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Byline: S. Erensoy (1), A. A. SayA+-ner (2), S. Turkoglu (3), D. Canatan (4), U. S. Akarca (5), R. Sertoz (1), T. Ozacar (1), Y. Batur (5), S. Badur (3), A. Bilgic (1) Abstract: Background: TT virus (TTV) DNA has been found in a large proportion of patients with different forms of non-A-G hepatitis, however the clinical importance is unclear. We aimed to determine the genotypes of TTV isolates foung in blood donors and different patient groups from the western part of Turkey. Materials and Methods: TT DNA was investigated in serum samples of 91 volunteer blood donors (BD), 105 thalassemia (TH) patients, ten patients with fulminant hepatitis (FH) and 16 hemodialysis (HD) patients by heminested PCR using primers NG059, NG061 and NG063 from the ORF1 region. 39 isolates were genotyped by analyzing the partial sequence of ORF1. Results: TTV DNA was found in 75% of HD, 80% of FH, 61% of TH patients and in 51.6% of BD. Among the sequenced isolates, 14 (35.9%) belonged to genotype 1 (G1) and 25 (64.1%) belonged to genotype 2 (G2). Among the G2 sequences, 22 were grouped as G2c. Conclusion: TTV infection was common in the population studied, even with moderately sensitive primers. G2 was the major genotype of the studied population without any significant differences in distribution between various patient groups and BD. Author Affiliation: (1) Dept. of Microbiology and Clinical Microbiology, Medical Faculty, Ege University, Bornova, 35100 Izmir, Turkey. erensoy@med.ege.edu.tr, TR (2) Dept. of Microbiology and Clinical Microbiology, Medical Faculty, Dokuz Eylul University, Izmir, Turkey, TR (3) Dept. of Microbiology and Clinical Microbiology, Medical Faculty, Istanbul University, Turkey, TR (4) Suleyman Demirel University, Dept. of Pediatric Hematology, Isparta, Turkey, TR (5) Dept. of Gastroenterology, Medical Faculty, Ege University, Turkey, TR Article note: Received: December 27, 2001 * Revision accepted: April 4, 2002 S. Erensoy (corresponding author)

Objectives: This study aimed to analyze the antiretroviral drug resistance in antiretroviral treatment-naïve HIV-positive patients in the Aegean Region of Turkey from 2012 to 2019., Methods: The study included 814 plasma samples from treatment-naïve HIV-positive patients. Drug resistance analysis was performed by Sanger sequencing (SS) between 2012-2017 and by next-generation sequencing sequencing (NGS) between 2018-2019. SS was used to analyze resistance mutations in the protease (PR) and reverse transcriptase (RT) gene regions using a ViroSeq HIV-1 Genotyping System. PCR products were analyzed with an ABI3500 GeneticAnalyzer (Applied Biosystems). The sequencing of the HIV genome in the PR, RT, and integrase gene regions was carried out using MiSeq NGS technology. Drug resistance mutations and subtypes were interpreted using the Stanford University HIV-1 drug resistance database., Results: Transmitted drug resistance (TDR) mutation was detected in 34/814 (4.1 %) samples. Nonnucleoside reverse transcriptase inhibitor (NNRTI), nucleoside reverse transcriptase inhibitor (NRTI), and protease inhibitor (PI) mutations were identified in 1.4 % (n =12), 2.4 % (n =20), and 0.3 % (n = 3) of samples, respectively. The most common subtypes were B (53.1 %), A (10.9%), CRF29_BF (10.6%), and B + CRF02_AG (8,2%). The most common TDR mutations were E138A (3.4%), T215 revertants (1.7%), M41L (1.5%), and K103N (1.1%)., Conclusion: Transmitted drug resistance rate in the Aegean Region is compatible with national and regional data. Routine surveillance of resistance mutations may guide the safe and correct selection of initial drug combinations for antiretroviral therapy. The identification of HIV-1 subtypes and recombinant forms in Turkey may contribute to international molecular epidemiological data., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The increasing mutation frequency of the SARS-CoV-2 virus and the emergence of successive variants have made correct diagnosis hard to perform. Developing efficient and accurate methods to diagnose infected patients is crucial to effectively mitigate the pandemic. Here, we developed an electrochemical immunosensor based on SARS-CoV-2 antibody cocktail-conjugated magnetic nanoparticles for the sensitive and accurate detection of the SARS-CoV-2 virus and its variants in nasopharyngeal swabs. The application of the antibody cocktail was compared with commercially available anti-SARS-CoV-2 S1 (anti-S1) and anti-S2 monoclonal antibodies. After optimization and calibration, the limit of detection (LOD) determination demonstrated a LOD = 0.53-0.75 ng/mL for the antibody cocktail-based sensor compared with 0.93 ng/mL and 0.99 ng/mL for the platforms using anti-S1 and anti-S2, respectively. The platforms were tested with human nasopharyngeal swab samples pre-diagnosed with RT-PCR (10 negatives and 40 positive samples). The positive samples include the original, alpha, beta, and delta variants (n = 10, for each). The polyclonal antibody cocktail performed better than commercial anti-S1 and anti-S2 antibodies for all samples reaching 100% overall sensitivity, specificity, and accuracy. It also showed a wide range of variants detection compared to monoclonal antibody-based platforms. The present work proposes a versatile electrochemical biosensor for the indiscriminate detection of the different variants of SARS-CoV-2 using a polyclonal antibody cocktail. Such diagnostic tools allowing the detection of variants can be of great efficiency and economic value in the fight against the ever-changing SARS-CoV-2 virus., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Point of care (PoC) devices are highly demanding to control current pandemic, originated from severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2). Though nucleic acid-based methods such as RT-PCR are widely available, they require sample preparation and long processing time. PoC diagnostic devices provide relatively faster and stable results. However they require further investigation to provide high accuracy and be adaptable for the new variants. In this study, laser-scribed graphene (LSG) sensors are coupled with gold nanoparticles (AuNPs) as stable promising biosensing platforms. Angiotensin Converting Enzyme 2 (ACE2), an enzymatic receptor, is chosen to be the biorecognition unit due to its high binding affinity towards spike proteins as a key-lock model. The sensor was integrated to a homemade and portable potentistat device, wirelessly connected to a smartphone having a customized application for easy operation. LODs of 5.14 and 2.09 ng/mL was achieved for S1 and S2 protein in the linear range of 1.0-200 ng/mL, respectively. Clinical study has been conducted with nasopharyngeal swabs from 63 patients having alpha (B.1.1.7), beta (B.1.351), delta (B.1.617.2) variants, patients without mutation and negative patients. A machine learning model was developed with accuracy of 99.37% for the identification of the SARS-Cov-2 variants under 1 min. With the increasing need for rapid and improved disease diagnosis and monitoring, the PoC platform proved its potential for real time monitoring by providing accurate and fast variant identification without any expertise and pre sample preparation, which is exactly what societies need in this time of pandemic., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Published by Elsevier B.V.)

The construction of a rapid and easy immunofluorescence bioassay for SARS-CoV-2 detection is described. We report for the first time a novel one-pot synthetic approach for simultaneous photoinduced step-growth polymerization of pyrene (Py) and ring-opening polymerization of ε-caprolactone (PCL) to produce a graft fluorescent copolymer PPy-g-PCL that was conjugated to SARS-CoV-2-specific antibodies using EDC/NHS chemistry. The synthesis steps and conjugation products were fully characterized using standard spectral analysis. Next, the PPy-g-PCL was used for the construction of a dot-blot assay which was calibrated for applications to human nasopharyngeal samples. The analytical features of the proposed sensor showed a detection range of 6.03-8.7 LOG viral copy mL -1 (Ct Scores: 8-25), the limit of detection (LOD), and quantification (LOQ) of 1.84 and 6.16 LOG viral copy mL -1 , respectively. The repeatability and reproducibility of the platform had a coefficient of variation (CV) ranging between 1.2 and 5.9%. The fluorescence-based dot-blot assay was tested with human samples. Significant differences were observed between the fluorescence intensity of the negative and positive samples, with an overall correct response of 93.33%. The assay demonstrated a high correlation with RT-PCR data. This strategy opens new insights into simplified synthesis procedures of the reporter molecules and their high potential sensing and diagnosis applications., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Supply shortage for the development and production of preventive, therapeutic, and diagnosis tools during the COVID-19 pandemic is an important issue affecting the wealthy and poor nations alike. Antibodies and antigens are especially needed for the production of immunological-based testing tools such as point-of-care tests. Here, we propose a simple and quick magnetic nanoparticle (MNP)-based separation/isolation approach for the repurposing of infected human samples to produce specific antibodies and antigen cocktails. Initially, an antibody cocktail was purified from serums via precipitation and immunoaffinity chromatography. Purified antibodies were conjugated onto MNPs and used as an affinity matrix to separate antigens. The characterization process was performed by ELISA, SDS-PAGE, electrochemistry, isothermal titration calorimetry, and LC-Q-TOF-MS/MS analyses. The MNP-separated peptides can be used for mass spectrometry-based as well as paper-based lateral flow assay diagnostic. The exploitation of the current workflow for the development of efficient diagnostic tools, specific treatments, and fundamental research can significantly impact the present or eventual pandemic. This workflow can be considered as a two birds, one stone-like strategy., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)

Real-time reverse transcriptase-polymerase chain reaction (RT-PCR)-based assays are the gold standard for virus diagnosis. Point-of-care (POC) technologies have shown great progress during this period. Herein, we propose a novel fuchsine dye-loaded polymersome for a colorimetric paper-based dot blot spike protein diagnostic assay for COVID-19 via smartphone-assisted sensing. The prepared platform aimed to create an adaptable tool that competes with traditional nanoparticle-based assays employing gold and silver. Analytical characterization and application of the testing platform showed high sensitivity (10 times better than gold nanoparticles), stability, fast turnaround, and reproducibility. The potential and possibilities demonstrated by the current platform could be observed in its adaptability for different markers and pathologies. In addition, smartphone-assisted sensing emphasizes the ability to use the tool at home by common peoples which can lower the burden on the healthcare facilities and reach more underdeveloped regions., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The global pandemic of COVID-19 continues to be an important threat, especially with the fast transmission rate observed after the discovery of novel mutations. In this perspective, prompt diagnosis requires massive economical and human resources to mitigate the disease. The current study proposes a rational design of a colorimetric lateral flow immunoassay (LFA) based on the repurposing of human samples to produce COVID-19-specific antigens and antibodies in combination with a novel dye-loaded polymersome for naked-eye detection. A group of 121 human samples (61 serums and 60 nasal swabs) were obtained and analyzed by RT-PCR and ELISA. Pooled samples were used to purify antibodies using affinity chromatography, while antigens were purified via magnetic nanoparticles-based affinity. The purified proteins were confirmed for their specificity to COVID-19 via commercial LFA, ELISA, and electrochemical tests in addition to sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. Polymersomes were prepared using methoxy polyethylene glycol- b -polycaprolactone (mPEG- b -PCL) diblock copolymers and loaded with a Coomassie Blue dye. The polymersomes were then functionalized with the purified antibodies and applied for the preparation of two types of LFA (antigen test and antibody test). Overall, the proposed diagnostic tests demonstrated 93 and 92.2% sensitivity for antigen and antibody tests, respectively. The repeatability (92-94%) and reproducibility (96-98%) of the tests highlight the potential of the proposed LFA. The LFA test was also analyzed for stability, and after 4 weeks, 91-97% correct diagnosis was observed. The current LFA platform is a valuable assay that has great economical and analytical potential for widespread applications.

The global pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has revealed the urgent need for accurate, rapid, and affordable diagnostic tests for epidemic understanding and management by monitoring the population worldwide. Though current diagnostic methods including real-time polymerase chain reaction (RT-PCR) provide sensitive detection of SARS-CoV-2, they require relatively long processing time, equipped laboratory facilities, and highly skilled personnel. Laser-scribed graphene (LSG)-based biosensing platforms have gained enormous attention as miniaturized electrochemical systems, holding an enormous potential as point-of-care (POC) diagnostic tools. We describe here a miniaturized LSG-based electrochemical sensing scheme for coronavirus disease 2019 (COVID-19) diagnosis combined with three-dimensional (3D) gold nanostructures. This electrode was modified with the SARS-CoV-2 spike protein antibody following the proper surface modifications proved by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) characterizations as well as electrochemical techniques. The system was integrated into a handheld POC detection system operated using a custom smartphone application, providing a user-friendly diagnostic platform due to its ease of operation, accessibility, and systematic data management. The analytical features of the electrochemical immunoassay were evaluated using the standard solution of S-protein in the range of 5.0-500 ng/mL with a detection limit of 2.9 ng/mL. A clinical study was carried out on 23 patient blood serum samples with successful COVID-19 diagnosis, compared to the commercial RT-PCR, antibody blood test, and enzyme-linked immunosorbent assay (ELISA) IgG and IgA test results. Our test provides faster results compared to commercial diagnostic tools and offers a promising alternative solution for next-generation POC applications.

Our aim was to investigate the mutations in protease (PR), reverse transcriptase (RT), and integrase (IN) gene regions in human immunodeficiency virus (HIV) using a single amplicon via next-generation sequencing (NGS). The study included plasma samples from 49 HIV-1-positive patients, which were referred for HIV-1 drug resistance testing during 2017. A nested polymerase chain reaction (PCR) was performed after the RNA extraction and one-step reverse transcription stages. The sequencing of the HIV genome in the PR, RT, and IN gene regions was carried out using MiSeq NGS technology. Sanger sequencing (SS) was used to analyze resistance mutations in the PR and RT gene regions using a ViroSeq HIV-1 Genotyping System. PCR products were analyzed with an ABI3500 GeneticAnalyzer (Applied Biosystems). Resistance mutations detected with NGS at frequencies above 20% were identical to the SS results. Resistance to at least one antiretroviral (ARV) drug was 22.4% (11 of 49) with NGS and 10.2% (5 of 49) with SS. At least one low-frequency resistance mutation was detected in 18.3% (9 of 49) of the samples. Low-frequency resistance mutations resulted in virological failure in only one patient. The cost of the analyses was reduced by sample pooling and multiplex analysis using the MiSeq system. This is the first study in Turkey to use NGS technologies for the detection of resistance mutations in all three gene (PR, RT, IN) regions using a single amplicon. Our findings suggest that NGS is more sensitive and cost-effective than the SS method., (© 2020 Wiley Periodicals LLC.)

There have been a limited number of studies on coronavirus disease 2019 (COVID-19) in children. In this study, we aimed to investigate the demographic, clinical, and laboratory features of COVID-19 and to identify the role of mean platelet volume (MPV) in predicting the prognosis in children. A single-center retrospective study, including 251 confirmed and 65 suspected COVID-19 cases, was conducted between March 11, 2020, and December 11, 2020. In the confirmed COVID-19 group, 48 (19.1%) patients were asymptomatic, 183 (72.9%) mild, 16 (6.4%) moderate, 1 (0.4%) severe, and 3 were (1.2%) critically ill. Confirmed COVID-19 patients had significantly lower mean values of white blood cell (WBC), absolute neutrophil count, absolute lymphocyte count, platelet, and hemoglobin (p < .001). However, there was no significant difference in MPV levels between the two groups (p = .894). C-reactive protein (CRP), procalcitonin, fibrinogen, and NT-pro-BNP mean values were significantly lower in confirmed COVID-19 cases than suspected cases (p < .001). A total of 55 (21.9%) patients required hospitalization due to COVID-19, and MPV, WBC, CRP, procalcitonin, D-dimer, and NT-pro-BNP were statistically higher in hospitalized patients than those in outpatients. The multivariate analysis of confirmed COVID-19 cases according to the severity of disease showed that lymphopenia and higher levels of fibrinogen significantly associated with severe clinical symptoms. Decision tree analysis showed that the most powerful predictor of hospitalization due to COVID-19 was the D-dimer (p < .001). MPV values are not associated with COVID-19 disease severity. However, MPV can be used with other parameters such as WBC, CRP, procalcitonin, D-dimer, and NT-pro-BNP to predict hospitalization., (© 2021 Wiley Periodicals LLC.)

Objective: To evaluate the clinical features and outcomes of patients who were admitted with a diagnosis of coronavirus disease 2019 (COVID-19) but who were not confirmed with polymerase chain reaction (PCR) positivity., Material and Methods: This is a retrospective analysis of all patients admitted to two tertiary care centers between March 15 and May 15, 2020, with a diagnosis of COVID-19. From a common database prepared for COVID-19, we retrieved the relevant data and compared the clinical findings and outcomes of PCR-positive patients with those of PCR-negative cases who had been diagnosed on the basis of typical clinical and radiographic findings., Results: A total of 349 patients were included in the analysis, of which 126 (36.1%) were PCR-negative. PCR-negative patients were younger (54.6 ± 20.8 vs. 60.8 ± 18.9 years, P = .009) but were similar to PCR-positive patients in terms of demographics, comorbidities, and presenting symptoms. They had higher lymphocyte counts (1519 ± 868 vs. 1331 ± 737/mm3, P = .02) and less frequently presented with bilateral radiographic findings (68.3% vs. 79.4%, P = .046) than PCR-positive patients. Besides, they had less severe disease and better clinical outcomes regarding admission to the intensive care unit (9.6% vs. 20.6%, P = .023), oxygen therapy (21.4% vs. 43.5%, P < .001), ventilatory support (3.2% vs. 11.2%, P = .03) and length of hospital stay (5.0 ± 5.0 vs. 9.7 ± 5.9 days, P < .001)., Conclusion: This study confirms that about one-third of the COVID-19 patients are PCR-negative and diagnosed based on clinical and radiographic findings. These patients have a more favorable clinical course, shorter hospital stays, and are less frequently admitted to the intensive care unit.

Although a few studies have been done on transmissible blood-borne viral infections in high-risk groups, little attention has been given to assessing the infection status of the general population in Afghanistan. To investigate the epidemiological status in the general population, we tested the serological markers of hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis delta virus (HDV), human immunodeficiency virus 1 (HIV-1) and human T-cell leukemia virus (HTLV) infections. In total, 492 samples were selected randomly from Nangarhar, Herat, Mazar-e Sharif, Kandahar, and Kabul from subjects between 25 and 70 years old. The samples were tested for the presence of HBsAg, anti-HBs, anti-HBc, anti-HDV, anti-HCV, anti-HIV-1 and anti-HTLV I/II antibodies using chemiluminescent immunoassays on Abbott Architect automated platforms. In addition, 220 HBsAg-positive samples identified among 5897 samples from the general population of the same regions of Afghanistan were included in the study and tested for both HBsAg and anti-HDV to investigate HDV prevalence in the country. Viral loads of HBV, HCV and HDV were determined in all seropositive samples using Ampliprep/Cobas TaqMan HBV, HCV, Test Roche (CA, USA), and an in-house method, respectively. Out of 492 samples, 31 (6.3%), 136 (27.6%) and 149 (30.3%) were found to be positive for HBsAg, anti-HBs and anti-HBc, respectively. Anti-HDV positivity was detected in five (2.1%) out of 234 HBsAg-positive samples (including 14 of the randomly selected samples that were not among the 220 previously identified as HBsAg positive). Only eight out of 492 (1.6%) subjects were positive for anti-HCV antibodies. Seven out of 489 (1.4%) were positive for anti-HIV-1 antibodies, and three out of 466 cases (0.6%) were positive for anti-HTLV I/II antibodies. These results suggest that Afghanistan is an intermediate endemic region for HBV, HDV and HCV infection. The prevalence of HIV-1 seems to be significantly higher than the global prevalence and that of the eastern Mediterranean region. In addition, the HTLV I/II screening results suggest that these viruses should be monitored in Afghanistan to confirm the trend observed in the current study.

Objectives: Our objective was to evaluate the serologic positivity of cornea donors and microbiologic positivity of cornea storage media at the Ege University Tissue and Cornea Bank, Izmir, Turkey., Materials and Methods: We retrospectively investigated the serologic blood sample and microbiological culture media analysis results of all cornea donors at Ege University Tissue and Cornea Bank between 2007 and 2015 with reference to age, sex, and cause of death of each donor., Results: Mean age of the 955 deceased donors was 43.19 ± 15.89 years (range, 2-65 y). The mean postmortem time to blood sample removal and excision of the cornea tissue was 8.4 hours (range, 4-12 h). Serologic analyses showed that 855 donors (89.5%) were seronegative. The remaining donors were seropositive for hepatitis B (54 donors; 5.7%), human immunodeficiency (27 donors; 2.8%), hepatitis C (14 donors; 1.5%), and syphilis (5 donors; 0.5%) virus infections. Microbiologic analyses of the storage media were negative, with no microorganisms shown in 855 samples (89.5%). Candida species (32 donors; 3.4%), Escherichia coli (14 donors; 1.5%), Pseudomonas aeruginosa (11 donors; 1.2%), methicillin-resistant Staphylococcus aureus (11 donors; 1.2%), Enterobacter species (11 donors; 1.2%), Klebsiella pneumoniae (7 donors; 0.7%), Acinetobacter baumannii (6 donors; 0.6%), Proteus species (5 donors; 0.5%), and Corynebacterium species (3 donors; 0.3%) were the detected microorganisms in the infected storage media., Conclusions: False-positive serologic results among cornea donors were high. The incidence of false-positive results might be decreased by earlier blood removal from deceased donors and testing of all potential donors in intensive care units. Although rare, endophthalmitis after keratoplasty might be a devastating problem. In addition to serologic testing, microbiologic analyses of cornea storage media before transplant may be an effective way to prevent postoperative infectious complications.

Background/aims: Host-related immune factors in childhood chronic hepatitis B and change in the initial profile with interferon (IFN)-α treatment need to be clarified., Methods: Sixteen patients were included in the study, and 10 million units of IFN-α treatment 3 times per week for 6 months was initiated. Pre- and post-treatment percentages of interleukin (IL)-2 and IFN-γ in CD4+ T cells were assessed to determine intracellular T helper cell 1 (Th1) type cytokine expression. Similarly, percentages of intracellular IL-2 and IFN-γ were detected to verify cytotoxic T cell 1 (Tc1) type cytokine expression in CD8+ T cells. Percentages of Th2 and Tc2 type cytokine expression (IL-4 and IL-13) were determined in CD4+ and CD8+ T cells, respectively., Results: Six (50%) of these were evaluated as having no response and the other half with partial/complete response. All patients had higher percentages of Th2 cells with respect to healthy controls pre-treatment. Tc percentages, both Tc1 and Tc2, were significantly different between these groups, being higher in the patient group. When values of the nonresponder group were compared with healthy controls, IL-4 expression was higher and the percentages of Th1 type cells were significantly low. IL13 expression in Th and Tc cells decreased after 6 months of treatment in the unresponsive group. The decrease we observed in Th1 percentages with treatment, in the responsive group, may be due to Th1 deposition shifting from the periphery to liver tissue, as reported before. Intracellular cytokine profiles of treatment responders and normal controls were not different., Results: This is the first study in children comparing baseline and post-treatment intracellular cytokine profiles with values in healthy controls.

Background: In patients with chronic hepatitis B (CHB) infection, precise definition of the hepatic fibrosis stage is the most important parameter to assess the risk of disease progression. Correlation between the prognosis of the CHB and the level of hepatitis-B virus DNA (HBV-DNA) is well considered in recent years., Aims: The aim of this study is to investigate the relationship between serum HBV-DNA level and histology of the liver. We also wanted to determine a threshold level of HBV-DNA for differentiation of low and high risk patients for progression., Methods: Two-hundred-fifty-nine patients with serum HBV-DNA level > 2000 copies/mL, determined by polymerase chain reaction (PCR), and biopsy proven naïve CHB infection were evaluated. Liver biopsies were evaluated histopathologically according to the Ishak scoring system. Laboratory values such as aspartate aminotransferase (AST), alanine aminotransferase ratio (ALT) were tested every 3 months and the highest value of each patient was evaluated., Results: Mean age was 40 +/- 11 and 60% (155/259) of the patients were male. Mean laboratory values were as follows: AST: 52 +/- 46 U/L, ALT: 93 +/- 133 U/L, PLT: 224 +/- 60 1093)/l HBV DNA: 5.9 +/- 1.5 log copies/mL. In histological evaluation, mean inflammatory score was 4.34 +/- 2.72 and fibrosis score was 1.38 +/- 1.46. The fibrosis score was 0 or 1 in 63.3% (164/259) of the patients. The relationship between HBV-DNA level and histologic grade/stage was investigated and 15.000 copies/mL HBV DNA level was found as the threshold level to describe the activity of the disease. Fibrosis score was < 2 and/or grade < or = 5 in the patients who have HBV-DNA value below that level., Conclusion: In patients who have serum HBV-DNA level < or = 15000/copies/mL, histological activity was almost always low, and it seems that these patients do not need a liver biopsy regardless of hepatitis-B-e antigen (HBeAg) status.

A new multiplexed microparticle-based immunoassay was compared with the immunofluorescence assay that is used widely for detecting EBV-specific antibodies in immunocompetent patients. Serum samples of 162 patients submitted for routine EBV diagnosis were tested for viral capsid antigen IgM, viral capsid antigen IgG and serological profile interpretations with both systems. The result concordances were 94.2%, 93.6%, and 92.1%, respectively. Multiplexed microparticle-based immunoassay can be an alternative to immunofluorescence assay especially in laboratories receiving large numbers of samples.

The aim of this study was to compare direct sequence analysis of partial HBV pol gene and Inno-LiPA HBV DR in serum samples of 120 chronic hepatitis B patients sent to the Clinical Microbiology Laboratory of Ege University Hospital because of lamivudine resistance. Sequence analysis was performed on ABI Prism 310 Genetic Analyzer. Comparison of Inno-LiPA and sequence results obtained by double-blind evaluation showed full agreement (both at rt180 and rt204) in 58.8% of samples. Visually rechecking of the electropherograms increased this rate to 68.3% Codon based rates are 81.7% and 75.8% at rt180 and rt204 respectively. LiPA detected variants in additional 12 (10%) samples, but missed one variant sample (both rt180 and rt204) and one sample was indeterminate due to poor probe binding. LiPA allows determination of mixed variants and seems to be more sensitive and simple for routine testing even though sequence analysis is still the gold standard for detecting new variants.

We evaluated cord formation in MB/BacT broth as a rapid method for presumptive identification of the Mycobacterium tuberculosis complex. Kinyoun acid-fast-stained smears from 370 positive MB/BacT bottles were examined for the presence of serpentine cording. The smears were examined independently by two observers. Observer 1 (the supervisor of the mycobacteriology laboratory) examined all of the smears while observer 2 (a clinical microbiologist not familiar with acid-fast bacillus [AFB] microscopy) examined 148 randomly chosen smears that were read by observer 1 without knowledge of which smear was which. The sensitivity, specificity, and positive and negative predictive values of cording for the presumptive identification of M. tuberculosis read by observer 1 were 88.2, 97.4, 99.2, and 69.7%, respectively. These values were reported at 90.6, 52.3, 82.8, and 69. 7%, respectively, by observer 2. Our laboratory prevalence of M. tuberculosis among positive cultures was 78% during the time this study was conducted. At the time of positive signal of the MB/BacT bottles, the broth of the bottles had sufficient cell mass to allow for observation of the presence or absence of serpentine cording. The presence of cords in MB/BacT broth is a reliable criterion for rapid, predictive identification of the M. tuberculosis complex for laboratories with a high proportion of the M. tuberculosis complex when the smears are examined by a microbiologist who has experience with AFB staining.

The feasibility of using nucleic acid probes directly from positive MB/BacT broth to identify mycobacteria was determined in this study. A total number of 2,727 specimens were cultured into the MB/BacT (Organon Teknika) automated system and on conventional Loweinstein-Jensen (LJ) slants. The Gen-Probe AccuProbe culture identification tests (DNA probes) were used on samples from bottles which were identified as positive for mycobacteria by MB/BacT. Samples of positive MB/BacT broth (0.1 ml) were used directly in the broth culture method for the DNA probes as published by Gen-Probe. Centrifugation of the contents of the bottle was not done prior to probe testing. The number of mycobacteria detected by MB/BacT and LJ was 253 (221 isolates of M. tuberculosis and 32 isolates of mycobacteria other than M. tuberculosis [MOTT]). A total of 96.4% (213 of 221) of the bottles growing M. tuberculosis produced a positive direct DNA probe result for M. tuberculosis complex. One hundred percent (16 of 16) of the bottles growing M. gordonae produced a positive direct DNA probe result for M. gordonae. A total of 3.6% (8 of 221) of the bottles growing M. tuberculosis did not yield a positive direct DNA probe result for M. tuberculosis complex. The testing of subcultures made onto solid media from the positive bottles by AccuProbe identified six of these eight M. tuberculosis isolates. Two (0.9%) M. tuberculosis isolates gave a negative result for the M. tuberculosis probe test applied on the MB/BacT broth and its subculture. The rest of the positive MB/BacT bottles growing MOTT (16 of 32) were negative for M. gordonae, M. avium, M. intracellulare, and M. kansasii probes. The sensitivity and specificity of AccuProbe for the identification of M. tuberculosis and M. gordonae directly from MB/BacT broth were 96.4 and 100% for M. tuberculosis and 100 and 100% for M. gordonae, respectively. The direct testing of positive MB/BacT broth by AccuProbe, without prior centrifugation, allows for the accurate and rapid identification of M. tuberculosis and M. gordonae.