Mustafa Berktaş

Change in Serum Concentrations of Interleukin-2 and Interferon-γ during Treatment of Tuberculosis

We aimed to investigate changes in serum concentrations of the cytokines interleukin (IL)-2 and interferon (IFN)-γ during the clinical course of active tuberculosis, to establish the presence of cellular immunity before and after treatment. Blood samples were taken from 18 patients with active tuberculosis before and 2 months after therapy; IL-2 and IFN-γ concentrations were evaluated. The mean serum IL-2 concentration before therapy was 164.5 pg/ml (range 12–980 pg/ml) and the concentration 2 months after therapy was 92.11 pg/ml (range 1–490 pg/ml). The mean serum IFN-γ concentrations were 10.83 pg/ml (range 1–22.2 pg/ml) and 4.64 pg/ml (range 1–28.5 pg/ml), respectively. The decrease in concentrations of both cytokines after therapy was statistically significant. Further studies investigating the benefits of adding cytokines to drug treatment for tuberculosis are needed.

Identification and Determination of Antibiotic Susceptibilities of Brucella Strains Isolated from Patients in Van, Turkey by Conventional and Molecular Methods

Purpose: Brucellosis is a worldwide zoonotic disease and still constitutes a major public health problem. In this study, we aimed to identify biovars of Brucella strains isolated from clinical specimens taken from brucellosis patients from the Eastern Anatolia region as well determine the susceptibility of these isolates to tigecycline and azithromycin, drugs that may serve as alternatives to the conventional drugs used in the therapy. Materials and methods: Seventy-five Brucella spp. isolates were included in the study. All strains were identified by both conventional and molecular methods. Brucella Multiplex PCR kit (FC-Biotech, Code: 0301, Turkey) and B. melitensis biovar typing PCR kit (FC-Biotech, Code: 0302, Turkey) were used for molecular typing. Antimicrobial susceptibilities of all strains were determined by E-tests. Results: By conventional biotyping, 73 strains were identified as B. melitensis biovar 3 and two strains as B. abortus biovar 3. Molecular typing results were compatible with conventional methods. The MIC50 and MIC90 values of doxycycline were 0.047 and 0.094; tigecycline 0.094 and 0.125; trimethoprim/sulfamethoxazole 0.064 and 0.19; ciprofloxacin 0.19 for both; streptomycin 0.75 and 1; rifampin 1 and 2 and azithromycin 4 and 8. According to the MIC values, doxycycline was found to be the most effective antibiotic, followed by tigecycline, trimethoprim-sulfamethoxazole and ciprofloxacin. Conclusion: Currently recommended antibiotics for the treatment of brucellosis such as doxycycline, rifampin, streptomycin, trimethoprim-sulfamethoxazole and ciprofloxacin were found to be still effective. While our results showed that tigecycline can be used an alternative agent in the treatment of brucellosis, azithromycin has not been confirmed as an appropriate agent for the treatment.

Correlation of Slime Production Investigated via Three Different Methods in Coagulase-Negative Staphylococci with Crystal Violet Reaction and Antimicrobial Resistance

This study investigated slime production by coagulase-negative staphylococci (CNS) using the standard tube (ST), Congo red agar (CRA) plate and Christensens tube (CT) methods, and compared the results with those of the crystal violet reaction (CVR) test. The potential correlation between slime production and antimicrobial resistance was also evaluated. In total, 205 CNS strains were isolated from biological samples: 92 (44.9%) were shown to produce slime by the ST method; 96 (46.8%) by the CRA plate method; 90 (43.9%) by the CT method; and 89 (43.4%) strains were CVR positive. Eighty-three (40.5%) CNS strains were positive for slime production by the ST, CRA and CT methods. The findings of the ST, CRA and CT test methods were consistent with each other but were not related to CVR positivity. Based on the ST method, rates of antibiotic resistance to several antimicrobial agents were higher in slime-positive strains than in slime-negative strains and, in some cases, this was statistically significant.

Antibiotics resistance of Stenotrophomonas maltophilia strains isolated from various clinical specimens

BACKGROUND A limited number of antibiotics are recommended for the therapy of Stenotrophomonas maltophilia infections due to therapy difficulties caused by its numerous mechanisms of resistance. OBJECTIVES In this study conducted over a period of approximately 5 years we aimed to determine resistance rates of S. maltophilia based on drug classification recommended by Clinical and Laboratory Standards Institute. METHODS A total of 118 S. maltophilia strains isolated from various clinical specimens between January 2006 and June 2012 were included in the study. BD Phoenixautomated microbiology system (Becton Dickinson, USA) was utilized for species level identification and antibiotic susceptibility testing. RESULTS Sixty seven of S. maltophilia strains were isolated from tracheal aspirate isolates, 17 from blood, 10 from sputum, 10 from wound and 14 from other clinical specimens. Levofloxacin was found to be the most effective antibiotic against S. maltophilia strains with resistance rate of 7.6%. The resistance rates to other antibiotics were as follows: chloramphenicol 18.2%, trimethoprim-sulfamethoxazole 20.3% and ceftazidime 72%. CONCLUSION The study revealed that S. maltophilia is resistant to many antibiotics. The treatment of infections caused by S. maltophilia should be preferred primarily as levofloxacin, chloramphenicol, and TMP-SXT, respectively.

Distribution of hepatitis C prevalence in individuals according to their age level in Eastern Turkey.

Hepatitis C virus (HCV) belongs to the Flaviviridae virus family. Its reservoir is the human being. HCV is highly transmittable and is usually transmitted through blood transfusion, use of the same syringe between drug users, during sexual interaction and from mother to child. The course of HCV infection can develop subclinically without any clear symptoms. More than 50% of patients, however, develop chronic hepatitis, and subsequently a high percentage of these patients develop cirrhosis [1,2].

Detection of putative virulence genes in Aeromonas isolates from humans and animals

INTRODUCTION Aeromonas are food- and water-borne bacteria that are considered to be zoonotic human pathogens. This study aimed to investigate the presence of genes associated with virulence in human and animal Aeromonas isolates and the potential role of animal isolates with regards to human Aeromonas infections. METHODOLOGY The presence of aerA, hlyA, alt, ast, laf, ascF-G, stx1 and stx2 putative virulence genes in 40 human and animal Aeromonas isolates (16 human and 24 animal isolates) were examined by polymerase chain reaction (PCR). DNA fragments of expected sizes were purified and sequenced. BLAST in the NCBI was used to verify any amplified products. RESULTS PCR screening showed that hlyA, alt, and laf genes were determined at ratios of 6.25%, 50%, and 6.25%, respectively, in human isolates. The ratios of hlyA, alt, ascF-G, laf, stx2, and stx1 genes in animal isolates were 58.3%, 20.83%, 33.3%, 20.83%, 8.33%, and 4.17%, respectively. Neither aerA nor ast genes were detected in any isolates. Any one of eight putative virulence genes was not detected in seven human and eight animal isolates in the study. CONCLUSIONS The current study is the first to investigate the presence of the virulence gene in gull Aeromonas isolates. The manifestation of the presence of the virulence gene and gene combinations was considerable, especially in fish and gull isolates when compared with clinical human isolates. The current study demonstrates the potential importance of fish and gulls in terms of human Aeromonas infections.

vanC Gene-Related Intrinsic Teicoplanin Resistance Detected in Enterococcus casseliflavus and E. gallinarum Strains by the BD Phoenix Automated Microbiology System

Enterococcus members are becoming increasingly important agents of human disease, largely because of their resistance to antimicrobial agents. Because of their resistance to penicillins and cephalosporins of several activity ranges, the acquisition of high-level resistance to aminoglycosides, and now the emergence of vancomycin resistance, these bacteria are often involved in serious superinfections among patients receiving broad-spectrum antimicrobial chemotherapy (2). Acquired glycopeptide resistance in Enterococcus species corresponds to five different phenotypes, with VanA and VanB phenotypes being the most prevalent and important clinically. Strains with the vanA genotype characteristically display inducible, transposon-mediated, high-level resistance to both vancomycin (MIC, 64 to 1,000 μg/ml) and teicoplanin (MIC, 16 to 512 μg/ml). Strains with the vanB genotype have acquired inducible resistance to various concentrations of vancomycin (MIC, 4 to 1,000 μg/ml) but remain susceptible to teicoplanin (MIC, 0.5 to 1 μg/ml), although rare vanB strains may also be resistant to the latter antibiotic. Isolates that have the vanC genotype display intrinsic, constitutive, low-level resistance to vancomycin (MIC, 2 to 32 μg/ml) and are susceptible to teicoplanin (MIC, 0.5 to 1 μg/ml). The vanC genotype corresponds to the intrinsic glycopeptide resistance seen in Enterococcus gallinarum, E. casseliflavus, and E. flavescens (2). The antibacterial activities of teicoplanin against gram-positive bacteria, including those expressing resistance to unrelated compounds, are similar to that of vancomycin, but with increased potency, particularly against Streptococcus spp. and Enterococcus spp. Teicoplanin is active against vancomycin resistance caused by VanB and VanC but is not active against VanA resistant strains. Despite the increasing importance of glycopeptide resistance, teicoplanin has proved its clinical worth and continues to have important potential in the treatment of life-threatening gram-positive sepsis (1a). Automated microbiology systems are routinely used for identification and antimicrobial susceptibility testing of a wide spectrum bacteria, including those of the Enterococcus genus. The Phoenix Automated Microbiology System (Becton Dickinson) is one of these systems used in our microbiology laboratory at Yuzuncu Yil University Medical Faculty Hospital. Recently, E. casseliflavus and E. gallinarum strains were isolated from two different urine samples from a patient, and teicoplanin was reported as resistant, although the MIC was ≤1. Upon examination of the preliminary reports, a change from sensitive to resistant for teicoplanin by the automated BDXpert system in accordance with rule 1099 of that system was observed (1). Rule 1099 under the expert trigger rules states that “E. casseliflavus or E. gallinarum is intrinsically low-level resistant to vancomycin and teicoplanin (VanC),” and because of the identified bacteria, the exchange for teicoplanin from sensitive to resistant was made following this rule. Resistance to teicoplanin in Enterococcus species is often seen in E. faecalis and E. faecium strains due to the vanA gene. Identification and antibiotic susceptibility tests for both of the two isolated strains were repeated in order to prevent any misidentifications, but there was not any change in the results. Antimicrobial testing of teicoplanin by use of the Kirby-Bauer disc diffusion method was performed on both of the isolated strains, and they were both detected as sensitive to teicoplanin. E. casseliflavus and E. gallinarum strains have the chromosomal nontransferable vanC gene, and they are intrinsically low-level resistant to vancomycin; however, they are sensitive to teicoplanin. Researchers in clinical microbiology laboratories using automated systems for antimicrobial susceptibility tests should be aware of this situation, and the result needs to be verified using a reference method before reporting the isolate as resistant to teicoplanin.

Distribution, Optimum Detection Time and Antimicrobial Susceptibility Rates of the Microorganisms Isolated from Blood Cultures over a 4-Year Time Period in a Turkish University Hospital and a Review of the International Literature

This study retrospectively examined 8986 blood cultures from patients over a 4-year time period in an eastern Turkish university hospital to determine the detection times and distribution of isolated microorganisms using the automated BACTEC™ 9050 and BACTEC™ 9120 systems. A total of 1914 (21.3%) blood cultures contained pathogenic microorganisms and 252 (2.8%) positive cultures were considered contaminated. Of all the cultures, 18 (0.2%) were false positives and 224 (2.5%) were false negatives. In cultures containing pathogenic microorganisms, Gram-positive and Gram-negative bacterial isolation rates were 436 (22.8%) and 1440 (75.2%), respectively, and yeasts (all Candida sp.) were found in 38 (2.0%) cultures. Coagulase-negative staphylococci occurred in 936 (48.9%) cultures and Staphylococcus aureus occurred in 302 (15.8%) cultures. The mean detection time for all of the pathogens was 21 h and Brucella spp were isolated within 10 days. This study helps in understanding the epidemiology of the region and in providing positive therapeutic approaches. A review of the international literature helps to place this understanding into a global context.

Türkiye\'nin Van yöresinde Anti-HAV IgM pozitifliğinin yaş ve aylara göre dağılımı

Objectives: In this study we investigated the anti-HAV IgM positivity rates and their distribution according to age and season of a year in Van region of Turkey. Materials and methods: During five-year period be tween 2006-2010, the presence of anti-HAV IgM were determined in the serum samples sent to our laboratory that have prediagnosis of hepatitis A by ELISA test, using AxSYM (Abbott Diagnostics, Germany) and i2000SR Architect (Abbott Diagnostics, Germany) analyzers. For statistical analyze of Anti-HAV IgM positivity rates, patients’ age and gender and time of year when specimen was obtain were compared. Results: The presence of anti-HAV IgM was investigated in a total of 8851 patients, including 5303 (60%) children and 3548 (40%) adults. Anti-HAV IgM in children and adult patients were determined as 9.8% and 2.6%, respectively, and this difference was found statistically significant (p <0.01). Anti-HAV IgM positivity rate began to rise in August, reached the highest level in November-December and decreased to the initial level in January. The highest frequency detected during the November-December period was statistically significantly higher than rates found during other months. Conclusions: The prevalence of Hepatitis A was found to be similar with previous studies performed in our country. The prevalence of disease was significantly increased es pecially between November and December.

Seroprevalence of Crimean-Congo Hemorrhagic Fever in Turkey's Van Province

Crimean-Congo hemorrhagic fever (CCHF) is an endemic tick-borne viral disease that affects both animals and humans. This study aims to determine the seroprevalence of CCHF in Turkeys Van province using analysis of blood samples obtained from people living in the region. Blood specimens were taken from healthy subjects living in Van province and some of the surrounding villages between January and July 2012. Blood samples were initially tested using a CCHF virus (CCHFV) IgM IgG kit for anti-CCHFV IgG, followed by anti-CCHFV IgM determination of any IgG positive blood samples. IgM-positive specimens were re-confirmed using real-time polymerase chain reaction (qPCR). One hundred and 7 men and 261 women were included in the study. Fifty-three blood specimens (14.4%) were anti-CCHFV IgG positive, and 2 of these were anti-CCHFV IgM positive. Two blood samples with anti-CCHFV IgM seropositivity tested negative using qPCR, indicating chronic infections. Locality, sex, and a history of tick bites did not significantly affect anti-CCHFV IgG seropositivity. Although the incidence of anti-CCHFV IgG in blood specimens was 14.4%, no deaths have yet been reported in Turkeys Van province. It is imperative that clinical CCHFV tests be implemented for people at high risk of developing CCHFV-related complications.