Retrospective Evaluation of Toxoplasma gondii Serological Test Results of Trakya University Health Center for Medical Research and Practice

Objective: Toxoplasma gondii (T. gondii) is an obligate intracellular parasite distributed worldwide. Serological tests investigating antibodies specific to T. gondii are widely used in diagnosis. The aim of this study was to evaluate the results of anti-T. gondii IgG, anti-T. gondii IgM, and anti-T. gondii IgG avidity tests, which were sent to the Serology Laboratory of Trakya University Health Center for Medical Research and Practice, retrospectively. Methods: Anti-T. gondii IgM, anti-T. gondii IgG, and anti-T. gondii IgG avidity tests were studied by enzyme-linked fluorescent assay or electrochemiluminescence immunoassay method between January 2012 and December 2021. The test results were evaluated retrospectively from laboratory records. Results: Of 18,659 serum samples were studied for anti-T. gondii IgG, 5,127 (27.5%) samples were positive, whereas 721 (3.4%) of 21,108 samples were positive for anti-T. gondii IgM. Of the 593 serum samples tested for IgG avidity, 206 (34.7%) samples had low avidity, 118 (19.9%) had borderline, and 269 (45.4%) had high avidity. Conclusion: Our study, compatible with other studies, showed that seropositivity is high in our region, which is not negligible. Especially in women of reproductive age population, T. gondii should be considered in suspected clinical cases.

Tularemia seroprevalence in humans in the region of the Hittite-Arzawa War (Inner Aegean Region), where the first biological weapon was used 3300 years ago.

BACKGROUND: : According to Egyptian records, tularemia emerged in the Canaan region, where it was first identified and spread to Anatolia over the Euphrates. It was used as an active biological weapon for the first time in the Hittite-Arzawa War in 1320-1318 BC. This study aimed to investigate the seroprevalence of tularemia in the Inner Aegean Region, which is thought to be the region where this war was fought 3300 years ago. METHODS: Tularemia seropositivity in humans was investigated in 27 villages/neighborhoods in 3 districts in each of Manisa, Kütahya, and Usak provinces. Before the study, the participants were informed about the disease via posters, and their blood samples were taken following filling out the questionnaire. Microagglutination tests were performed using in-house tularemia antigen and V plate for serological experiments. Rose-Bengal test was also performed on seropositive sera. RESULTS: Of the total of 410 people, 226 (55.12%) were male. The mean age of the volunteers was 43.72 years. The highest participation was from Kütahya Province. According to the results of the tularemia microagglutination test, seropositivity was detected in 6 cases. It was determined that all of the seropositive volunteers were in Kütahya. When the tularemia antibody titers were examined, seropositivity was determined at 1/20-1/160 titers. No positivity was detected in the Rose-Bengal test for cross-reaction. DISCUSSION: Kütahya has been identified as a risky region in terms of tularemia in the Inner Aegean Region. In order to use the resources in the country economically, first of all, the risk areas in terms of tularemia should be determined by serological studies in all regions. In order to increase awareness about the disease, physicians and filiation teams should be trained in risky areas. Surveillance studies should be conducted to identify and monitor possible sources in areas identified as risky.

Genotyping and Identification of Antigen B Gene Polymorphism of Echinococcus granulosus in Edirne, Thrace, and the First Report of Genotype G2 (Tasmanian Sheep Strain) in Turkey

Background: Echinococcus granulosus is the causative agent of cystic echinococcosis in humans and livestock. It is common worldwide. Cystic echinococcosis is still an important public health problem in Turkey, which is an endemic region. Aims: To genotype Echinococcus granulosus isolates and investigate antigen B gene polymorphism in Thrace, Turkey. Study Design: A cross-sectional study. Methods: Seventy-five hydatid cyst materials obtained between June 2020 and May 2021 were included in the study. Hydatid cyst materials were collected from 12 humans from various hospitals in Edirne and 63 from slaughterhouse animals during the same period. Cyst materials were localized in 8 livers and 4 lungs in humans, 23 livers and 17 lungs in cattle, and 13 livers and 10 lungs in sheep. In the first step, the 12S ribosomal RNA gene was amplified by polymerase chain reaction for all samples and run on an agarose gel. Band patterns were used for strain typing. Then, the selected samples that represented each of the band patterns obtained by single-strand conformation polymorphism analysis were sequenced for AgB1, AgB2, mt-CO1, and mt-ND1 genes. Results: Three different genotypes in Edirne, Thrace, Turkey, were observed for Echinococcus granulosus: G1 (domestic sheep strain), G2 (Tasmanian sheep strain), and G3 (buffalo strain). G1 was the dominant genotype in Edirne, and G3 was the second most common. Additionally, polymorphism in AgB1 and AgB2 gene regions was found. Conclusion: This study is the first to report on Echinococcus granulosus G2 (Tasmania sheep strain) in Turkey and G3 (buffalo strain) and antigen B polymorphism in Thrace. The study results will contribute to the prevention and control programs for cystic echinococcosis in Turkey and worldwide.

Investigation of Antimicrobial Susceptibilities and Resistance Genes of Campylobacter Isolates from Patients in Edirne, Turkey.

Background: We aimed to determine the susceptibility of Campylobacter isolates obtained from patients to various antimicrobial agents and to investigate some related antimicrobial resistance genes. Methods: Fifty-six Campylobacter isolates obtained from fecal specimens by conventional methods at the Trakya University Health Center for Medical Research and Practice, Department of Medical Microbiology in Edirne, Turkey, from 2017-2017 were included. Antimicrobial susceptibilities were investigated by the gradient strip test method, and species determination was made by multiplex polymerase chain reaction (mPCR). The presence of the erm(B) gene and tet(O) gene was investigated in all isolates by PCR. DNA sequence analysis was performed to detect the presence of mutations in the 23S rRNA positions 2074 and 2075 in five isolates, including two erythromycin resistant isolates. The gyrA gene mutation was investigated by the mismatch amplification mutation assay (MAMA)-PCR. Results: In 54 C. jejuni isolates, resistance to erythromycin was 3.7%; to tetracycline, 59.3%; and to ciprofloxacin, 74.1%. Phenotypically, the tet(O) gene was detected in 33 tetracycline-resistant isolates, but no erm(B) gene was found in any of the Campylobacter isolates. As a result of the DNA sequencing, it was found no mutations in the 23S rRNA gene at the 2074 and 2075 positions. The gyrA mutation was observed in all 41 ciprofloxacin resistant Campylobacter isolates. Conclusion: Among the antimicrobial agents tested, ciprofloxacin had the highest resistance rate, and erythromycin had the lowest. Antimicrobial resistance in Campylobacter increased significantly compared with previously studies in our region as well as in the entire world. Monitoring the resistance to antimicrobial agents used to treat Campylobacter infections is important in determining empiric antimicrobial treatment.

Case of Prolonged Viral Shedding: Chronic, Intermittan COVID-19?

COVID-19 is a pandemic that has been affecting the entire world and has caused the death of approximately 2.8 million people. Although the duration of viral shedding varies, an average of 7-10 days is accepted. It is still unclear whether prolonged viral shedding means prolonged contagious period and whether COVID-19 will become chronic or not. This article presents a case with hematological malignancy (lymphoma) with the longest polymerase chain reaction positivity that we could find in the literature (110 days in total).

[A case of Infective Endocarditis Caused by Pseudoclavibacter species]. / Pseudoclavibacter spp.'nin Etken Oldugu Enfektif Endokardit Olgusu.

Infective endocarditis is an infectious disease usually caused by bacteria, including streptococci, staphylococci, and enterococci. In this report, a case of infective endocarditis in which Pseudoclavibacter spp. detected as the causative agent was presented. A 66-year-old female patient was admitted to our hospital with weight loss, malaise, and lumbar pain. A 2/6 murmur was detected in the physical examination of the patient, who had a history of mitral valve surgery nine years earlier. Blood sample was collected for culture and vancomycin [1 g/24 hours, intravenously (IV)] and gentamicin (80 mg/8 hours, IV) therapy were started. Gram-positive bacilli were detected on the second day of incubation in the blood culture bottle incubated in the BacT/ALERT 3D microbial detection system (bioMerieux, France). High uptake in the focal area of the mitral valve on positron emission tomography-computerized tomography (PET-CT) was interpreted as infective endocarditis. The patient was considered to be at very high risk for surgery and she was discharged after the vancomycin treatment completed for 42 days. For bacterial identification, DNA was isolated using a commercial kit (Invitrogen PureLink Genomic DNA Mini Kit; ThermoFisher Scientific, Waltham, MA, USA), and the 16S rRNA gene was amplified by a polymerase chain reaction (PCR) assay using universal primers 27F and 1492R. Sequence analysis of the PCR product was carried out on an Applied Biosystems 3730XL DNA Analyzer with an Applied Biosystems BigDye Terminator v3.1 Cycle Sequencing Kit (ThermoFisher Scientific, Waltham, MA, USA). A 1366 bp long sequence of the isolate was analyzed using the Basic Local Alignment Search Tool (BLAST) in GenBank and the sequence was 99% compatible with Gulosibacter spp. (GenBank sequence ID: LR884222.1, identity 1365/1366 bp) and Pseudoclavibacter spp. (GenBank sequence ID: FJ375951.1, identity 1364/1366 bp). Upon the negative result of nitrate reduction test of bacterium that was oxidasepositive, the bacterium was considered as Pseudoclavibacter spp. Linezolid, clindamycin, and tetracycline susceptibilities were determined by using the disc diffusion method. The isolate was susceptible to linezolid and resistant to clindamycin and tetracycline. It was also susceptible to penicillin [minimum inhibitory concentration (MIC) = 0.002 µg/ml], vancomycin (MIC= 0.25 µg/ml), and rifampicin (MIC= 0.003 µg/ml) and was categorized as "susceptible, increased exposure" to ciprofloxacin (MIC= 0.25 µg/ml), as determined by using a gradient strip test. Pseudoclavibacter species are non-spore-forming, non-motile, catalase-positive, aerobic gram-positive bacilli belonging to the Microbacteriaceae family. A limited number of clinical cases due to Pseudoclavibacter species have been reported. In the present case, gram-positive bacilli were considered to be the causative agent of infective endocarditis because of the growth of the same bacteria in six bottles of blood cultures taken at different times and increased focal involvement on PET-CT. To our knowledge, this is the second reported case of infective endocarditis due to Pseudoclavibacter species. In conclusion, in cases of clinical compliance in patients with prosthetic heart valves, gram-positive bacilli should be considered causative agents of infective endocarditis and in such cases, a range of microbiological assays should be used for identification.

Serological Follow-up of Human Cystic Echinococcosis in the Thrace Region, Turkey.

Background: Parasites of the genus Echinococcus are common worldwide and are important cestodes that cause serious infections in humans and animals. This retrospective study evaluated the indirect hemagglutination (IHA) test results of serum samples obtained from patients with a pre-diagnosis of cystic echinococcosis (CE) within ten years. In addition, the role of the IHA test results of the patients in the follow-up of the treatment and determining possible recurrences was investigated. Methods: The IHA test results of 2426 serum samples of patients with a pre-diagnosed CE admitted to Trakya University Health Center for Medical Research and Practice in Edirne, Turkey, between January 2011 and December 2020 were evaluated retrospectively. The data of 53 patients with CE who had medical treatment and/or postoperative follow-up serological records were evaluated. Results: Of 2426 IHA tests, 376 (15.5%) were seropositive, and 2050 (84.5%) were seronegative. It was determined that 376 serum samples detected as positive belonged to 207 patients with CE. Of 207 CE patients, 109 (52.7%) were female and 98 (47.3%) were male. The most common organ involvement was the liver in 186 (89.9%) cases. Of 53 patients, 16 were considered relapse cases. The median follow-up period for 16 recurrent cases was 31.8 (1-77) months. Our results showed a statistically significant correlation between long-term serological follow-up and recurrence detection (P=0.034). Conclusion: Long-term serological follow-up after treatment is considered useful in determining possible recurrent cases. CE is an important public health problem for endemic regions, including our country, and we think our study results will contribute to the status and follow-up of the disease.

[Effect of N-acetylcystein on Antibiofilm Efficiency of Antibiotics in Staphylococci Isolates]. / Stafilokok Izolatlarinda Antibiyotiklerin Antibiyofilm Etkinligi Üzerine N-asetilsisteinin Etkisi.

Biofilms are often responsible for the difficulties in the treatment of infectious diseases due to their properties that facilitate escape from antibiotic effect and their antiphagocytic effects. At least 65% of all infectious diseases are associated with biofilm-forming bacteria. As Staphylococcus aureus and Staphylococcus epidermidis are among the most common agents of hospital infections and the infections are mostly biofilm-related, they pose an important problem. In infectious isolates, the minimum biofilm eradication concentration (MBEK) values of biofilm forms are much higher than the minimum inhibition concentration (MIC) values of planktonic forms. This situation requires the use of much higher doses of antibiotics in the treatment of infections and causes an increase in antibiotic resistance. The N-acetylcysteine (NAC) molecule is known to be effective against biofilm by disrupting mature biofilms and reducing the adhesion of bacteria to surfaces. In this study, it was aimed to demonstrate i) the biofilm-forming abilities ii) the change in ampicillin and vancomycin MIC values in the presence of NAC molecules, iii) the change in the MBEK values of these antibiotics in the presence of NAC molecule and iv) the change in the expression levels of genes thought to be related to biofilm formation in the presence of the NAC molecule among S.aureus (n= 38) and S.epidermidis (n= 12) isolates isolated from various clinical specimens in Trakya University Health Research and Application Center. In this study, microplate crystal violet method was used to demonstrate the biofilm formation in staphylococci. Broth microdilution and checkerboard method were used to demonstrate the change in the presence of NAC molecule of the MIC and MBEC values of ampicillin and vancomycin. The effect of NAC on the expression of intercellular binding proteins A and D (icaA, icaD) and Staphylococcus regulatory protein A (sarA) genes, which are the genes involved in biofilm formation in staphylococci, was determined by quantitative real-time Polymerase Chain Reaction (qRt-PCR) method. The Student-t test was used to compare the control and experimental groups (concentrations detected with synergy and additive effect); p˂ 0.05 was accepted as the limit value of significance. In this study, when the NAC molecule was used together with ampicillin and vancomycin, it was determined that this combination lowers the MIC values of staphylococcus isolates and staphylococcal biofilm MBEK values; and also the expression levels of icaA, icaD and sarA which were effective in biofilm formation in staphylococci have not changed and decreased. As a result, in this study, it has been determined that the NAC molecule can be a new alternative for combined drug therapy and is promising in terms of bringing a new approach to treatment. In addition, it is thought that it is possible to use the NAC molecule together with different microorganisms and antimicrobial agents, and the results obtained in this study are considered to be guiding for further studies on this subject.

Investigation of antimicrobial resistance and virulence genes of Campylobacter isolates from patients in a tertiary hospital in Edirne, Turkey.

Purpose: Campylobacter is one of the most common pathogens that cause food-borne infections worldwide. The aim of this study was to determine the antimicrobial resistance rates and the presence of multiple virulence genes in Campylobacter isolates obtained from humans. Materials and Methods: In this study, 71 Campylobacter isolates obtained from human faecal samples were used. Antimicrobial susceptibility tests were performed through the gradient strip method. The presence of virulence genes was investigated by monoplex and multiplex polymerase chain reaction. Results: The rate of resistance of the 66 Campylobacter jejuni isolates was 12.1% for erythromycin, 40.9% for tetracycline and 68.2% for ciprofloxacin. Only one of five Campylobacter coli isolates was resistant to these three antimicrobial agents. The flaB, pldA, cdtA, cadF, cdtC and ceuE genes were found in all 66 of the C. jejuni isolates. In the C. jejuni isolates, positivity rates of 92.4% for flaA, 96.7% for cdtB, 98.5% for ciaB, 90.9% for dnaJ and 96.7% for racR were observed. The flaA, flaB, ciaB, cdtA and cdtC genes were present in all C. coli isolates. Conclusions: It was detected that there is an increase in antimicrobial resistance of Campylobacter strains in our region, and most of the isolates harbour virulence genes.

[A rarely isolated bacterium in microbiology laboratories: Streptococcus uberis]. / Mikrobiyoloji laboratuvarlarinda nadir izole edilen bir etken: Streptococcus uberis.

Streptococcus uberis is a gram-positive bacterium that is mostly responsible for mastitis in cattle. The bacterium rarely has been associated with human infections. Conventional phenotyphic methods can be inadequate for the identification of S.uberis; and in microbiology laboratories S.uberis is confused with the other streptococci and enterococci isolates. Recently, molecular methods are recommended for the accurate identification of S.uberis isolates. The aim of this report is to present a lower respiratory tract infection case caused by S.uberis and the microbiological methods for identification of this bacterium. A 66-year-old male patient with squamous cell lung cancer who received radiotherapy was admitted in our hospital for the control. According to the chest X-Ray, patient was hospitalized with the prediagnosis of ''cavitary tumor, pulmonary abscess''. In the first day of the hospitalization, blood and sputum cultures were drawn. Blood culture was negative, however, Candida albicans was isolated in the sputum culture and it was estimated to be due to oral lesions. After two weeks from the hospitalization, sputum sample was taken from the patient since he had abnormal respiratory sounds and cough complaint. In the Gram stained smear of the sputum there were abundant leucocytes and gram-positive cocci, and S.uberis was isolated in both 5% sheep blood and chocolate agar media. Bacterial identification and antibiotic susceptibility tests were performed by VITEK 2 (Biomerieux, France) and also, the bacterium was identified by matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) based VITEK MS system as S.uberis. The isolate was determined susceptible to ampicillin, erythromycin, clindamycin, levofloxacin, linezolid, penicillin, cefotaxime, ceftriaxone, tetracycline and vancomycin. 16S, 23S ribosomal RNA and 16S-23S intergenic spacer gene regions were amplified with specific primers and partial DNA sequence analysis of 16S rRNA polymerase chain reaction (PCR) products were performed by 3500xL Genetic Analyzer (Applied Biosystems, USA). According to the partial 16S rRNA gene sequencing results, bacterium was confirmed as S.uberis. This report makes a significant contribution to the number of case reports of human infections caused by S.uberis as the identification was performed by current microbiological methods in our case. In conclusion, S.uberis should be evaluated as an opportunistic pathogen among the immunosuppressed patients and in addition to phenotypic bacteriological methods, the other recent microbiological methods should also be utilized for the identification.

Molecular Characterization of Human and Animal Isolates of Echinococcus granulosus in the Thrace Region, Turkey.

OBJECTIVE: Echinococcus granulosus is the causative agent of cystic echinococcosis in humans and many domestic animals, and remains an important global health problem. The aim of this study was to genotype E. granulosus isolates obtained from humans and animals in the Thrace Region of Turkey. MATERIAL AND METHODS: A total of 58 isolates were obtained from patients who underwent surgery at several hospitals and from animals at a slaughterhouse in the province of Edirne. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of ribosomal internal transcribed spacer 1 fragments, and polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) of the partial mitochondrial NADH dehydrogenase subunit 1 (ND1) gene, was used to characterize human and animal E. granulosus isolates. To investigate the genetic characteristics of isolates, deoxyribonucleic acid (DNA) sequencing of the mitochondrial cytochrome c oxidase subunit 1 (CO1) and ND1 genes was performed. RESULTS: Fifty-eight E. granulosus isolates, including 42 from human, 13 from cattle and 3 from sheep were, analyzed. The results indicated two distinct genotypes: the G1 (sheep strain) and G7 (pig strain) genotypes. The sheep strain was shown to be the most common genotype of E. granulosus affecting humans, sheep and cattle. Among the concatenated partial CO1 and ND1 sequence data, eight haplotypes of Echinococcus species were identified in the present study. CONCLUSION: This is the first report indicating that the E. granulosus pig strain is present in humans in this region. We suggest that new strategies be designed for E. granulosus control programs in Turkey.

[Antifungal susceptibilities of Aspergillus spp. strains isolated from invasive aspergillosis cases]. / Invazif aspergillozlu olgulardan izole edilen Aspergillus spp. suslarinin antifungal duyarliliklari.

Aspergillus species found abundantly in the outer environment and hospital setting may lead to serious morbidity and mortality particularly in patients with suppressed immunity. This retrospective study was aimed to investigate the antifungal susceptibilities of Aspergillus spp. isolated from aspergillosis cases being hospitalized. Aspergillus spp. isolated from samples of the patients with suspected fungal infections between January of 2002 and October of 2007, were investigated. A total of 678 samples (420 lower respiratory tract, 202 sterile body fluids, and 56 biopsy/tissue specimens) from 569 patients were included in the study. The samples were incubated in 25 degrees C and 35 degrees C on brain-heart-infusion agar supplemented with blood and on Sabouraud dextrose agar. Gram and Giemsa stained samples were also examined by microscopy. Mold type of fungi were identified by conventional techniques. "Invasive aspergillosis" was described according to criteria of Invasive Fungal Infections Cooperative Group of the European Organization for Research and Treatment of Cancer. A. fumigatus (n = 8), A. flavus (n = 2) and A. niger (n = 2) were isolated from 12 patients' samples (2.1%), 9 of them were lower respiratory tract and one of each was ascid, brain biopsy and pleural fluid specimens. All of those patients have had an underlying diseases such as malignancy. The susceptibility of the isolates to caspofungin, voriconazole, itraconazole and amphotericin B was tested by broth microdilution susceptibility testing and to posaconazole by E-test (AB Biodisk, Sweden). The lowest minimum inhibitory concentration (MIC) (< or = 0.125 microg/ml) values were detected for caspofungin and posaconazole for Aspergillus spp., however, the highest MIC values were detected for amphotericin B (> 1 microg/ml). MIC values of the all strains except one, were detected as < or = 0.5 microg/ml for voriconazole and itraconazole. In one A. niger strain itraconazole MIC value was 2 microg/ml. Since the number of other species was low, MIC50 value was determined only for A. fumigatus strains and it was found that the highest MIC50 value was for amphotericin B (2 microg/ml) and the lowest MIC50 values were for posaconazole (0.064 microg/ml), caspofungin (0.064 microg/ml), itraconazol (0.25 microg/ml) and voriconazol (0.25 microg/ml). Since caspofungin and posaconazole revealed the lowest MIC values, they should be taken into consideration in choice of therapy of aspergillosis cases in our hospital.