[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.

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.

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.

[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.

Is there any relationship between streptococcal infection and multiple sclerosis?

BACKGROUND: Multiple sclerosis (MS) is an immune-mediated inflammatory demyelinating disease of uncertain etiology. Although the mechanisms of inducting autoimmunity by some of the infectious agents have been investigated, there is not yet enough research on streptococcal infections. MATERIAL/METHODS: To understand the effect of past group A streptococcal infection on MS, antistreptolysin O (ASO) and antideoxyribonuclease B (ADNase B) were measured in 21 patients with relapsing-remitting MS and 21 healthy blood donors by nephelometric assay. RESULTS: ADNase B levels in the patients with MS were found to be significantly higher than in the controls (p<0.001); however, ASO levels were similar in both groups. CONCLUSIONS: These findings indicate that a relationship between multiple sclerosis and streptococcal infections may exist, but to acquire a better understanding of the role of group A streptococci in the pathogenesis of multiple sclerosis, more studies with animal models are necessary.

Isolation ratio and T- serotyping of group A streptococci from pediatric upper respiratory tract infections in Turkey.

OBJECTIVE: Acute rheumatic fever can follow throat infections with group A streptococci. Certain serotypes of group A streptococci such as M1, M3, M5, M6, M14, M18, M19, M24 are associated with this disorder. Immunity to streptococci and to rheumatic fever depends on antibodies to the M proteins. Due to current scarcity of M-typing sera, many laboratories use T typing and opacity factor production for serotype identification of group A streptococci. In order to, investigate the most common serotypes of group A streptococci in our country in recent years we studied T-agglutination typing and opacity factor of 120 group A streptococci strains isolated from throat cultures of 930 children. METHODS: Diffuse, stable suspensions of group A streptococci were tested with polyvalent antisera (T,U,W,X,Y) by slide agglutination. Microplate method was used for opacity factor detection. RESULTS: T-protein -agglutination patterns U (2,4,6,28) were the most common among typeable strains. The rate of T-protein -agglutination patterns T (1,3,13, B3264) and X (8,14,25,Imp.19) were 20 % and 18 % respectively. Opacity factor production rate of isolated group A streptococci strains was 65%. CONCLUSION: To profit global assessment of rheumatic fever and rheumatic heart disease, more epidemiological and serotyping research is required in our country.