Antibiotic Resistance Profiles of Escherichia coli and Salmonella spp. Isolated From Dairy Farms and Surroundings in a Rural Area of Western Anatolia, Turkey.

Background Antibiotic resistance is a significant public health issue worldwide. Antibiotic-resistant zoonotic bacteria such as Escherichia coli (E. coli), Campylobacter, Salmonella, Listeria, Coxiella, and Mycobacterium can be particularly isolated from biofertilizers. Epidemiological studies have shown that cases of foodborne infections and intoxications are significantly related to animal-derived foods. The presence of these species in aquatic environments indicates areas or organisms contaminated with animal or human feces. Especially, the presence of E. coli in aquatic environments has become a serious problem worldwide. Pathogenic strains of E. coli cause waterborne and foodborne diseases. Materials and methods This study included a total of 290 samples collected from five different dairy farms between April and September 2023 which comprised 20 samples of cow manure, 20 samples of milk, three samples of dairy workers' hand washing water, five samples of soil, five samples of water, and five samples of vegetables. The samples taken from the farms were homogenized with 0.1% peptone water at a ratio of 1/10. They were then cultured on xylose lysine deoxycholate (XLD), eosin methylene blue agar (EMB), and blood agar media, and gram-negative colonies were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and the VITEK2 automated system (BioMerieux Inc., Durham, NC). Amplification of the isolated DNA extracts was performed with A.B.T.™ 2X HS-PCR MasterMix (A.B.T Laboratory Industry, Arnavutköy, Turkey) in the SimpliAmp™ thermal cycler (Thermo Fischer Scientific Inc., Waltham, MA) and visualized by agarose gel electrophoresis. Results Among the 52 E. coli strains isolated in our study, the highest antibiotic sensitivity rate was observed in meropenem, while the lowest sensitivity rates were determined in cefazolin and cefuroxime. While two of the Salmonella spp. (n = 2) isolates were found to be resistant to tetracycline, and one was found to be resistant to penicillin and ampicillin. No resistance to trimethoprim/sulfamethoxazole was detected in either isolate. Extended-spectrum beta-lactamases (ESBLs) were detected in only four (7.7%) E. coli strains. While tetA, tetB, and TEM genes were seen in almost all E. coli strains, they were not found in Salmonella spp. Conclusion In conclusion, our study revealed the presence of antimicrobial resistance genes in E. coli and Salmonella spp. isolates collected from various farms and environmental samples, which render the antimicrobials used for disease treatment ineffective. Consequently, research should be undertaken to prevent the development of new resistance genes in our country, as creating new medications and treatment strategies for these diseases is costly and time-intensive.

Investigation of Plasmid-Mediated Colistin Resistance Genes (mcr-1-8) in Enterobacterales Isolates.

Background The escalating global rise in multidrug-resistant gram-negative bacteria presents an increasingly substantial threat to patient safety. Over the past decade, carbapenem-resistant Enterobacterales (CRE) have emerged as one of the most critical pathogens in hospital-acquired infections, notably within intensive care units. Colistin has become one of the last-resort antimicrobial agents utilized to combat infections caused by CRE. However, the use of colistin has been accompanied by a notable increase in the prevalence of colistin-resistant bacteria. This study aimed to investigate plasmid-mediated colistin resistance genes ranging from mcr-1 to mcr-8 among members of the Enterobacterales order. Materials and methods This prospective study was conducted in the microbiology laboratory of Afyonkarahisar Health Sciences University Health Research and Practice Center between May 1, 2021 and July 31, 2022. A total of 2,646 Enterobacterales isolates were obtained from all culture-positive clinical samples sent from various clinics. Of these, 79 isolates exhibiting resistance to carbapenem antibiotics were included in the study. Among the 79 isolates, the presence of mcr-1 to mcr-8 genes was investigated in 27 isolates that were shown to be resistant to colistin. The identification of bacteria at the species level and antibiotic susceptibility tests were conducted using the VITEK 2 automated system (bioMérieux, USA). Colistin resistance among Enterobacterales strains exhibiting carbapenem resistance was evaluated using the broth microdilution technique (ComASP™ Colistin, Liofilchem, Italy), in accordance with the manufacturer's instructions. Results In our in vitro investigations, the minimum inhibitory concentration (MIC) values for meropenem were determined to be >8 µg/ml, whereas for colistin, the MIC50 value was >16 µg/ml and the MIC90 value was 8 µg/ml. A total of 27 colistin-resistant strains were identified among the 79 carbapenem-resistant Enterobacterales strains analyzed. The most prevalent agent among colistin-resistant strains was Klebsiella pneumoniae (K. pneumoniae), representing 66.7% of the isolates. This was followed by Proteus mirabilis (P. mirabilis) with 29.6% and Escherichia coli (E. coli) with 3.7%. The colistin resistance rate among carbapenem-resistant strains was found to be 34.2%, with colistin MIC values in strains tested by the broth microdilution method ranging from 4 to >16 µg/ml concentrations. In polymerase chain reaction (PCR) studies, the mcr-1 gene region was successfully detected by real-time PCR in the positive control isolate. Nevertheless, none of the gene regions from mcr-1 to mcr-8 were identified in our study investigating the presence of plasmid-mediated genes using a multiplex PCR kit. Conclusion Although our study demonstrated the presence of increased colistin resistance rates in carbapenem-resistant Enterobacterales isolates, it resulted in the failure to detect genes from mcr-1 to mcr-8 by the multiplex PCR method. Therefore, it is concluded that the colistin resistance observed in Enterobacteriaceae isolates in our region is not due to the mcr genes screened, but to different resistance development mechanisms.

Pulse Methylprednisolone-Induced Sinus Bradycardia: A Case Report.

Corticosteroids have a wide range of uses. The most commonadverse side effectsofhigh-dosepulse steroids are hyperglycemia, gastrointestinal intolerance, and psychiatric symptoms. Cardiac arrhythmias have been reported in patients who receive high-dose steroid therapy. Bradycardia is a rare adverse side effect of pulse steroid therapy. We present the case of a 57-year-old male patient who developed symptomatic sinus bradycardia after he received pulse methylprednisolone therapy as treatment for graft-versushost disease. The patient's pulse steroid therapy was discontinued, and the dose of methylprednisolone was reduced to 100 mg/day. He was treated conservatively and with close observation; the patient's heart rate increased to 68 beats/min after 1 day, and then to 78 beats/min. The diagnosis of methylprednisolone-induced bradycardia was made after exclusion of other common etiologies of sinus bradycardia. This case report demonstrates the importance of careful cardiovascular monitoring in patients who receive high-dose methylprednisolone because of dose-related cardiovascular risks.

Use of n-acetylcysteine therapy in patients with relapsed refractory thrombotic thrombocytopenic purpura.

There is limited data on the use of NAC in the literature. We would like to present the satisfactory results we obtained in our resistant and relapsed patients as a case series.Thrombotic thrombocytopenic purpura (TTP) is a life-threatening thrombotic microangiopathy caused by ADAMTS13 (a disintegrin with thrombospondin type 1 motif and metalloprotease activity, member13) deficiency. Von Willebrand factor (vWF) initiates platelet aggregation and thus thrombus formation. The multimers of vWF are cleaved by ADAMTS13. Because of the decreased activity of ADAMTS13, ultra-large multimers accumulate and end-organ damage occurs. TTP is characterized by microangiopathic hemolytic anemia (MAHA), severe thrombocytopenia, and organ ischemia resulting from vascular occlusion caused by thrombi. Plasma exchange therapy (PEX) remains the mainstay of TTP therapy. Patients who do not respond to PEX and corticosteroids require additional treatments such as rituximab and caplacizumab. NAC reduces disulfide bonds in mucin polymers through its free sulfhydryl group. Thus, the size and viscosity of the mucins are reduced. VWF is structurally similar to mucin. Based on this similarity, Chen and colleagues showed that NAC can reduce the size and reactivity of ultralarge multimers of vWF, such as ADAMTS13. Currently, there is not much information to suggest that NAC has any clinical value in the treatment of TTP. In this case series of 4 refractory patients, we would like to present the responses we obtained with the addition of NAC therapy. NAC can be added to PEX and glucocorticoid therapy as supportive therapy, especially in unresponsive patients.

International Forum: The Turkish perspective on apheresis activity: The Turkish apheresis registry report.

Therapeutic apheresis is an extracorporeal treatment that selectively removes abnormal cells or harmful substances in the blood that are associated with or cause certain diseases. During the last decades the application of therapeutic apheresis has expanded to a broad spectrum of hematological and non-hematological diseases due to various studies on the clinical efficacy of this procedure. In this context there are more than 30 centers performing therapeutic apheresis and registered in the apheresis database in Turkey. Herein, we, The Turkish Apheresis Registry, aimed to analyze some key articles published so far from Turkey regarding the use of apheresis for various indications.

Use of Eculizumab in Thrombotic Microangiopathy Associated with Hematopoietic Stem Cell Transplantation.

Thrombotic microangiopathy (TMA) associated with hematopoietic stem cell transplantation, remains a difficult complication due to its high mortality rate, lack of standardised diagnostic criteria, and limited treatment options. Although the etiology of the disease is not clear, medications, radiotherapy, graft-versus-host disease (GVHD), angioinvasive fungal, viral infections and complement activation have been implicated. Agents such as therapeutic plasma exchange (TPE), steroids, rituximab, defibrotide, eculizumab are used in its treatment. The use of treatments such as TPE, steroids, defibrotide, and rituximab did not yield satisfactory results in transplant-associated TMA (TA-TMA). Recent studies have reported successful results with eculizumab in the treatment of TA-TMA. As there is no standard dose for eculizumab in the treatment of TA-TMA, doses used in atypical hemolytic uremic syndrome (aHUS) were administered. In this paper, we present a case that was unresponsive to TPE and steroids, but which was successfully treated with eculizumab. Key Words: Acute myeloid leukemia, Stem cell transplantation, Thrombotic microangiopathy, Apheresis, Eculizumab.

Clinical characteristics and therapeutic outcomes of paroxysmal nocturnal hemoglobinuria patients in Turkey: a multicenter experience.

The aim of this study is to collect paroxysmal nocturnal hemoglobinuria (PNH) patient data from hematology centers all over Turkey in order to identify clinical features and management of PNH patients. Patients with PNH were evaluated by a retrospective review of medical records from 19 different institutions around Turkey. Patient demographics, medical history, laboratory findings, and PNH-specific information, including symptoms at the diagnosis, complications, erythrocyte, and granulocyte clone size, treatment, and causes of death were recorded. Sixty patients (28 males, 32 females) were identified. The median age was 33 (range; 17-77) years. Forty-six patients were diagnosed as classic PNH and 14 as secondary PNH. Fatigue and abdominal pain were the most frequent presenting symptoms. After eculizumab became available in Turkey, most of the patients (n = 31/46, 67.4%) were switched to eculizumab. Three patients with classic PNH underwent stem cell transplantation. The median survival time was 42 (range; 7-183 months) months. This study is the first and most comprehensive review of PNH cases in Turkey. It provided us useful information to find out the differences between our patients and literature, which may help us understand the disease.

Presence of paroxysmal nocturnal hemoglobinuria in patients with idiopathic portal vein thrombosis: a single-center study

Background/aim: Paroxysmal nocturnal hemoglobinuria (PNH) is a very rare clonal hematopoietic stem cell disease characterized by chronic hemolytic anemia and thrombosis. We report data from a study of the occurrence of PNH among patients with idiopathic portal vein thrombosis (PVT). Materials and methods: Patients who were followed up with the diagnosis of idiopathic PVT were enrolled into this study. Those with laboratory and/or imaging evidence of any local or systemic factor that could lead to PVT were excluded. PNH clone was examined in all patients using established FLAER methodology. Results: A total of 112 patients (42 males and 70 females), none of them had a markedly PNH clone, but 4 patients (3.6%) with confirmed tests two times had small PNH clones (size between 3.02% and 4.62%). The median ages of PNH clone (-) and PNH clone (+) patients were 42 (range; 24­59) vs 39 (range; 36­42) years, respectively. The median hemoglobin concentration, platelet count and leukocyte count were lower in the PNH clone (+) group than the PNH clone (-) group. Anemia, thrombocytopenia, and leukopenia were detected in all PNH clone (+) patients. In addition, the PNH clone positivity size in monocytes was higher than erythrocytes in all of 4 patients. Conclusions: PNH should be considered during differential diagnosis among patients with idiopathic PVT. Small PNH clones can be detected in PVT patients that we cannot clearly determine its relationship with PVT. We need furthermore studies to explore the potential role of this finding.

Comparison of the effects of oral iron treatment every day and every other day in female patients with iron deficiency anaemia.

BACKGROUND: It is known that daily divided doses and high doses of iron increase hepcidin and reduce iron absorption. AIM: This study aimed to compare treatments of iron replacement every other day at low doses, once a day and twice a day in terms of their effectiveness and frequencies of side effects. METHODS: For a month, Group I received 270 mg ferrous sulphate twice a day (total elemental iron dose: 160 mg/day), Group II received 270 mg ferrous sulphate once a day (total elemental iron dose: 80 mg/day), and Group III received 270 mg ferrous sulphate every other day (total elemental iron dose: 80 mg/every other day). Intragroup and intergroup statistical analyses were carried out. RESULTS: Haemoglobin (Hb) increased significantly in all three groups (P = 0.00). The increase in Hb levels was similar among the groups (P = 0.09). Ferritin significantly increased in all three groups after the treatment (P = 0.00). The increase in ferritin in Group I was significantly higher than those in Groups II and III (P < 0.05). Gastrointestinal tract (GIS) side effects were also significantly higher in Group I in comparison to the others (P = 0.001). CONCLUSIONS: A low-dosage of iron treatment every other day may be used in the place of providing iron once or twice every day with similar effectiveness and lower rates of GIS side effects.

Decreased bone mineral density and associated factors in severe haemophilia A patients: A case-control study.

INTRODUCTION: Haemophilia patients may exhibit lower levels of bone mineral density (BMD) than the general population for a variety of reasons. AIM: We aimed to investigate decreased BMD in people with severe adult haemophilia A (PWH) living in eastern Turkey, and to evaluate the related potential risk factors. METHODS: The study included 41 PWH and 40 healthy volunteers. Dual-energy x-ray absorptiometry (DXA) was used to measure the BMD. Blood tests and body mass index (BMI) were recorded. The Functional Independence Score in Hemophilia (FISH) test was used to measure functional ability status. RESULTS: There was a significant difference between the PWH and control groups with respect to femoral neck and total hip BMD (in g/cm2 ), but the difference for lumbar spine was not significant (P = .017, P < .001, P = .071, respectively). In PWH, patients under 50 years of age, 19.4% were found to have "lower than expected" BMD levels for their age, while 27.8% showed "low normal" levels. In PWH, osteoporosis was found in 60% of the patients over 50 and osteopenia in 20%. Vitamin D insufficiency and deficiency were present in 63.4% of the PWH, significantly higher than the control group (37.5%; P < .001). CONCLUSION: The results indicated that the decrease in BMD was significantly greater in patients with severe haemophilia A than in the normal healthy population. This reduction was correlated with BMI, vitamin D and low functional ability status. However, in multivariate analysis, none of these was a strong independent risk factor.

The Turkish experience with therapeutic plasma exchange: A national survey.

Therapeutic plasma exchange (TPE) is used to treat more than 60 diseases worldwide and has drawn growing interest. Little is known about the current situation of TPE activity in Turkey, so we developed a survey to obtain information about this timely topic. We collected data on TPE from 28 apheresis units throughout Turkey. We performed a total of 24,912 TPE procedures with 3203 patients over the past decade. Twenty years ago, the majority of procedures were performed for neurological and hematological disorders, and today, most TPE procedures are done for the same reasons. The only historical change has been an increase in TPE procedures in renal conditions. Currently, renal conditions were more frequently an indication for TPE than rheumatic conditions. Fresh frozen plasma was the most frequently used replacement fluid, followed by 5% albumin, used in 57.9% and 34.6% of procedures, respectively. The most frequently used anticoagulants in TPE were ACD-A and heparin/ACD-A, used with 1671 (52.2%) and 1164 (36.4%) patients, respectively. The frequency of adverse events (AEs) was 12.6%. The most common AEs were hypocalcemia-related symptoms, hypotension, and urticaria. We encountered no severe AEs that led to severe morbidity and mortality. Overall, more than two thirds of the patients showed improvement in the underlying disease. Here, we report on a nationwide survey on TPE activity in Turkey. We conclude that there has been a great increase in apheresis science, and the number of TPE procedures conducted in Turkey has increased steadily over time. Finally, we would like to point out that our past experiences and published international guidelines were the most important tools in gaining expertise regarding TPE.

Relapsed/refractory thrombotic thrombocytopenic purpura treated with N-acetylcysteine: a case report.

Thrombotic thrombocytopenic purpura is a rare condition that presents with microangiopathic haemolytic anaemia, thrombocytopaenia, fever, renal impairment and neurological symptoms. Plasma exchange is a lifesaving treatment for this condition. However, some cases may be non-responsive to plasma exchange, or loss of response may occur. Treatment options for refractory cases include high-dose corticosteroids, rituximab, vincristine, cyclophosphamide, splenectomy, bortezomib and N-acetylcysteine. We present a refractory case of thrombotic thrombocytopenic purpura responding to the last of these therapies.

[Identification of anaerobic gram-negative bacilli isolated from various clinical specimens and determination of antibiotic resistance profiles with E-test methods]. / Çesitli klinik örneklerden izole edilen gram-negatif anaerop basillerin tiplendirilmesi ve antibiyotik direnç profillerinin E-test yöntemi ile belirlenmesi.

The aim of this study was to identify gram-negative anaerobic bacilli isolated from various clinical specimens that were obtained from patients with suspected anaerobic infections and to determine the antibiotic resistance profiles by using the antibiotic concentration gradient method. The study was performed in Afyon Kocatepe University Ahmet Necdet Sezer Research and Practice Hospital, Medical Microbiology Laboratory between 1 November 2014 and 30 October 2015. Two hundred and seventyeight clinical specimens accepted for anaerobic culture were enrolled in the study. All the samples were cultivated anaerobically by using Schaedler agar with 5% defibrinated sheep blood and Schaedler broth. The isolated anaerobic gram-negative bacilli were identified by using both the conventional methods and automated identification system (VITEK 2, bioMerieux, France). Antibiotic susceptibility tests were performed with antibiotic concentration gradient method (E-test, bioMerieux, France); against penicillin G, clindamycin, cefoxitin, metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem for each isolate. Of the 28 isolated anaerobic gram-negative bacilli; 14 were identified as Bacteroides fragilis group, 9 were Prevotella spp., and 5 were Fusobacterium spp. The highest resistance rate was found against penicillin (78.5%) and resistance rates against clindamycin and cefoxitin were found as 17.8% and 21.4%, respectively. No resistance was found against metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem. As a result, isolation and identification of anaerobic bacteria are difficult, time-consuming and more expensive when compared with the cost of aerobic culture. The rate of anaerobic bacteria isolation may be increased by obtaining the appropriate clinical specimen and appropriate transportation of these specimens. We believe that the data obtained from the study in our center may offer benefits for the follow up and treatment of infections caused by anaerobic bacteria and may contribute to the current literature. Because of high resistance rate detected against penicillin, this antibiotic should not be used as a first choice in empirical treatment. Cefoxitin may be used in empirical antimicrobial treatment of anaerobic gram-negatives; but the rate of antibiotic resistance should be detected for more useful and proper treatment. The prior selection of the most effective antibiotic, may contribute to decrease the rate of high resistance. In our study, no resistance was observed against carbapenem group antibiotics and metronidazole; so these antibiotics should be reserved as treatment options in the future for infections caused by resistant gram-negative anaerobic bacteria.

Nodular lymphocyte predominant Hodgkin's lymphoma in daily practice: A multicenter experience.

Nodular lymphocyte predominant Hodgkin's lymphoma (NLPHL) is a rare subtype of Hodgkin's lymphoma. In this study, we aimed to investigate the clinical features and therapeutic outcomes of patients with NLPHL who were diagnosed at different institutes in Turkey. We retrospectively reviewed the records of the patients diagnosed with NLPHL. Adult patients who were diagnosed after 2005 with histological confirmation were selected for the study. Forty-three patients were included in the study. Median age of patients was 37.5 years (18-70) at the time of diagnosis. About 60.5% patients were diagnosed as stage I and II NLPHL, and remaining 39.5% had stage III and IV disease. Median follow-up was 46 months. During follow-up, none of the patients died. Seven patients relapsed or progressed after initial therapy at a median of 12 months. Five of 7 relapsed/refractory patients (71.4%) were salvaged with chemotherapy only (DHAP, ICE), and the remaining 2 (28.6%) were salvaged with chemoimmunotherapy. All of relapsed/refractory patients were able to achieve complete remission after salvage therapy. Lactate dehydrogenase levels were significantly higher in patients with progressive disease compared with nonprogressive disease. Our study showed an excellent outcome with all patients alive at last contact with a median follow up of 46 months despite a wide range of different therapeutic approaches. All relapsed and refractory patients were successfully salvaged despite a low frequency of patients received immunotherapy in conjunction with chemotherapy. Our results suggest that immunotherapy may be reserved for further relapses.

Clinical and serological autoimmune complications in chronic lymphocytic leukemia.

BACKGROUND: Autoimmune disorders often develop during the course of chronic lymphocytic leukemia (CLL). The aim of our study was to investigate the incidence of autoimmune complications (AIC) and serological autoantibodies, and to assess the relationship of these to patient characteristics. METHODS: We prospectively collected screenings of AIC and serological markers from a total of 192 patients. RESULTS: AIC was observed in 18 (9.4%) patients. Autoimmune hemolytic anemia (AIHA) was observed in 8 patients. Autoimmune thrombocytopenia (AITP) was observed in 3 patients. Other various types of AIC were observed in the remaining 7 patients. Serological autoantibodies were positive in 17.2% of patients with CLL. The mean age of patients with AIC was higher than the control group (p = 0.036). Patients with AIC were mostly in advanced disease stage (p = 0.004), and they had received more first-line treatments than the control group (p = 0.003). Patients with AIC had a higher mean age and more advanced disease stage than patients with positive serological autoantibodies (p = 0.020 and p = 0.009; respectively). In addition, patients with AIC had also received more first-line treatment than the patients with positive serological autoantibodies (p = 0.015). Hematologic AIC was associated with older age, advanced disease stage, and treatment. Conversely, non-hematological AIC and serological autoantibodies are generally observed in early stages. CONCLUSIONS: Our study has established a coexistence of CLL and autoimmune complications. Hematologists are usually familiar with AIHA and AITP, but less so with non-hematologic AIC. The latter complications should be carefully searched for, particularly in patients with early CLL.

Clinical and Laboratory Features of CD5-Negative Chronic Lymphocytic Leukemia.

BACKGROUND Chronic lymphocytic leukemia (CLL) usually expresses CD5 antigen. However, 7-20% of patients are CD5 negative. We report here a series of 19 CD5-negative B-CLL cases. MATERIAL AND METHODS We reviewed 19 consecutive CD5-negative B-CLL cases seen in our medical center from 2009 to 2015 and compared them with 105 CD5-positive B-CLL cases. The two groups were compared in terms of clinical parameters, laboratory parameters, and survival characteristics. RESULTS Lymphadenopathy was present in 31.5% of the CD5-negative group and 51.4% of the CD5-positive group (p=0.029). Splenomegaly was present in 42.1% of the CD5-negative group and 16.1% of the CD5-positive group (p=0.029). There was no difference between the groups in terms of Binet A, B, and C stages (p=0.118, p=0.051, and p=0.882, respectively). The median thrombocyte count was 144×109/L and 160×109/L in the CD5-negative and CD5-positive groups, respectively (p=0.044). There was no difference between the two groups in terms of median neutrophil count (p=0.169). The mean lymphocyte count was 43.2±4.0×10^9/L and 36.7±3.2×10^9/L in the CD5-negative and CD5-positive groups, respectively (p=0.001). There was no difference between the groups in terms of autoimmune hemolytic anemia and autoimmune thrombocytopenia. In five-year follow-up, 84.2% of CD5-negative patients and 90.5% of CD5-positive patients were alive (p=0.393). CONCLUSIONS We found more isolated splenomegaly, less lymphadenopathy, a higher lymphocyte count, and a lower thrombocyte count in the CD5-negative group. There was no difference between the groups in terms of clinical stage, autoimmune phenomena, hemoglobin and neutrophil count, and survival.

Primary central nervous system lymphoma in daily practice and the role of autologous stem cell transplantation in relapsed disease: A retrospective multicenter study.

We investigated the course of 54 patients presenting with primary central nervous system lymphoma, who were treated in daily practice. The patients were treated with chemotherapy and/or radiotherapy and/or intrathecal chemotherapy. At a median follow-up period of 23 months (range 1-71), median relapse-free survival (RFS) and overall survival (OS) were not reached. Estimated 2-year RFS and OS rates were 42% and 48%, respectively. Ten relapsed PCNSL patients underwent ASCT. Complete remission rate of these patients was 40%, with 20% treatment-related mortality. Estimated 2-year RFS and OS rates were 37% and 40%, respectively. The prognosis of patients with PCNSL, who received off-study treatment, is still dismal.

[Molecular epidemiology of beta-lactamases in ceftazidime-resistant Pseudomonas aeruginosa isolates]. / Seftazidime dirençli Pseudomonas aeruginosa izolatlarinda beta-laktamazlarin moleküler epidemiyolojisi.

Pseudomonas aeruginosa is an important opportunistic pathogen that cause mainly nosocomial infections especially in the immunocompromised patients, the elderly and patients with severe burns. The bacterial feature of developing high degree of resistance against several antibiotics leads to increased morbidity and mortality of P.aeruginosa infections. The aims of this study were to investigate the antibiotic susceptibilities of P.aeruginosa strains isolated from hospitalized patients and to determine the presence of resistance enzymes namely PER, GES, KPC, VIM, IMP and OXA. A total of 195 P.aeruginosa strains isolated from different clinical samples (29 sputum, 67 wound, 53 tracheal aspirate, 23 blood, 18 urine, 3 cerebrospinal fluid, 2 pleural fluid) of inpatients (134 male, 61 female) in Afyon Kocatepe University School of Medicine Hospital between 2010-2012, were included in the study. The isolates were identified by conventional methods and automated systems (VITEK 2, BioMerieux, France), and their antibiotic susceptibilities were detected by disk diffusion and E-test methods. Inducible beta-lactamase (IBL), extended-spectrum beta-lactamase (ESBL) and metallo-beta-lactamase (MBL) productions of the isolates were phenotypically investigated by double disk induction, double disk synergy and E-test methods, respectively. The presence of resistance genes encoding PER, GES, KPC, VIM, IMP and OXA enzymes were determined by real-time polymerase chain reaction, and sequence analysis was applied to positive samples. In our study, the antibiotic resistance rates of 195 P.aeruginosa strains were found as follows: ceftazidime 100%, tazobactam/piperacillin 90.8%, aztreonam 60.5%, cefepime 50.2%, imipenem 48.2%, meropenem 47.2%, ofloxacin 47.2%, piperacillin 44.1%, levofloxacin 31.3%, ciprofloxacin 26.2%, gentamicin 11.8%, amikacin 8.7% and tobramycin 6.2%. With the use of phenotypical methods, IBL, ESBL and MBL production rates in the isolates were detected as 89.2% (174/195), 30.7% (60/195) and 26.7% (52/195), respectively. Molecular studies showed that, five strains harboured OXA-10, four OXA-14, four VIM-2, two IMP-1, 26 GES-1 and 87 ABC transporter permease genes, while PER and KPC genes were not detected in any of the isolates. In conclusion, it was considered that the detection of beta-lactamase genes in bacteria and the identification of beta-lactamase types may provide facilities in selection of antibiotics, monitorization of therapy, prevention of resistance development of infection control programs.