[Investigation of SARS-CoV-2-Specific Humoral and Cellular Immunity Values in Health Care Workers with COVID-19 Disease and Administered with COVID-19 Vaccine]. / COVID-19 Geçiren ve COVID-19 Asisi Olan Saglik Çalisanlarinda SARS-CoV-2'ye Özgü Humoral ve Hücresel Bagisiklik Degerlerinin Arastirilmasi.

For limiting the coronavirus disease-2019 (COVID-19) pandemic, the effects on both humoral and cellular immune responses due to vaccines and previous infection should be taken into consideration. In some of the studies about the humoral immune response of the virus and different vaccines, it has been suggested that there can be a discordance between cellular and humoral immune responses during COVID-19 infection. The aim of this study was to determine the effects of humoral and cellular immune responses against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antigens in three groups of healthcare workers (HCWs) who were vaccinated with two doses of inactivated virus vaccine (CoronaVac), non-vaccinated and recovered COVID-19 infection and non-infected healthy controls by comparing the variables of gender and age and to examine the relationships between them. In this study, the antibody recognizing the receptor binding domain (RBD) of the spike (S) glycoprotein (IgG-S), nucleocapsid protein (IgG-N) of SARS CoV-2 and Interferon Gamma (IFN-γ) titres were determined among non-infected and vaccinated with two doses of inactivated virus vaccine (IVV) (n= 56, 1st group: 27 men, 29 women), non-vaccinated and COVID-19 convalescents (CG) (n= 41; 2nd group: 21 men, 20 women) and non-vaccinated and non-infected healthy controls (HCG) (n= 23, 3rd group: 10 men, 13 women) in 120 HCWs. Diagnosis of all the participants in COVID-19 CG was confirmed for SARS CoV2 infection with reverse transcription polymerase chain reaction (RT-PCR) test according to manufacturer's instruction (Bio-speedy® SARS CoV-2 Double Gene RT-qPCR, Bioeksen R and D Technologies, Turkey). IgG-S and IgG-N antibody levels were determined quantitatively by Abbott Architect i2000 (Abbott Laboratories, Abbott Park, IL, USA) system. (Qiagen, MD, USA). IFN-γ levels were determined by using the QuantiFERON SARS-CoV-2 Starter Blood Collection Tubes (Qiagen, MD, USA). All statistical data analysis were conducted using SPSS (version 22, IBM Corp., Armonk, NY, USA). Student's independent t-test or Mann-Whitney U test was used for the differences between bivariate groups and Spearman Rank correlation was used to evaluate the monotonic relationship between nonnormally distributed data sets. Spearman rho > 0.7 denotes high, 0.7 > rho > 0.5 moderate and rho > 0.05 was considered as significant. For each of the immunity parameters, there were no significant differences between males and females in the IVV group, as well as in the CG. In neither of the groups age and immunity parameters were found to be highly correlated. All three immunity parameters of males in CG and IVV groups significantly differed from each other. Although humoral immunity parameters of females between CG and IVV groups did not show any significant difference, the IFN-γ titres significantly differed from each other. There were no significant differences in the IgG-S titres between CG and IVV combined gender groups. However, IgG-N and IFN-γ titres significantly differed from each other between CG and IVV groups. Antibody and particularly IFN-γ levels in two dose CoronaVac vaccinated group were less pronounced in comparison to the observed responses in COVID-19 convalescents group, indicating that CoronaVac may induce substantially less robust and persistent cellular and humoral responses than natural SARS-CoV-2 infection.

Clinical Accuracy of Instrument-Read SARS-CoV-2 Antigen Rapid Diagnostic Tests (Ag-IRRDTs).

This systematic review (PROSPERO registration number: CRD42021282476) aims to collect and analyse current evidence on real-world performance based on clinical accuracy of instrument-read rapid antigen diagnostic tests (Ag-IRRDTs) for SARS-CoV-2 identification. We used PRISMA Checklist and searched databases (PubMed, Web of Science Core Collection and FIND) for publications evaluating the accuracy of SARS-CoV-2 Ag-IRRDTs as of 30 September 2021, and included 40 independent clinical studies resulting in 48 Ag-IRRDT datasets with 137,770 samples. Across all datasets, pooled Ag-IRRDT sensitivity was 67.1% (95% CI: 65.9%-68.3%) and specificity was 99.4% with a tight CI. Pooled sensitivity and specificity of SARS-CoV-2 Ag-IRRDTs did not demonstrate a significant superiority over SARS-CoV-2 rapid antigen tests which do not require a reader instrument, even in the case where surveillance and screening datasets were excluded from the analysis. Nevertheless, they provide connectivity advantages and remove operator interface (in results-reading) issues. The lower sensitivity of certain brands of Ag-IRRDTs can be overcome in high prevalence areas with high frequency of testing. New SARS-CoV-2 variants are major concern for current and future diagnostic performance of these tests.

[The Second Shot of CoronaVac Vaccine May Cause Reduction of Antibody Levels in People who Previously had COVID-19]. / CoronaVac Asisinin Ikinci Dozu COVID-19 Geçirmis Kisilerde Antikor Düzeylerinin Düsmesine Neden Olabilir.

The CoronaVac vaccine is an inactivated type two-dose regimen vaccine developed and manufactured by Sinovac Life Sciences Company, in China. It has already been used in China's vaccination program, while 21 other countries (including Indonesia, Turkey and Brazil) also granted emergency use authorization for this vaccine. In Turkey, on January 14, 2021, healthcare workers (HCWs) started to be vaccinated with CoronaVac as the priority group in vaccination. An important question that arose at this time was about how the vaccination schedule would be for people who had previously had Coronavirus disease 2019 (COVID-19). The Centers for Disease Control and Prevention (CDC) recommends that those who have had a previous COVID-19 infection can be vaccinated regardless of their previous infection. CDC guidelines also mention that "…if antibody (Ab) testing was done after the first dose of an mRNA vaccine, the vaccination series should be completed regardless of the Ab test result". It should be noted here that this statement applies particularly to mRNA type vaccines, whereas CoronaVac jab is an inactivated type two-dose regimen vaccine. The aim of this study was to present interim results of our ongoing study to compare the effect of two doses of inactivated CoronaVac vaccine on humoral immunity of people who had previously severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, and those people who did not have the infection. In our study, CoronaVac jab containing 600 SU inactivated SARS-CoV-2 antigen was administered as 0.5 ml to 62 HCWs in Yeditepe University Hospital (Istanbul, Turkey), in accordance with the manufacturer's recommendations. Ab levels against spike receptor binding region of SARS-CoV-2 were measured quantitatively. SARS-CoV-2 IgG assay were performed using Abbott Architect i2000 instrument (Abbott Laboratories, Abbott Park, IL, USA). Ab titers were measured before vaccination (Ab0), one month after the first vaccination (Ab1), and one month after the second vaccination (Ab2). The Ab responses of 62 HCWs before and after CoronaVac vaccination were determined. Two groups were created. Group 1 consisted of 18 females and 15 males who were tested as COVID-19 positive, previously. Group 2 consisted of 20 females and 9 males who never had the infection. Minimum, median and maximum Ab0 values of Group1 were 1.6, 180.8 and 5582.6, respectively and Ab1 values were 26.3, 1005.7 and 3923.1; Ab2 values were 202.1, 1119.1 and 2885.9, (in au/mL) respectively. On the other hand, minimum, median and maximum Ab0 values of Group 2 were 0.1, 1.8, and 37.2, Ab1 values were 4.7, 72.7, 470.2, and Ab2 values were 270.3, 746.2 and 5554.1, respectively. In Group 1, 20 of the HCWs showed lower Ab2 titers, while 13 of the HCWs showed higher Ab2 titers than the Ab1 titers. Whereas in Group2 all HCWs had higher Ab2 titers than the Ab1 titers. When the increasing and decreasing Ab2 titers of both groups were evaluated with the 2×2 contingency table and Fisher's exact chi-square test, a statistically significant difference was found between the groups (p<0.001). As a result, we think that a single dose of CoronaVac vaccine similarly to mRNA vaccines can be administered to people who have had COVID-19 due to the possibility that the Ab levels measured after the first dose of vaccine will decrease after the second dose of vaccine.

[Evaluation of a Visually-Read Rapid Antigen Test Kit (SGA V-Chek) for Detection of SARS-CoV-2 Virus]. / SARS-CoV-2 Virüs Tespitinde Görsel Okunan Hizli Antijen Test Kitinin (SGA V-Chek) Degerlendirilmesi.

Although the reverse transcriptase polymerase chain reaction (RT-PCR) method has been accepted as the reference method in the detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA, it requires special laboratory conditions, complicated and expensive laboratory instruments, competent laboratory staff and long testing duration. Antigen testing methods such as enzyme immunoassay, fluorescent antibody and visually-read immunochromatographic rapid antigen detection (RAD) tests eliminated the above mentioned disadvantages of the RT-PCR. The aim of this study was to determine the performance of a RAD test kit (V-Chek, SGA Ltd, Ankara, Turkey). Two paired nasopharyngeal swabs were collected from each patient, and one of them was used for the RAD test, while the other one (different swab) was used to perform the RT-PCR test. SARS CoV-2 Double Gene RT-PCR kit (Bioeksen, Turkey) was used for RNA amplification on the Light Cycler 480 plate-based RT-PCR instrument (Roche, Switzerland). The SARS-CoV-2 double gene RT-PCR kit targeting the SARS-CoV-2 specific N (nucleocapsid) and Orf1ab gene regions was used for RNA amplification. The human RNaseP gene was used for nucleic acid extraction and inhibition control. The shape of the growth curves was examined and the non-sigmoidal curves were recorded as "negative". Sigmoidal curves with cycle threshold (Ct) <38 were evaluated as "positive". The Ct values of all positive results were recorded. V-Chek RAD test kit uses a colloidal gold enhanced double antibody sandwich type antigen test kit. A SARS-CoV-2 positive specimen produces a distinct color band in the test region, formed by the specific antibody-antigen colored conjugate complex. A positive or negative result is indicated by a colored line appearance on the test region. A colored line appears in the control region, independent of the SARS-CoV-2 presence. The result is visually read 10 minutes after the last drop of the sample liquid is dispensed into the sample well. Specificity and sensitivity values were calculated accepting the RT-PCR results as a standard. Agreement between two different techniques was assessed using Cohen's kappa score. 110 patients were enrolled in this study; 34 (30.9 %) of these patients had positive RT-PCR samples, with the mean of Ct values of 25.8 (95% CI= 24.1-27.5), median of Ct values of 26. In our study population, the overall sensitivity was 61.8% (95% CI= 45.4-78.1), and specificity was 100%. Taking RT-PCR as reference, Cohen's kappa score for the antigen test was 0.691. Fisher's exact test was p<0.001. In conclusion, the RAD kit used in the study determined to be useful for the rapid identification of COVID-19 patients. However, a negative result does not eliminate the possibility of COVID-19 infection and should be confirmed by RT-PCR and clinical findings.

Gemella morbillorum endocarditis in a patient with a bicuspid aortic valve.

Gemella morbillorum is one of the rare causative microorganisms of endocarditis. We herein report a case of infective endocarditis in a patient with bicuspid aortic valve caused by G. morbillorum. Infective endocarditis diagnosis was established based on the Modified Duke's criteria. The patient was successfully treated with medical-surgical management.

The gut microbiome in epilepsy.

The close relationship between epilepsy and autoimmune diseases and the fact that the cause of epilepsy is idiopathic in 60% of cases suggest that intestinal microbiota may play a role in the etiology of epilepsy. In this study, we analyzed and compared the intestinal microbiota composition of patients with idiopathic focal epilepsy (n = 30) and healthy volunteer group (n = 10) by 16s ribosomal DNA sequencing. Proteobacteria phylum was found to be higher in patients with epilepsy (25.4%) than in healthy volunteers group (1.5%). The genera of Campylobacter, Delftia, Haemophilus, Lautropia, Neisseria among Proteobacteria phylum were found to be statistically significantly higher in patients with epilepsy than in healthy volunteers (p < 0.05). Fusobacteria phylum was detected in 10.6% of the patients with epilepsy but not in the healthy volunteer group. The genus of the Fusobacteria phylum was found as Leptotrichia and Fusobacterium. In our study, taxonomic drift and significant differences in the intestinal microbiota of patients with epilepsy according to healthy volunteer group showed that autoimmune mechanisms and inflammation may have a role in the etiology of epilepsy. Our data should be supported by other studies as to the role of the intestinal microbiome in the prevention and treatment of epilepsy.

The Prevalence of Mixed Genotype Infections in Turkish Patients with Hepatitis C: a Multicentered Assessment.

BACKGROUND: HCV virus infections are one of the major health problems in the world that can cause cirrhosis and liver cancer at a higher rate than other hepatitis data. The aim of this study was to determine the prevalence of mixed infections with different HCV genotypes in Turkey and also to evaluate the current HCV genotype and sub-type distributions by a multicentered assessment. METHODS: The HCV genotype data of 17,578 hepatitis C patients collected from 23 centers from different geographic regions covering all Turkey were collected. The data included information about the HCV genotypes in the last 10 years (between 2007 and 2016), demographic properties of the patients and the methods/systems used to determine the genotypes. RESULTS: Two hundred twenty-eight of the patients (1.3%) had mixed genotype. The most common mixed genotype combination was 1b + 4 (0.83%) followed by 1a + 1b (0.26%). Genotype distribution varies according to geographical regions. However, genotype 1 (82.92%) was the most common genotype in all regions and all years. This was followed by genotype 3 (7.07%) and genotype 4 (5.43%). A variety of methods were used by the centers including sequencing, pyrosequencing, real-time PCR, in-house RFLP, reverse hybridization (LIPA), and hybridization. CONCLUSIONS: Infection with mixed HCV genotypes in Turkey is uncommon. Genotype distribution varies according to geographic regions; the most common genotype 1 is encountered all over the country, while genotypes 3 and 4 are only in some of the centers. Since there is limited information about mixed HCV infection, further investigations are needed to determine the clinical importance of mixed HCV infection.

Community-acquired Lower Urinary Tract Infections: Etiology, Antimicrobial Resistance, and Treatment Results in Female Patients.

BACKGROUND/PURPOSE: Most community-acquired urinary tract infections (UTIs) are usually treated empirically. The knowledge of antibiotic resistance patterns of the microorganisms causing UTI is essential for defining the empirical treatment. OBJECTIVE: The aim of the present study is to determine the distribution of bacterial strains isolated from lower UTIs and their resistance patterns against commonly used antimicrobial agents and treatment results in female patients. SUBJECTS AND METHODS: This is a retrospective analysis of medical case records of 90 female patients with lower UTI for a period of 4 years from January 2013 to December 2016 in a tertiary care hospital in the Trakya region of Turkey. RESULTS: The most common causative agent was Escherichia coli (66.6% of cases) followed by Klebsiella pneumoniae (16.6%). Fosfomycin was the most active agent against E. coli (resistant isolates: 5.5%), followed by nitrofurantoin (resistant isolates: 7.4%). Extended-spectrum beta-lactamases (ESBLs) production was observed in 29 (32.2%) isolates (22 in E. coli, 6 in K. pneumoniae, and 1 in Enterobacter spp.). The antimicrobial resistance rates among ESBL-producing E. coli isolates for trimethoprim-sulfamethoxazole, ciprofloxacin, fosfomycin, and nitrofurantoin were 77.7%, 72.7%, 13.6%, and 18.2%, respectively (P < 0.05). The estimated microbiological eradication rates for nitrofurantoin and fosfomycin were 89.7% and 83.8%, respectively. CONCLUSIONS: The results of the present study indicate that nitrofurantoin and fosfomycin may be considered for empirical therapy of lower UTIs in Trakya region of Turkey.

An unusual presentation of brucellosis: hepatic microabscesses.

Hepatic abscess due to Brucella species is an extremely rare complication especially in acute illness. Here, we report a case of hepatic microabscesses probably caused by Brucella in a 33-year-old woman with acute infection who was successfully treated with a combination of doxycycline and rifampicin for 3 months.

Streptococcus pneumoniae sepsis as the initial presentation of systemic lupus erythematosus.

OBJECTIVE: Infections are among the most important causes of morbidity and mortality in patients with systemic lupus erythematosus (SLE) but are rare initial presentation of the disease. Therefore, in this study, we describe a case of Streptococcus pneumoniae sepsis in a young woman with previously undiagnosed SLE. CASE REPORT: A 23-year-old female patient was admitted to our outpatient clinic complaining of high fever (40°C), chills, fatigue, generalized myalgia, and cough with brown sputum for 5 days. Blood cultures grew gram-positive coccus defined as S. pneumoniae using standard procedures. Antinuclear antibody was positive at a titer of 1/1,000, and anti-double-stranded DNA was positive at 984 IU/mL. She was diagnosed with SLE. Her respiratory symptoms and pleural effusion were considered to be due to pulmonary manifestation of SLE. CONCLUSION: The underlying immunosuppression caused by SLE could have predisposed the patient to invasive pneumococcal disease. It may also occur as a primary presenting feature, although a rare condition.

Antibacterial effects of curcumin: An in vitro minimum inhibitory concentration study.

AIM: To evaluate the antibacterial effect of curcumin with the minimum inhibitory concentration (MIC) method in standard bacterial strains. METHODS: The in vitro antibacterial activity of curcumin was evaluated against methicillin-sensitive Staphylococcus aureus (MSSA) (ATCC 29213), methicillin-resistant Staphylococcus aureus (MRSA) (ATCC 43300), Enterococcus faecalis (ATCC 29212), Bacillus subtilis (ATCC 6633), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922) and Klebsiella pneumoniae (ATCC 700603) using the macrodilution broth susceptibility test method. After incubation in tubes, the antibacterial activity of curcumin was detected by a lack of turbidity, which indicated the inhibition of bacterial growth. The concentration in the tube with the highest dilution showing no turbidity was defined as the MIC. RESULTS: The curcumin MIC values were 175 µg/ml, 129 µg/ml, 219 µg/ml, 217 µg/ml, 163 µg/ml, 293 µg/ml and 216 µg/ml against P. aeruginosa, B. subtilis, MSSA, MRSA, E. coli, E. faecalis and K. Pneumonia, respectively. CONCLUSION: This study revealed antibacterial effects of curcumin against standard bacterial strains in high concentrations. Animal experiments have demonstrated that curcumin applied at high doses has strong antibacterial activity. There is a need for further in vivo studies to shed light on antibacterial effects of curcumin with high concentrations.

[Can curcumin prevent the formation of Pseudomonas aeruginosa biofi lm on the surface of tympanostomy tubes?]. / Kurkumin, timpanostomi tüpleri yüzeyinde Pseudomonas aeruginosa biyofi lminin olusmasina engel olabilir mi?

Formation of bacterial biofilm on the surface of tympanostomy tubes are held responsible in the pathogenesis of post-tympanostomy tube otorrhea. To prevent the formation of biofilm, various methods were employed and varying degrees of success have been achieved. In some recent studies curcumin, which is the fenolic form of Curcuma longa (turmeric), has been pointed out to have inhibitory effects on virulence factors of Pseudomonas aeruginosa. The aim of this study was to investigate whether the administration of curcumin is able to prevent the formation of P.aeruginosa biofilm on the surface of silicone tympanostomy tubes in vitro conditions. For this purpose, qualitative and quantitative analysis of P.aeruginosa biofilm created on the surface of the tympanostomy tubes were performed following a period of 48 hours incubation in microplate wells that contained decreasing concentrations of curcumin. For qualitative analysis, specimens were evaluated with an environmental scanning electron microscope for the existence of biofilm. For the quantitative analysis, bacteria attached to the tube surface was detached using a combination of vortexing and sonication. Following serial dilutions, the obtained solution was then inoculated on the sheep blood agar plates using calibrated loop, incubated for 24 hours and the colony forming unit (CFU) per mL were recorded. Environmental scanning electron microscope analysis revealed that 100 µg/mL of curcumin could prevent formation of the biofilm. Lower concentrations of curcumin could not prevent the biofilm formation. Qualitative analysis also revealed that when the concentrations of curcumin in the wells were decreased, the number of CFU/mL was increased significantly. Mean number of CFU in 100 µg/mL and 12.5 µg/mL groups were 35±7.07 and 650±494, respectively. Curcumin could prevent formation of P.aeruginosa biofilm on the surface of tympanostomy tubes in vitro with concentrations lower than the MIC value. The results of the present study show that local administration of curcumin may prevent suppurative otitis media following tympanostomy tube insertion, keep the patency of the tube and decrease the rate of treatment failure. In vivo studies are needed to support the in vitro anti-biofilm action of curcumin on tympanostomy tubes.

Relationship among MIF, MCP-1, viral loads, and HBs Ag levels in chronic hepatitis B patients.

BACKGROUND/AIM: To determine whether macrophage migration inhibitory factor (MIF) and monocyte chemoattractant protein-1 (MCP-1) levels in patients with hepatitis B (HB) are different than in normal individuals and whether the HB surface antigen (HBs Ag) level and viral load are correlated with each other and with the two aforementioned parameters. MATERIALS AND METHODS: Sera were obtained from 52 chronic active HB (CAHB) patients and 33 healthy controls, and their MIF and MCP-1 levels were measured. Statistical analyses were performed. A value of P < 0.05 was considered statistically significant. RESULTS: The MIF and MCP-1 values of the control group were increased compared to those of the CAHB group. The MIF and MCP-1 levels were negatively correlated with HBs Ag levels and viral loads. The MIF and MCP-1 levels were positively correlated. The HBs Ag levels and the log10 of the viral loads were positively correlated. CONCLUSION: We conclude that the negative correlation of MIF and MCP-1 with viral load and HBs Ag levels may be due to T-cell deficiency, antinuclear antibody seropositivity, and/or inhibition of chemokine ligand 2 receptors by viral antigens. More studies with a greater number of subjects are needed to evaluate the potential role of MIF and MCP in CAHB.

[Epidemiology, clinical and microbiological characteristics of invasive streptococcal infections in Turkey, 2010-2011]. / Türkiye'de invazif streptokok enfeksiyonlarinin epidemiyolojisi, klinik ve mikrobiyolojik özellikleri, 2010-2011.

A one-year active surveillance study was conducted to investigate the epidemiological and microbiological characteristics of invasive group A streptococci (GAS) infections in Turkey and to provide data for the establishment of national preventive strategies related to invasive GAS infections. A total of 46 clinical microbiology laboratories from 12 different regions of Turkey (Istanbul; Eastern and Western Marmara; Eastern and Western Blacksea; Aegean; Mediterranean; Western, Central, Northeastern, Middle-eastern and Southeastern Anatolia) participated in the study. Accordingly, GAS strains isolated from sterile body sites (blood, cerebrospinal, synovial, pleural, peritoneal, pericardial fluids) in the study centers between June 2010-June 2011, were sent to Maltepe University Hospital Clinical Microbiology Laboratory for microbiological confirmation and further analysis. The isolates were identified by conventional methods, and for serotyping, opacity factor (OF) and T protein types were investigated. For genotyping GAS lysate preparation, emm gene amplification and sequencing were performed by using the protocols recommended by Centers for Disease Control and Prevention. A total of 65 invasive GAS strains were isolated in 15 of the participant centers, during the study period. The rate of invasive GAS isolation exhibited regional variation, with the highest rates in the Eastern Blacksea (Trabzon, n= 19), followed by Istanbul (n= 17) and Western Anatolia (Ankara, Konya, n= 14). Of the patients with invasive GAS infection 33 were female, 32 were male, with the age range of 0-89 years. GAS strains were most commonly isolated from soft tissue specimens (n= 18), followed by abscess material (n= 10), sterile body fluids (n= 8) and blood (n= 7) samples. Serotyping revealed that 55% (36/65) of the strains were OF positive, and the majority of T protein was polygroup T (n= 20), followed by U (n= 14), B (n= 5), X (n= 3) and Y (n= 2). T protein was not detected in 22 isolates. The strains were found to have 17 different emm types;emm1 (n= 13), emm4 (n= 6), emm6 (n= 6), emm12 (n= 6), emm24 (n= 4), emm14 (n= 3) and emm28 (n= 3). Nine of the strains could not be typed by sequencing. The correlation between emm typing and serotyping was detected as 58%. It was observed that 26-valent vaccines included 70.5% of the invasive GAS strains included in this study. Our study provided initial data concerning the epidemiological properties of invasive GAS infections and characterization of GAS strains in Turkey. The incidence of invasive GAS infections is low in our country. Although immunization programme by 26-valent GAS vaccine is not currently an urgent public health issue for our country, the results of this study indicated that emm types 4 and 24 should better be included in such a vaccine to be used in Turkey. Additionally, since epidemiological features of GAS infections and the microbiological characteristics of the strains can vary by time, for the diagnosis of invasive streptococcal infections and to take the necessary preventive measures, epidemiological studies should be conducted repeatedly.

[Blood culture positivity: is it pathogen or contaminant?]. / Kan Kültürü Pozitifligi: Etken ya da Kontaminasyon mu?

Blood culture is the gold standard for diagnosis of bloodstream infections. Many studies have shown that rapid isolation and identification of the microorganisms in blood culture and initiation of early antimicrobial therapy are critically important to reduce the mortality rate. It was found that the rate of contamination in blood cultures is increasing with automated systems developed to facilitate the growth of microorganism and tracking positivity. It is more difficult to interpret a positive blood culture result especially in the case of having only one sample bottle. In this study the effect of growth time observed in the automated blood culture systems was evaluated in terms of interpretation of blood culture results as being pathogens or contaminants. A total of 1201 blood cultures tested in BACTEC 9120 (Becton Dickinson, USA) system in Maltepe University Hospital Medical Microbiology Laboratory, Istanbul, Turkey during one-year period were included in the study and growth times were recorded for positive bottles. The decision about the growth as being a pathogen or contamination was made by considering the clinical condition of the patient, the number of positive blood cultures and the results of inflammation markers (white blood cell counts, procalsitonin and CRP levels). Of the blood cultures 290 (24%) yielded positive results and 73% (212/290) of them were evaluated as pathogens, while 27% (78/290) were identified as contaminants. The mean detection time for clinically significant isolates was 17.87 hours and for contaminants was 40.56 hours. The difference between the growth time of pathogens and contaminants was found statistically significant (p< 0.0001). With regard to all positive results, it was detected that 66% of the bacteria grew within the first 24 hours. While 29.6% of the pathogens grew within 12 hours, none of the contaminants grew during that time. The evaluation of growth time among staphylococci in terms of methicillin resistance revealed that methicillin- resistant staphylococci grew later (26 hours) than the susceptible ones (11 hours) both in the pathogen group and the contaminant group (p< 0.01). The data of our study emphasized that, the growth time detected in blood culture systems had a critical role in estimating whether the isolated microorganism is a pathogen or a contaminant, especially in case of lack of more than one blood samples. It was concluded that, the bacterial growth detected within the first 24 hours most probably indicated the microorganism as pathogen, while blood culture positivity detected after 48 hours strongly pointed out that it was contaminant. However, it should be considered that methicillin-resistant staphylococci needed much longer time than 24 hour for growth, both as pathogens or contaminants.

Primary lymphoepithelioma-like carcinoma of the lung: report of a rare case and review of the literature.

Primary lymphoepithelioma-like carcinoma of the lung is a rare type of non-small cell lung carcinoma. In this study, we aimed to present a 62-year-old smoker male with a primary lymphoepithelioma-like carcinoma of the hilar region of the left lung. The patient underwent left pneumonectomy and no adjuvant therapy was given. There were no other abnormalities on whole body PET/CT scan including the nasopharyngeal region. The patient showed seropositivity for EBV IgG but immunohistochemistry and PCR amplification studied on paraffin-embedded tissue sections of the tumor failed to show any sign of EBV infection within the tumor cells. He is alive and disease-free four months after the operation. Although primary lymphoepithelioma-like carcinoma of the lung is usually reported in young females with no history of tobacco use and the tumor cells are infected with EBV, it may rarely be seen in elderly males with a history of tobacco use and the tumor cells not infected with EBV.

[Serotypes and antimicrobial susceptibilities of invasive group A streptococci identified in eastern Black Sea region of Turkey]. / Türkiye'nin dogu karadeniz bölgesinden tanimlanmis invazif A grubu streptokoklarin serotipleri ve antimikrobiyal duyarliliklari.

Frequency of invasive group A streptococcus (GAS) infections is increasing worldwide in recent 20 years. Serotypes responsible for these clinical manifestations and their antibiotic susceptibilities should be known in order to establish preventive measures and initiate appropriate treatment. This study was aimed to determine the serotypes, antibiotic susceptibilities and inducible clindamycin resistance among invasive GAS isolated between 2006-2009 period. A total of 22 GAS strains isolated from clinical samples [sterile body fluids (peritoneal, pleural, pericardial, joint and cerebrospinal fluids), blood, tissue biopsy] of the patients (14 male, 8 female; age range: 3-82 years, median age: 59) who admitted to Karadeniz Technical University Faculty of Medicine, Farabi Hospital located in Trabzon province (Eastern Black Sea Region of Turkey), between March 2006 and March 2009 were included in the study. GAS serotypes were determined by the investigation of serum opacity factors (SOF), T proteins and M proteins. SOF production was investigated by microplate method using human serum and SOF types were determined by SOF-inhibition test using specific antisera. T protein types were detected by agglutination method using polyvalent anti-T sera, and M serotypes were detected by capillary precipitation method using M antisera. Antimicrobial susceptibility tests were performed by disk-diffusion method according to CLSI recommendations. SOF were positive in 9 (41%) samples. Use of T antiserum yielded T (n= 8) and U (n= 7) types and M antiserum M1 (n= 4) and M2 (n= 3) types. The overall antibiotic susceptibility rate of the isolates was 68% (15/22) and overall resistance rate was 32% (7/22). All of the GAS strains were found susceptible to benzylpenicillin, ceftriaxone, vancomycin, levofloxacine and linezolid, however 9 (41%) were intermediate susceptible to tetracycline and 1 (4.5%) was intermediate susceptible to erythromycin. Four (18%) strains were found resistant to tetracycline, while three strains (13.5%) were found resistant to chloramphenicol. Inducible clindamycin resistance was found positive only in one strain. The serotypes determined in this study indicated that 33% of our invasive serotypes were covered by the hexavalent vaccine and 62% by the 26-valent vaccine. Multi-center surveillance studies are required to determine the serotype distribution of invasive GAS in Turkey and to provide valuable information for the development of appropriate vaccines in our country.

[A frequently overlooked bacteria in clinical microbiology laboratories: Arcanobacterium haemolyticum]. / Klinik mikrobiyoloji laboratuvarinda siklikla atlanan bir etken: arcanobacterium haemolyticum.

Arcanobacterium haemolyticum, previously known as Corynebacterium haemolyticum, is a facultative anaerobic, gram-positive bacillus with negative catalase and positive CAMP inhibition test results. It may be the causative agent of about 0.5-3% of acute bacterial pharyngitis especially in children and young adults. Since growth of A.haemolyticum is usually inhibited by flora members and since it slowly develops hemolysis in sheep blood agar and its colony morphology resembles beta-hemolytic streptococci, it is frequently overlooked in the evaluation of throat cultures. The aims of this study were to investigate the isolation frequency of A.haemolyticum from the throat cultures of pediatric patients by using both sheep and human blood agar media, and to evaluate the performances of those media for the identification of A.haemolyticum. A total of 355 patients (median age: 7 years) who were admitted to pediatric outpatient clinics with the symptoms of tonsillopharyngitis between March-July 2010 period, were included in the study. Swab samples obtained from tonsils and posterior oropharynx were inoculated into a divided plate which contained 5% sheep blood agar in one half and 5% human blood agar in the other half. After incubation in 5% CO2 at 37°C, the beta-hemolytic colonies with a microscopic morphology of gram-positive bacilli were further evaluated on 24, 48 and 72th hours. Identification of A.haemolyticum was based on negative catalase test, positive reverse CAMP test and biochemical characteristics obtained by API-Coryne (bioMérieux, France) identification system. In our study, beta-hemolytic colonies were detected in the throat cultures of 56 (16%) patients, of which 14% (49/355) were identified as beta-hemolytic streptococci (46 group A, 2 group G, 1 group C), and 2% (7/355) were identified as A.haemolyticum. All of the A.haemolyticum isolates were characterized by the production of beta-hemolysis in human blood agar at 24 hours, while the beta-hemolysis generation time in sheep blood agar was 48 hours for four isolates and 72 hours for three isolates. A.haemolyticum was identified in 2% of children with tonsillopharyngitis during the five months study period in spring/summer. All of the strains were isolated at human blood agar in 24 hours. Thus, in order to isolate A.haemolyticum in routine throat cultures, sheep blood agar plates together with human blood agar plates should be used in clinical microbiology laboratories.

Effect of the pneumococcal conjugate vaccine on pneumococcal carriage in Turkish children.

BACKGROUND: The aim of our study was to evaluate the effect of the seven-valent pneumococcal conjugate vaccine which has recently been included in the national immunization schedule on the nasopharyngeal carriage of Streptococcus pneumoniae in a group of healthy Turkish children. This is the first study determining the efficacy of this vaccine in Turkey. METHODS: One hundred and thirty-eight children who had completed their pneumococcal vaccination series and 109 unvaccinated control subjects aged 12-59 months were included in the study between October 2007 and April 2008. A single nasopharyngeal swab sample was obtained from each subject. RESULTS: S. pneumoniae was isolated in 32 (12.9%) of 247 subjects. No significant differences were detected in pneumococcal carriage rate between the vaccinees and controls (10.1% vs 16.5%). Prevalence of vaccine type (VT) carriage was statistically lower in the vaccinated group than the controls while non-vaccine type carriage (NVT) was similar. Most frequently isolated vaccine serotype was 23F in the vaccinated group and 19F in the non-vaccinated group. Of the isolated S. pneumoniae, 13.3% were penicillin susceptible and 86.7% were non-susceptible. Vaccinees and controls did not differ statistically with respect to carriage rate of penicillin-resistant S. pneumoniae. All the pneumococcal isolates were susceptible to ceftriaxone, vancomycin, rifampicin and quinolones. CONCLUSION: Seven-valent conjugate vaccine induces long-term protection against carriage of VT S. pneumoniae in Turkish children. The ability of the conjugate vaccine to reduce transmission of antibiotic resistant S. pneumoniae may be possible if its introduction is coupled with a reduction in inappropriate use of antibiotics.