONS: While HR positivity indicates favorable clinicopathological prognostic factors, high Ki-67 and high p53 expression indicate unfavorable ones. However, no direct effect of these factors on prognosis was found in this study.

Splenosis of the Liver Capsule.

Splenosis, a form of ectopic splenic tissue, is generally caused by heterotopic autotransplantation of splenic tissues after traumatic splenic rupture or splenectomy. The implants are often localized intraperitoneally, mostly in the left upper quadrant and splenic region. Hepatic foci are seen only on rare occasions. The differential diagnosis of splenosis foci from malignant masses can be challenging by conventional imaging and lead to unnecessary invasive procedures. This manuscript presents radiological and scintigraphic images of splenosis foci located in the peritoneal cavity and liver capsule of a 46-year-old man who underwent splenectomy due to traumatic splenic rupture 30 years ago.

The Contribution of Fluorine 18F-FDG PET/CT to Lung Cancer Diagnosis, Staging and Treatment Planning.

OBJECTIVE: Lung cancer is the most common cause of cancer-related death throughout the world, and the correct choice of treatment based on early diagnosis and staging increases the chance of survival. The present study aims to investigate the contribution of fluorine 18-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG PET/CT) to the management of lung cancer. METHODS: In this study, 50 patients who underwent 18F-FDG PET/CT for lung cancer diagnosis and staging between February 2012 and February 2014 were included. The maximum standardized uptake value (SUVmax) of the primary lung lesion along with other findings of 18F-FDG PET/CT and the results of histopathologic and conventional examinations were evaluated retrospectively. The mean survival time of patients was determined, and the findings were compared by using statistical methods. RESULTS: Histopathologic examinations revealed 51 lung cancers in 50 patients. The sensitivity, accuracy and positive predictive value of 18F-FDG PET/CT in detecting primary malignancy were 94%, 94%, 100%, respectively. Adenocarcinoma (n=23, 16.8±13.5) and squamous cell carcinoma (n=15, 17.9±5.6) did not differ significantly regarding their mean SUVmax values (p=0.2). A statistically significant positive correlation (r=0.4) was identified between tumor size and SUVmax value for 51 tumors (p=0.002). The 18F-FDG PET/CT result was true negative in nine, false positive in six, true positive in two, and false negative in four patients who underwent histopathologic evaluation of their lymph nodes. The 18F-FDG PET/CT changed treatment planning in 34% of the patients. No significant relationship was identified between SUVmax value of the tumor and patient survival in patients (p=0.118). CONCLUSION: The present study concluded that PET/CT was an efficient method in the diagnosis and staging of lung cancer since it provided useful information in addition to conventional methods. It was also observed that PET/CT scanning resulted in a change in therapeutic plans in the majority of patients. However, there was no statistically significant relationship between survival and the SUVmax of the primary mass.

Gram (-) microorganisms DNA polymerase inhibition, antibacterial and chemical properties of fruit and leaf extracts of Sorbus acuparia and Sorbus caucasica var. yaltirikii.

Investigation of novel plant-based agents might provide alternative antibiotics and thus fight antibiotic resistance. Here, we measured the ability of fruit and leaf extracts of Sorbus aucuparia (Sauc) and endemic Sorbus caucasica var. yaltirikii (Scau) to inhibit nonreplicative (Klenow Fragment-KF and Bacillus Large Fragment-BLF) and replicative (DnaE and PolC) bacterial DNA polymerases along with their antimicrobial, DPPH free radical scavenging activity (RSA), and chemical contents by total phenolic content and HPLC-DAD analysis. We found that leaf extracts had nearly 10-fold higher RSA and 5-fold greater TPC than the corresponding fruit extracts. All extracts had large amounts of chlorogenic acid (CGA) and rutin, while fruit extracts had large amounts of quercetin. Hydrolysis of fruit extracts revealed mainly caffeic acid from CGA (caffeoylquinic acid) and quercetin from rutin (quercetin-3-O-rutinoside), as well as CGA and derivatives of CGA and p-coumaric acid. Plant extracts of Sorbus species showed antimicrobial activity against Gram-negative microorganisms. Scau leaf extracts exhibited strong inhibition of KF activity. Sauc and Scau leaf extracts also strongly inhibited two replicative DNA polymerases. Thus, these species can be considered a potential source of novel antimicrobial agents specific for Gram-negative bacteria.

[Characterization of class 1 and class 2 integron gene cassettes in Escherichia coli strains isolated from urine cultures: a multicenter study]. / Idrar kültürlerinden izole edilen Escherichia coli suslarinda sinif 1 ve sinif 2 integron gen kasetlerinin karakterizasyonu: Çok merkezli bir çalisma.

Escherichia coli is the most common pathogen isolated from both nosocomial and community acquired urinary tract infections. Although there are many studies from different centers concerning the antibiotic susceptibility of E.coli isolates in Turkey, the studies are quite few about class 1 and class 2 integron cassettes in clinical E.coli isolates from urinary samples. The aim of the study was to investigate the antibiotic susceptibility and the carriage of integron gene cassettes in E.coli strains isolated from urinary samples. A total of 626 E.coli strains isolated from urine cultures in microbiology laboratories located at 10 provinces from different regions of Turkey (Denizli, Ankara, Kayseri, Nigde, Sanliurfa, Kahramanmaras, Tokat, Malatya, Konya and Trabzon) between June 2011-June 2012 were included in the study. The identification and antibiotic susceptibility testing of the isolates were studied by conventional methods as well as Vitek® 2 Compact (bioMérieux, France) and BD Phoenix™ 100 (Becton Dickinson, USA) systems. The antibiotic susceptibilities of all the isolates were retested by Kirby-Bauer disk diffusion method according to CLSI recommendations in the main center of the study in order to achive the standardization. The presence of integrons was detected with polymerase chain reaction (PCR) method by using specific primers targeting class 1 (intI1) and class 2 (intI2) integrase gene regions. After integron amplification the samples were cloned and subjected to DNA sequencing. When the antibiotic susceptibility of the isolates were evaluated, the highest resistance was observed against most commonly used empirical antibiotics namely ampicillin and trimethoprim-sulfamethoxazole (SXT) with the mean rate of 58.6% (range: 43.8%-73.2%) and 41.2% (range: 35.4%-45.8%), respectively. The most effective antibiotics detected against the isolates were imipenem and amikacin with the lowest resistance rates of 0.2% (range: 0%-1.1%) and 0.6% (range: 0%-3.2%), respectively. The frequency of positive IntI1 gene and class 1 integron gene cassettes were found as 25.8% (162/626) and 16.6% (104/626), respectively, whereas the frequency of positive intI2 gene II and class 2 integron gene cassettes were 5.1% (32/626) and 3% (19/626), respectively. The lowest intI1 gene frequency was detected in the isolates from Kayseri (16.6%) and the highest in the isolates from Kahramanmaras (35.4%) provinces. While there was no intI2 gene in the isolates from Denizli and Kayseri, the highest frequency was 12.1% in the isolates from Sanliurfa province. dfrA1 gene, the most frequent gene among integron gene cassettes was positive in 31 class 1 integron gene cassette alone, and positive with aadA1 gene in 18 class 1 integron gene cassettes. dfrA1 gene was positive with aadA1a just in one isolate. dfrA17 allele was positive in one isolate alone, in 28 isolates with aadA1, and in 15 isolates with aadA5. aadA1 gene was detected in four isolates. dfrA17-sat-aadA5 co-existence was detected among class 2 integron gene cassette in isolates from six provinces. dfrA1-sat-aadA1 was detected in one isolate from Ankara province and dfrA1 was detected in one isolate in Nigde province only. As a result, dfrA1 and aadA1 genes are the most common types of genes among class 1 and class 2 integron gene cassettes in E.coli isolated from urine cultures. It was concluded that high resistance against streptomycin (31.2%) and SXT (41.2%) supported the dissemination of integron-mediated genes dfr, sul1 and aad in the isolates.

[Investigation of the frequency and distribution of beta-lactamase genes in the clinical isolates of Acinetobacter baumannii collected from different regions of Turkey: a multicenter study]. / Türkiye'nin farkli bölgelerinden toplanan klinik Acinetobacter baumannii izolatlarinda beta-laktamaz gen sikligi ve dagiliminin arastirilmasi: Çok merkezli bir çalisma.

The diversity and distribution of TEM, SHV and CTX-M type of extended-spectrum beta-lactamases (ESBLs) are important for the treatment and control of infections. Determination of ESBL genes in clinical isolates by polymerase chain reaction (PCR) and DNA sequencing can obtain useful data for their molecular epidemiology and risk. The aim of this study was to investigate the frequency of beta-lactamase genes in Acinetobacter baumannii strains isolated from different regions of Turkey. A total of 519 A.baumannii strains collected from hospitals located at 12 different provinces of Turkey (Bolu (n= 67), Tokat (n= 47), Trabzon (n= 25), Ordu (n= 27), Diyarbakir (n= 47), Nigde (n=31), Kayseri (n= 36), Ankara (n= 41), Kirikkale (n= 26), Kahramanmaras (n= 25), Mersin (n= 40), Istanbul (n= 107)] between 2011-2012 period were included in the study. Identification of the isolates were performed by both conventional methods and automated systems, VITEK2 Compact (BioMerieux, France) and API 32GN (BioMerieux, France). Disc diffusion method was used for the detection of antibiotic susceptibilities of the isolates and the results were evaluated according to CLSI (Clinical and Laboratory Standards Institute) criteria. Tigecycline and colistin sensitivities of the isolates were evaluated according to BSAC (British Society for Antimicrobial Chemotherapy) criteria. The presence of beta-lactamase genes, namely blaoxa-51, blaTEM, blaSHV, blaCTX-M1, blaCTX-M2, blaGES and blaVIM were detected by PCR. In our study, the resistance rates against colistin, tigecycline, ampicillin-sulbactam, amoxicillin-clavulanic acid, cefoperazone/sulbactam, tobramycin, ceftriaxone, piperacillin-tazobactam, gentamicin, ampicillin, tetracycline, cefepime, piperacillin, amikacin, trimethoprim-sulfamethoxazole, meropenem, levofloxacin, ciprofloxacin, imipenem and ceftazidime were detected as; 0.6%, 2.7%, 11.9%, 15.2%, 21%, 22.9%, 23.9%, 48.6%, 59.5%, 61.8%, 66.3%, 67.8%, 69.2%, 71.1%, 77.5%, 78.6%, 81.1%, 82.9%, 87.5% and 89.4%, respectively. All of the isolates (100%) were OXA-51 positive, while 443 (85.4%) out of 519 strains harbored other beta-lactamase genes searched in the study. When the distribution of the genes were evaluated, blaTEM-1 was found as the predominant one with a frequency rate of 55.7% (n=289/519), followed by blaCTX-M2 (63/519, 12.1%), blaCTX-M1 (42/519, 8.1%), blaSHV (40/519, 7.7%), blaGES (8/519, 1.5%) and blaVIM (1/519, 0.2%). Cooccurence of ESBL genes was detected in 16.3% (72/443) of the strains, being mostly TEM+CTX-M2 (20/72, 27.8%), TEM+SHV (11/72, 15.3%) and TEM+CTX-M1 (10/72, 13.9%). In addition, it was noted that the distribution of ESBL genes between isolates showed differences according to the provinces. Accordingly, none of the strains isolated from four provinces (Bolu, Nigde, Mersin, Kahramanmaras) and from three provinces (Bolu, Kahramanmaras, Diyarbakir) harbored blaCTX-M1/M2 and blaSHV genes, respectively. The blaTEM gene was detected in isolates collected from all of the provinces, with a highest frequency in Nigde (28/31, 90.3%) and lowest in Trabzon (1/25, 4%). The presence of GES-11 type ESBLs was found only in the isolates sent from Nigde province (8/31; 25.8%). Screening of metallo-beta-lactamase VIM gene also yielded a single positive result amongst only Nigde isolates (1/31; 3.2%), and this gene was identified as VIM-5 type by DNA sequencing. This study which is the first comprehensive national research to characterize ESBLs in A.baumannii isolates by molecular methods, showed that the most prevalent ESBL type is TEM (289/519, 55.7%) amongst A.baumannii strains isolated from different regions of our country. The data of our study is parallel to the results of previous studies carried out from Turkey.

[Carriage of class 1 and 2 integrons in Acinetobacter baumannii and Pseudomonas aeruginosa isolated from clinical specimens and a novel gene cassette array: blaOXA-11-cmlA7]. / Klinik örneklerden izole edilen Acinetobacter baumannii ve Pseudomonas aeruginosa suslarinin sinif 1 ve 2 integron tasiyiciligi ve yeni bir gen kaseti birlikteligi: blaOXA-11-cmlA7.

The dissemination of antibiotic resistance genes between bacteria leads to serious problems in the treatment of infectious diseases. It has been shown that resistance genes can also be carried by the integrons. There are limited studies regarding the carriage of class 1 and 2 integrons in Acinetobacter baumannii and Pseudomonas aeruginosa clinical strains in Turkey. The aims of this study were to investigate the carriage rates of class 1 and class 2 integrons in A.baumannii and P.aeruginosa strains isolated from clinical samples in Abant Izzet Baysal University Hospital, and to characterize the antibiotic resistance gene cassettes in these integrons by sequence analyses. A total of 137 strains (77 A.baumannii and 60 P.aeruginosa) isolated from various clinical specimens (56% were sputum, 19% wound, 11% urine, 11% blood, 3% catheter), between March 2010-December 2012, were included in the study. The identification and antibiotic susceptibility tests of the isolates were performed by Vitek 2 Compact (bioMérieux, France) and BD Phoenix 100 (Becton Dickinson, USA) systems. The presence of integrons were screened by PCR method using specific primer pairs targeting class 1 (intI1) and 2 (intI2) integrase regions. All the samples that revealed integron amplification were subjected to DNA sequence analysis, both in the forms of cloned products and PCR amplicons. In the study, the highest susceptibility rates were found against colistin (96%) and tigecycline (78%) in A.baumannii, and against piperacillin/tazobactam (97%) and piperacillin (93%) in P.aeruginosa isolates. The highest resistance rate was determined for piperacillin/tazobactam (95%) in A.baumannii strains. The presence of intI1 gene was detected in 33% (26/77) of A.baumannii and 10% (6/60) of P.aeruginosa isolates. When variable regions in intI1 positive strains were amplified by PCR, eight (8/77, 10%) A.baumannii and three (3/60, 5%) P.aeruginosa strains were found to harbor antibiotic resistance gene cassettes. IntI2 gene was not detected in any of the isolates. Resistance to piperacillin/tazobactam, ceftazidime, cefepime, ceftriaxone and ampicillin/sulbactam was detected as the common resistance pattern in all integron-positive A.baumannii strains, whereas resistance to ceftazidime, gentamicin and ciprofloxacin was the common pattern in all integron-positive P.aeruginosa strains. DNA sequence analysis of variable regions of integrons indicated that two separate gene cassette arrays (aacC1-aadA1 and aac(3)-1) were carried by A.baumannii strains, and two types of gene cassette arrays (blaOXA-30-aadA1 and blaOXA-11-cmlA7) were carried by P.aeruginosa strains. To our best knowledge, this is the first report of the gene sequence of blaOXA-11-cmlA7 defined in an integron gene cassette of P.aeruginosa.

Nationwide study of Escherichia coli producing extended-spectrum ß-lactamases TEM, SHV and CTX-M in Turkey.

Four hundred and forty extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli isolates were collected from 10 different hospitals in Turkey between 2011 and 2012. Clinical specimens consisted of urine (80.45%), blood (6.59%), cerebrospinal fluid (1.13%), pleural fluid (2.95%), wound (4.31%) and sputum (4.54%). ESBL-coding genes (CTX-M1, CTX-M2, TEM, SHV) were detected by PCR. According to the PCR and sequencing results, CTX-M1 was the most prevalent ß-lactamase 83.18% (366/440), followed by TEM 44.09% (194/440), CTX-M2 31.81% (140/440) and SHV 1.81% (8/440). Sequencing results showed that TEM and SHV types were TEM-1b and SHV-11, respectively. Rate of the strains harboring only CTX-M1, CTX-M2, TEM-1b and SHV-11 were 30.90%, 3.63%, 2.27% and 0.23%, respectively. Rate of the strains harboring the combinations of CTX-M1-CTX-M2, CTX-M1-CTX-M2-TEM-1b, CTX-M2-TEM-1b, CTX-M1-TEM-1b, CTX-M1-CTX-M2-TEM-1b-SHV-11, CTX-M1-TEM-1b-SHV-11, CTX-M1-SHV-11, CTX-M1-CTX-M2-SHV-11, CTX-M2-SHV-11, CTX-M2-TEM-1b-SHV-11, TEM-1b-SHV-11 were 12.95%, 11.59%, 2.95%, 26.13%, 0.45%, 0.68%, 0.22%, 0.22%, 0%, 0% and 0%, respectively. This is a nationwide study of ESBL-producing E. coli in Turkey. These results shows that CTX-M1 group is the most common type of class A ß-lactamases among ESBL-producing E. coli strains in Turkey.