Comparison in a rat thigh abscess model of imipenem, meropenem and cefoperazone-sulbactam against Acinetobacter baumannii strains in terms of bactericidal efficacy and resistance selection

BACKGROUND: We compared imipenem, meropenem and cefoperazone-sulbactam against hospital originated A. baumannii strains in terms of bactericidal efficacy and selection of resistant mutants during treatment in a rat thigh abscess model. METHODS: A total of 18 strains were inoculated in 54 animals (one strain for three animals). Randomly selected 10 among these 18 strains were inoculated in another 10 rats as the control group. Imipenem, meropenem and cefoperazone-sulbactam were the antibiotics compared. After four days of treatment, Wistar albino rats (200 to 250 g) were sacrificed and the abscess materials were processed for mean colony counts and for the presence of resistant mutants. RESULTS: The mean CFUs per gram (mean ± (std. deviation) [×10(4)]) of the abscess were: 9,14 (25,24), 2,11 (3,78), 1,20 (1,70) in the imipenem (n = 17), meropenem (n = 18) and cefoperazone-sulbactam (n = 17) groups, respectively. The differences were not significant. On the other hand, no resistant mutant was detected in abscess materials. CONCLUSION: This study indicated; first, cefoperazone-sulbactam is comparable to carbapenems in bactericidal efficacy in this particular abscess model and second, emergence of resistance due to spontaneous mutations is not at least a frequent phenomenon among A. baumannii

Investigation of levels of adenosine, deaminase, and subtle interleukin-2 in cerebrospinal fluid in purulent, tuberculosis and viral meningitis

Tıp dünyasında tüm teknolojik ilerlemelere rağmen menenjitlerin ayırıcı tanısı hala büyük bir problemdir.özellikle beyin omurilik sıvısında (BOS) düşük sayıda hücresi olan pürülan menenjit (PM), başlangıç dönemindeki viral menenjit (VM) ile 1 tüberküloz menenjit (TBM) sıklıkla karışmaktadır.Çalışmamızda t beyin omurilik sıvısında adenosin deaminaz (ADA) aktivitesi ile solübl interlökin-2 reseptör (sIL-2R) düzeylerini ölçtük.ADA enzimi pürin katabolizmasında rolü olan bir enzimdir.T lenfositlerde saptanmıştır.sIL-2R T ve B hücre aktivasyonu sonucunda oluşan ve patogenezinde hücresel immünitenin rol oynadığı birçok hastalıkta artan bir moleküldür. Menenjit olgularında her iki testin, TBM'in VM'ten ayırd edilmesinde çok yararlı olduklarını saptadık. Bazı olgularda PM ile TBM' deki BOS değerlerinin üst üste çakışması nedeniyle bu iki menenjitin ayırd edilmesinde ek parametrelerin de dikkate alınarak değerlendirme yapılmasının faydalı olacağı kanaatindeyiz

Investigation of Tularemia Incidence and Presence of Francisella tularensis in Streams/Mains Water in a Risky Region of Thrace

WOS: 000464106600016Objective: Tularemia was first detected in Thrace region in our country and the outbreaks continued in the region over the following years. The fact that the agent has been identified in mice around Kaynarca in 2012 suggests the disease poses a risk for our region. Aim of this study was to investigate tularemia incidence and presence of Francisella tularensis in streams/mains water in a risky region of Thrace. Methods: In this study, seropositivity for tularemia was investigated in 13 villages, and 1 town in risky areas of the Thrace region. In January 2016, blood was drawn from 746 people and tularemia microagglutination tests were applied. Seropositivity was not detected. In December, 464 of 746 people were reached. Seroconversion was not observed. In addition, culture and polymerase chain reaction (PCR) procedures were applied to specimens collected from mains water and streams in 13 villages and 1 town. Results: The causative agent wasn't isolated from the cultures but F. tularensis DNAs were detected by PCR method in 2 stream, and 3 mains water samples. One of the streams passed through the village of Celaliye, which was very close to Kaynarca, where tularemia cases were seen in the past. The other was farther, passing through the Kavakli town in which no cases has been reported. The mains water which were positive were from Hamzabey, Ceylankoy, and Tatarkoy villages located around Kaynarca. Molecular examination after chlorination was repeated in the water sources in which positivity was detected, and it was seen that the agent was eliminated. Conclusions: In this study, incidence was calculated as zero, although the causative agent was found in the water. Although no seropositivity was detected, the detection of the agent by PCR in 5 water samples showed that the agents in the nature could reach the water resources. It has been observed that surveillance studies in risky areas could be effective in preventing possible outbreaks

Evaluation of Resistance Transfer by Conjugation, in Escherichia coli, Klebsiella and Salmonella Species, on Solid Phase at Different Temperatures

Conjugation means transfer of genetic material via bacterial membranes. Fimbrial characters that are responsible for this transfer are coded by conjugative plasmids that multiply in the cytoplasm. This transfer efficiency may be different in solid, liquid phases or on membranes. Conjugation in some of the members of Enterobacteriaceae family is also temperature dependant. This study was carried out to determine the optimal temperature and donor-acceptor ratios for transconjugation in Escherichia coli, Klebsiella and Salmonella species which belong to Enterobacteriaceae family. Fifteen strains, five from each of these species that mentioned above, which were determined to be multiresistant, were introduced to standart recipient E. coli J53-2 in two different concentration [(a) donor:recipient ratio 4:1; and (b) donor:recipient ratio is 1:4] and three different temperatures 32°C, 37°C and 42°C. “Multivariate” analysis was done with “repeated measures one way ANOVA test” whereas “univariate” analysis was done with “Wicoxon Sign Rank” tests. The results of these two tests correlated well and the results were found to be statistically different. In conclusion, transconjugation on solid phase was found to be optimal for group (b) where the recipient:donor ratio was 4:1 and the temperature was 37°C

Microbiological Approach to a Possible Infective Endocarditis Case Caused by Aggregatibacter actinomycetemcomitans

Aggregatibacter (Actinobacillus) actinomycetemcomitans, a small, gram-negative coccobacillus that grows slow and fastidious, is generally colonized in the oral cavity. It is a rarely seen bacterium because of the difficulty of isolation but it can be a causative agent for dental infections and infective endocarditis (IE) particularly in the persons having prosthetic heart valves. In this report, a possible IE case caused by A.actinomycetemcomitans in a patient with aortic valve replacement has been presented. A 36-year-old man has admitted to Trakya University Hospital, Health Center for Medical Research and Practice, with the complaints of chills, malaise, intermittent fever, severe arthralgia and weight loss (20 kg). During his follow-up period, the blood cultures that were obtained three week intervals yielded the identical gram negative coccobacilli morphology. The patient was then diagnosed as possible IE on the basis of having one major (growth of the typical microorganisms that may cause IE in two different blood cultures) and two minor (presence of prosthetic valve and high fever) criterias. The isolate could not be identified with conventional methods, while it was identified as Francisella tularensis with VITEK 2 (bioMerieux, France) system. Hence this identification was not confirmed by real-time Taqman polymerase chain reaction, so MALDI-TOF mass spectrometry was used to identify this bacteria. In the first run of the study, the isolate was named as Shigella dysenteriae initially, however when it was retested the next day it was identified as A.actinomycetemcomitans. In order to enlighten these conflicting results, 16S and 23S ribosomal DNA sequence analysis was performed, and consequently the bacterium was identified as A.actinomycetemcomitans. Doxycycline (2 x 100 mg po, 20 days) and streptomycin (2 x 10 mg/kg im, 10 days) therapy were initiated, considering the initial suspicious identification (F.tularensis), and on the fifth day of therapy the blood culture was negative with the regression of patient's complaints. Therapy continued with the addition of rifampicin to doxycycline from the 21(st) day and the patient discharged with cure. As a result, the identification of an exceptional bacterium like A.actinomycetemcomitans may be difficult and time-consuming in certain laboratory facilities. So, the use of different identification methods in addition to classical methods are needed to overcome such a problem, especially for uncommon isolates and clinically discordant cases. This case was presented because A.actinomycetemcomitans is a rare etiological agent for IE patients and it could be a good example to draw attention to the problem when identifying the organism using automatized identification systems

Genişlemiş Spektrumlu Beta Laktamaz Üreten Escherichia coli'nin Neden Olduğu Üriner Sistem İnfeksiyonlarında Aynı Etkenin Dışkıda Taşıyıcılığının Saptanması: Araştırma Makalesi

Introduction-Objective: We aimed to determinate the risk factors, contribution of fecal carriage to the infection and precautions to be taken in the prevention of infection in (+) E. coli-induced UTIs in urinary tract infections (UTI) caused by ESBL (+) E. coli Method: This study was designed as a single-center, prospective and cross-sectional. 64 patients between the ages of 18-79 who were hospitalized and ESBL(+) E.coli isolated in their urine culture were included. Stool samples taken from the patients (0,3,5 and 7 days) were inoculated on EMB agar containing cefotaxime and ceftazidime and IMVIC was used to identify colonies. Strains determined as E. coli according to their reproductive characteristics were included in the study. Phenotypic confirmation tests for the detection of ESBL(+) strains. Genotyping was performed using the ERIC PCR method. Descriptive statistics were expressed as numbers and percentages. Chi-square and trend chi-square tests were used for analytical comparisons. A P value of <0.05 was considered statistically significant. Results: Of the 64 patients 40 (62.5%) were female and the mean age was 56.5 ± 17.5 (18-79). 47 (69%) were diagnosed with CA- UTI, and 17 (31%) with HA-UTI. Having more than three episodes per year and presence of a foreign device were found to be a risk factor for CA- ESBL (+) E. coli-induced UTI (p:0.035and 0.006). It was found that faecal colonization of ESBL (+) E. coli persisted in 15 (23%) of 64 patients after UTI treatment, and, of them 20% (n: 3) was in the same phylogenetic class with the ERIC PCR method. Faecal colonization was found to be significantly higher in patients with invasive intervention in the previous year (p:0.037). Conclusion: Unnecessary antibiotic use should be avoided due to resistant infections and increased colonization. The importance of fecal colonization in infections with ESBL-producing bacteria (especially UTI) has been demonstrated in studies. More prospective studies are needed to understand the epidemiology of ESBL enzyme types.Giriş-Amaç: GSBL (+) E. coli’nin neden olduğu ÜSİ’de aynı etkenin dışkı kolonizasyonunun ve hem idrar hem de dışkı izolatlarından elde edilen fenotipik olarak benzer etkenlerin moleküler olarak birbirleriyle benzerliklerinin araştırılması ve GSBL (+) E. coli kaynaklı ÜSİ’ lerde risk faktörleri, fekal taşıyıcılığın infeksiyona katkısı ve infeksiyonun önlenmesinde alınması gereken önlemlerin belirlenmesi amaçlanmıştır. Yöntem: Tek merkezli, ileriye dönük, kesitsel çalışmada idrar kültüründe GSBL üreten E.coli izole edilen, 18-79 yaş aralığında 64 hasta çalışmaya dahil edildi. Hastalardan alınan dışkı örnekleri sefotaksim ve seftazidim içeren içeren EMB agara ekildi ve Enterobacteriaceae ailesine ait kolonilerin identifikasyonunda IMVIC testi kullanıldı. Üreme özelliklerine göre E. coli olarak belirlenen suşlar çalışmaya alındı. GSBL taşıyan kökenlerin tespiti için fenotipik doğrulama testleri ve DNA izolasyonu için ERIC PCR yöntemi kullanıldı.Tanımlayıcı istatistikler sayı ve yüzde olarak ifade edildi. Analitik karşılaştırmalar için ki-kare ve trend ki –kare testleri kullanıldı. p<0.05 değeri istatistiksel olarak anlamlı kabul edildi. Bulgular: 64 hastanın 40’ı (%62.5) kadın ve yaş ortalaması 56.5 ± 17.5 (18-79) idi. Hastaların 47 (%69)’ si TK 17 (%31)’ si ise HK-ÜSİ tanısı almıştı.Yılda üçten fazla ÜSİ atağı geçirmek ve yabancı cisim bulunması TK- GSBL (+) E. coli’ ye bağlı ÜSİ için risk faktörü olarak bulunmuştur (p:0.035 ve 0.006). 64 hastanın 15 (%23)’inde ÜSİ tedavisi sonrası GSBL (+) E. coli’nin fekal kolonizasyonunun persiste ettiği ve bunların üç (%20)’ ünün dışkı ve idrar izolatlarının aynı filogenetik sınıfta olduğu bulunmuştur. Son bir yılda invazif girişim varlığı olanlarda fekal kolonizasyon anlamlı olarak yüksek saptanmıştır (p:0.037). Sonuç: Dirençli infeksiyonlar ve kolonizasyon artışı nedeni ile gereksiz antibiyotik kullanımı önlenmelidir. GSBL üreten bakterilerle meydana gelen infeksiyonlarda fekal kolonizasyonun önemi ve GSBL enzim tiplerinin epidemiyolojisinin anlaşılabilmesi için ileriye dönük daha büyük çalışmalara ihtiyaç vardır