Gonorrheal and chlamydia yield for genital and extragenital testing in children evaluated for sexual abuse.

OBJECTIVE: Texas Forensic Nurse Examiners (TXFNE) performs routine testing of genital and non-genital sites for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG), and further testing for other sexually transmitted pathogens. The current Centers for Disease Control and Prevention (CDC) guidelines recommend that testing be based primarily on patient history of type of sexual contact, patient age, community prevalence of sexually transmitted infections (STIs), perpetrator risk factors for STIs, and patient symptoms (Centers for Disease Control and Prevention, 2021). In this study, we were interested in determining whether our practice of testing all sites in all prepubertal patients presenting for sexual abuse for CT and NG resulted in identification of infections that would have been missed if testing had been limited to disclosed sites of sexual contact. METHODS: We conducted a retrospective chart review of all children younger than 14 years who presented to a clinical or hospital site for evaluation by TXFNE in Harris County or surrounding counties during the period January 2020-December 2021. RESULTS: Of the 675 patients tested, 61 patients (9 %) had genital injuries and 45 patients (7 %) had either reported symptoms or examination findings consistent with possible STI infection. There were 11 patients who had positive gonorrhea and/or chlamydia results. Of the 11 patients with a positive result, 10 patients' reported history of type of contact did not fully match sites that tested positive. Diagnosis of STI infection would have been missed for 5 patients if testing had been limited to the disclosed sites of sexual contact. CONCLUSION: Positive results for CT and NG at undisclosed body sites in children presenting with concern for sexual abuse most likely represent infection from sexual contact. Limiting STI testing based on disclosed contact may lead to missed NG and CT infections in prepubertal patients with concern for sexual abuse. This can lead to delayed treatment of the infection and a missed opportunity to ensure the safety of the child.

Detection of Trichomonas vaginalis by Allplex™ STI Essential Assay (Seegene) in clinical samples from the Brazilian public health system users.

The failures in Trichomonas vaginalis (TV) infection diagnosis leave more than half of cases unidentified. In this report, urine and vaginal discharge samples were analyzed by wet mount, culture examination, and real-time PCR by Allplex™ (Seegene®) kit, in a population assisted by the Brazilian Public Health System. From 747 samples, 2.81% were positive for TV in wet mount and culture, and 3.88% by Allplex™. Samples kept at - 80 ºC for 22 months did not impair the PCR technique. The sensitivity for wet mount, culture, and Allplex™ was 72, 100, and 100%, respectively. Allplex™ technique showed highest detection of TV.

Correlation of serological and molecular markers in the screening for hepatitis B virus in blood bank in northern Brazil

ABSTRACT Introduction: In Brazil, the blood donor screening for hepatitis B virus (HBV) includes laboratory testing for serological (HBsAg and Anti-HBc) and molecular (HBV DNA) markers. This study aims to correlate serology reactive results with HBV DNA detection among blood donors with at least one HBV infection marker detected in a blood bank in northern Brazil. Method: A retrospective search for HBV reactive blood donor data from January 2017 to December 2019 was performed. Serological screening was performed by chemiluminescent microparticle immunoassays Architect HBsAg and Architect Anti-HBc, whereas molecular screening was performed by the HBV nucleic acid test (HBV NAT). Main results: A total of 556 HBsAg reactive results were detected, between positive (47.66%) and inconclusive (52.34%). A total of 3,658 Anti-HBc reactive results were detected, between positive (83.71%) and inconclusive (16.29%). None of the inconclusive results were associated with HBV DNA detection. The HBV DNA detection rates were 47.55% among HBsAg positive samples and 4.08% among Anti-HBc positive samples. The signal-to-cutoff (S/CO) ratio median of HBV NAT positive samples was superior in comparison to HBV NAT negative samples (p < 0.0001). The thresholds found to optimize sensitivity and specificity were 404.15 for Architect HBsAg and 7.77 for Architect Anti-HBc. Three blood donors were in the window period and 1 occult HBV infection case was detected. Conclusion: High S/CO ratios were more predictive of HBV DNA detection. However, a number of HBV NAT positive samples gave low values, while some HBV NAT negative samples showed high values, reaffirming the significance of molecular testing to enhance transfusion safety.

Impact of time of culture specimen collection on the recovery of Neisseria gonorrhoeae after a positive nucleic acid amplification test.

OBJECTIVES: Culture of Neisseria gonorrhoeae remains essential for antimicrobial resistance (AMR) surveillance. We evaluated the effect of time of specimen collection on culture yield following a positive nucleic acid amplification test (NAAT). METHODS: We retrospectively assessed N. gonorrhoeae culture yield among asymptomatic individuals (largely men who have sex with men) who attended for sexual health screening and had a positive NAAT. Participants underwent either same-day testing and notification (Drassanes Exprés) or standard screening with deferred testing. RESULTS: Among 10 423 screened individuals, 809 (7.7%) tested positive for N. gonorrhoeae. A total of 995 different anatomical sites of infection culture was performed in 583 of 995 (58.6%) of anatomical sites (Drassanes Exprés 278 of 347, 80.1%; standard screening 305 of 648, 47.1%; p<0.001). Recovery was highest when culture specimens were collected within 3-7 days of screening with only a slight drop in recovery when the interval extended to 7 days . Recovery from pharynx was 38 of 149 (25.5%) within 3 days, 19 of 81 (23.4%) after 4-7 days (p=0.7245), 11 of 102 (10.7%) after 8-14 days (p<0.0036) and 1 of 22 (4.5%) with longer delays (p=0.00287). Recovery from rectum was 49 of 75 (65.3%) within 3 days, 28 of 45 (62.2%) after 4-7 days (p=0.7318), 41 of 69 (59.4%) after 8-14 days (p=0.4651) and 6 of 18 (33.3%) with longer delays (p=0.0131). Median culture specimen collection time was 1 day within Drassanes Exprés vs 8 days within standard screening. Consequently, the overall culture yield was slightly higher within Drassanes Exprés (102/278, 36.6% vs 99/305, 32.5%; p=0.2934). CONCLUSION: Reducing the interval between screening and collection of culture specimens increased N. gonorrhoeae recovery in extragenital samples. Implementing a same-day testing and notification programme increased collection of culture samples and culture yield in our setting, which may help AMR surveillance.

Establishment of Ph. Eur. Hepatitis C Virus RNA for NAT testing BRP batch 2.

The European Pharmacopoeia (Ph. Eur.) monographs Human plasma for fractionation (0853) and Human plasma (pooled and treated for virus inactivation) (1646) require that plasma pools be tested for hepatitis C virus (HCV) RNA presence by nucleic acid amplification techniques (NAT) using a positive control at 100 IU/mL. HCV RNA for NAT testing BRP batch 1 was established in 1999 to this end. Due to dwindling stocks, the European Directorate for the Quality of Medicines & HealthCare (EDQM) organised a collaborative study to establish a replacement batch. The candidate material was produced as a lyophilised preparation of human plasma containing HCV genotype IA and calibrated against the 6th WHO International Standard for HCV RNA for NAT. Quantitative and qualitative HCV NAT assays based on real-time quantitative PCR techniques were used. Both types of assays were assessed separately. However, since no significant difference was observed between them, all results were pooled for the final potency assignment. Calculations based on Ct values were less variable than those based on end-point dilutions; they were thus used in the final combination. The combined overall mean potency was 959 IU/vial. An accelerated degradation study showed that the stability of the candidate material was satisfactory at the recommended long-term storage temperature, i.e. -20°C. The candidate BRP was established as Ph. Eur. HCV RNA for NAT testing BRP batch 2 by the Ph. Eur. Commission, with an assigned potency of 960 IU/vial. It will be available from the EDQM under catalogue number H0215000.

PivNG primers and probes set used in the cobas omni Utility Channel is a reliable supplemental test for detection of Neisseria gonorrhoeae in oropharyngeal, urogenital and rectal specimens collected in cobas PCR Media.

OBJECTIVE: To evaluate the clinical performance of the novel PivNG primers and probes set (PivNG test) used in the cobas omni Utility Channel for supplemental testing of Neisseria gonorrhoeae (NG). METHODS: Oropharyngeal, urogenital and rectal samples were self-collected during routine testing at Barts Health sexual health clinics, London, UK. Samples were tested by the cobas CT/NG test and PivNG cobas omni Utility Channel test on cobas 6800/8800 Systems. Supplemental testing was carried out with the Xpert CT/NG test. PivNG overall percent agreements, positive percent agreements (PPAs)/negative percent agreements (NPAs) and positive/negative predictive values were calculated for each sample type. Microscopy and/or culture data were included for a randomised subset of concordant/discordant results, and a composite reference standard (cobas CT/NG, Xpert CT/NG and culture results) adjusted for partial verification bias was used to determine PivNG PPA and NPA. RESULTS: Of 447 evaluable samples with valid results from all three assays (cobas CT/NG, PivNG and Xpert CT/NG), 288 (64.4%) were NG-positive by both PivNG and cobas CT/NG; 117 (26.2%) were NG-negative in both tests; and 42 (9.4%) had discordant results (with NG-negative supplementary Xpert) CT/NG results in 40/42 instances). Of 19 PivNG/Xpert CT/NG-discordant samples, 11 were confirmed NG-positive by microscopy and/or culture results. PivNG PPA and NPA were 100% and 91% for oropharyngeal swabs, 100% and 100% for vaginal swabs, 100% and 100% for male urine samples, and 100% and 97% for rectal swabs, respectively, compared with the partially adjusted composite reference standard. CONCLUSIONS: PivNG is a reliable supplementary test with high sensitivity for confirming NG infection when used in conjunction with the cobas CT/NG test and samples collected in cobas PCR Media. Moreover, the PivNG test offers a convenient, high-throughput solution for supplemental NG testing of various sample types, with the potential to reduce the number of indeterminate reports.

Next-generation molecular diagnostics: Leveraging digital technologies to enhance multiplexing in real-time PCR.

Real-time polymerase chain reaction (qPCR) enables accurate detection and quantification of nucleic acids and has become a fundamental tool in biological sciences, bioengineering and medicine. By combining multiple primer sets in one reaction, it is possible to detect several DNA or RNA targets simultaneously, a process called multiplex PCR (mPCR) which is key to attaining optimal throughput, cost-effectiveness and efficiency in molecular diagnostics, particularly in infectious diseases. Multiple solutions have been devised to increase multiplexing in qPCR, including single-well techniques, using target-specific fluorescent oligonucleotide probes, and spatial multiplexing, where segregation of the sample enables parallel amplification of multiple targets. However, these solutions are mostly limited to three or four targets, or highly sophisticated and expensive instrumentation. There is a need for innovations that will push forward the multiplexing field in qPCR, enabling for a next generation of diagnostic tools which could accommodate high throughput in an affordable manner. To this end, the use of machine learning (ML) algorithms (data-driven solutions) has recently emerged to leverage information contained in amplification and melting curves (AC and MC, respectively) - two of the most standard bio-signals emitted during qPCR - for accurate classification of multiple nucleic acid targets in a single reaction. Therefore, this review aims to demonstrate and illustrate that data-driven solutions can be successfully coupled with state-of-the-art and common qPCR platforms using a variety of amplification chemistries to enhance multiplexing in qPCR. Further, because both ACs and MCs can be predicted from sequence data using thermodynamic databases, it has also become possible to use computer simulation to rationalize and optimize the design of mPCR assays where target detection is supported by data-driven technologies. Thus, this review also discusses recent work converging towards the development of an end-to-end framework where knowledge-based and data-driven software solutions are integrated to streamline assay design, and increase the accuracy of target detection and quantification in the multiplex setting. We envision that concerted efforts by academic and industry scientists will help advance these technologies, to a point where they become mature and robust enough to bring about major improvements in the detection of nucleic acids across many fields.

Stimulus-Responsive DNA Hydrogel Biosensors for Food Safety Detection.

Food safety has always been a major global challenge to human health and the effective detection of harmful substances in food can reduce the risk to human health. However, the food industry has been plagued by a lack of effective and sensitive safety monitoring methods due to the tension between the cost and effectiveness of monitoring. DNA-based hydrogels combine the advantages of biocompatibility, programmability, the molecular recognition of DNA molecules, and the hydrophilicity of hydrogels, making them a hotspot in the research field of new nanomaterials. The stimulus response property greatly broadens the function and application range of DNA hydrogel. In recent years, DNA hydrogels based on stimulus-responsive mechanisms have been widely applied in the field of biosensing for the detection of a variety of target substances, including various food contaminants. In this review, we describe the recent advances in the preparation of stimuli-responsive DNA hydrogels, highlighting the progress of its application in food safety detection. Finally, we also discuss the challenges and future application of stimulus-responsive DNA hydrogels.

Environmental contamination by Chlamydia trachomatis and Neisseria gonorrhoeae: is it time to change our infection control practices? Results of a regional study.

OBJECTIVES: Nucleic acid amplification tests (NAATs) are highly sensitive for the detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) DNA/ribosomal RNA (rRNA). Previous studies have demonstrated contamination of surfaces in sexual health clinics (SHCs) with CT/NG. False positive results can occur if patient samples are contaminated by environmental DNA/rRNA. This can have a dramatic impact on patients' lives and relationships. Previous attempts to reduce contamination, through staff training alone, have been unsuccessful. We aimed to investigate environmental contamination levels in SHCs and to assess a two-armed intervention aimed at reducing surface contamination. METHODS: Questionnaires were sent to 10 SHCs. Six clinics, with differing characteristics, were selected to participate in sample collection. Each clinic followed standardised instructions to sample surfaces using a CT/NG NAAT swab. Clinics were invited to introduce the two-armed intervention. The first arm was cleaning with a chlorine-based cleaning solution once daily. The second arm involved introducing clinic-specific changes to reduce contamination. RESULTS: 7/10 (70%) clinics completed the questionnaire. Overall, 88/263 (33%) swabs were positive for CT/NG. Clinics 1, 3 and 4 had high levels of contamination, with 28/64 (44%), 17/33 (52%) and 30/52 (58%) swabs testing positive, respectively. Clinics 2 and 6 had lower levels of contamination, with 7/46 (15%) and 6/35 (17%), respectively. 0/33 (0%) of swabs were positive at clinic 5 and this was the only clinic already using a chlorine-based solution to clean all surfaces and delivering twice-yearly clinic-specific infection control training. Following both intervention arms at clinic 1, 2/50 (4%, p<0.0001) swabs tested positive for CT/NG. Clinic 4 introduced each arm separately. After the first intervention, 13/52 (25%, p=0.003) swabs tested positive and following the second arm 4/50 (8%, p<0.0001) swabs were positive. CONCLUSIONS: Environmental contamination is a concern in SHCs. We recommend that all SHCs monitor contamination levels and, if necessary, consider using chlorine-based cleaning products and introduce clinic-specific changes to address environmental contamination.

Second hepatitis C virus transmission by blood components since introduction of mandatory NAT screening in Germany.

BACKGROUND: Viral safety of blood products in Germany has improved significantly over the last two decades. We describe the second documented transfusion-transmitted (TT) episode for the hepatitis C virus (HCV) in Germany since mandatory nucleic acid amplification techniques (NAT) screening was introduced in 1999. STUDY DESIGN AND METHODS: When a repeat donor who had tested negative for anti-HCV tested positive for HCV RNA by NAT in a minipool (MP) of eight, a look-back procedure was initiated. Qualitative, quantitative and genotyping assays were used to investigate the titers of the quarantined fresh frozen plasma (FFP) from the donor and a serum sample from the recipient of the pooled platelet concentrate (PPC). Amplified products of 5'UTR and HVR1 were used for sequence comparison to characterize the HCV genomic identity of donor and recipient samples. RESULTS: All NAT tests utilized in this procedure were able to detect a low HCV RNA titer (~15 IU/ml) in the FFP from the donation. Dilution of FFP by factor 8 was performed to mimic an MP, and the detection rate correlated well with the claimed sensitivity of the tests. Analysis of donor and recipient samples revealed genotype 3a viral transmission confirmed by sequence analysis. CONCLUSION: This TT HCV case could have been prevented by individual donation (ID) NAT. However, a low titer blood donation in the window period (WP) is very rare. Residual risk calculation for TT HCV in the WP revealed that, compared to MP-NAT testing, ID-NAT would improve blood safety only marginally.

Correlation of serological and molecular markers in the screening for hepatitis B virus in blood bank in northern Brazil.

INTRODUCTION: In Brazil, the blood donor screening for hepatitis B virus (HBV) includes laboratory testing for serological (HBsAg and Anti-HBc) and molecular (HBV DNA) markers. This study aims to correlate serology reactive results with HBV DNA detection among blood donors with at least one HBV infection marker detected in a blood bank in northern Brazil. METHOD: A retrospective search for HBV reactive blood donor data from January 2017 to December 2019 was performed. Serological screening was performed by chemiluminescent microparticle immunoassays Architect HBsAg and Architect Anti-HBc, whereas molecular screening was performed by the HBV nucleic acid test (HBV NAT). MAIN RESULTS: A total of 556 HBsAg reactive results were detected, between positive (47.66%) and inconclusive (52.34%). A total of 3,658 Anti-HBc reactive results were detected, between positive (83.71%) and inconclusive (16.29%). None of the inconclusive results were associated with HBV DNA detection. The HBV DNA detection rates were 47.55% among HBsAg positive samples and 4.08% among Anti-HBc positive samples. The signal-to-cutoff (S/CO) ratio median of HBV NAT positive samples was superior in comparison to HBV NAT negative samples (p < 0.0001). The thresholds found to optimize sensitivity and specificity were 404.15 for Architect HBsAg and 7.77 for Architect Anti-HBc. Three blood donors were in the window period and 1 occult HBV infection case was detected. CONCLUSION: High S/CO ratios were more predictive of HBV DNA detection. However, a number of HBV NAT positive samples gave low values, while some HBV NAT negative samples showed high values, reaffirming the significance of molecular testing to enhance transfusion safety.

The application value of GeneXpert MTB/RIF Ultra in the detection of special specimens of tuberculosis / 中国热带医学

@#Abstract: Objective To compare the diagnostic efficacy of the upgraded version of the GeneXpert automated fluorescent quantitative PCR system (GeneXpert MTB/RIF Ultra, GeneXpert Ultra) and the original version of the GeneXpert system (GeneXpert MTB/RIF, Xpert), real-time fluorescent quantitative nucleic acid detection (FQ-PCR), real-time fluorescent thermostatic amplification of Mycobacterium tuberculosis RNA (SAT-RNA), real-time fluorescent thermostatic amplification detection of DNA (thermostatic amplification method) and traditional BACTEC MGIT 960 liquid culture (culture method) for special specimens of tuberculosis, in order to analyze its application value in clinical detection. Methods Using prospective research methods, a total of 170 special specimens (including 47 pleural and ascites effusion samples, and 34 24-hour urinary sediment specimens, 49 tissue specimens and 40 fester specimens) were collected i'an Chest Hospital from January to September 2021. GeneXpert Ultra, Xpert, FQ-PCR, SAT-RNA, isothermal amplification, and traditional culture were used for detection. Clinical diagnosis was used as the standard, and sensitivity, specificity, positive predictive value, negative predictive value, coincidence rate, and Kappa value were compared among the methods. Results The sensitivities of GeneXpert Ultra, Xpert, FQ-PCR, SAT-RNA, isothermal amplification, and traditional culture were 65.18% (73/112), 49.11% (55/112), 37.50% (42/112), 19.64% (22/112), 8.04% (9/112), and 22.32% (25/112), respectively. The sensitivity of GeneXpert Ultra was higher than that of the other five methods, and the differences were statistically significant (χ2=66.25, 42.10, 28.89, 13.09, 4.92, 15.18, all P<0.05). GeneXpert Ultra result analysis showed that: 5.48%(4/73) cases had trace, that is, trace Mycobacterium tuberculosis load, 79.45% (58/73) cases were extremely low, 10.96% (8/73) cases were low, 2.74% (2/73) were medium, , and 1.36% (1/73) were high load. In 4 trace samples, the Xpert detection was negative for all. Of the 73 GeneXpert Ultra positive reports, 63 were rifampicin-sensitive, 6 were rifampicin-resistant, and 4 were rifampicin-resistant but of unclear resistance. Of the 55 Xpert positive reports, 45 were rifampicin-sensitive, 2 were rifampicin-resistant, and 8 were rifampicinresistant but of unclear resistance.. Conclusions The new generation of GeneXpert MTB/RIF Ultra has high sensitivity, specificity and drug resistance detection rate, and its advantage is even more apparent in the pathogenic diagnosis of special specimens of tuberculosis. It can be used as one of the preferred methods in samples with low bacterial load.

Cost-effectiveness analysis of nucleic acid screening for hepatitis B and C in hospitalized patients in China / 中华检验医学杂志

Objective:To compare the cost-effectiveness of hospitalized Chinese patients undergoing nucleic acid screening strategies for hepatitis B and hepatitis C, immunological screening strategy, and no screening strategy under different willingness to pay (WTP). The results might aid to decision-making for the optimal strategy.Methods:In this study, nucleic acid screening, immunological screening and no screening were used as screening strategies, and China′s GDP in 2021 (80 976 yuan) was used as the threshold of WTP to construct a Markov model. After introducing parameters related to the diagnosis and treatment of hepatitis B and C in inpatients, a cohort population of 100 000 inpatients was simulated by TreeAge Pro 2021 software, the total cost, total health effects, incremental cost-effectiveness ratio and average cost-effectiveness ratio of different screening strategies were calculated, and cost-effectiveness analysis was conducted. Univariate and probabilistic sensitivity analysis were used to assess the impact of parameter uncertainty on the final results.Results:Compared with the non-screening strategy, the incremental total cost of the hepatitis B immunological screening strategy for cohort patients was 11 049 536 yuan, and the incremental cost-effectiveness ratio was 24 762 yuan/quality-adjusted life years (QALY), while the total incremental cost of nucleic acid screening was 19 208 059 yuan, and the incremental cost-effectiveness ratio was 29 873 yuan/QALY; the incremental cost-effectiveness ratio of nucleic acid screening and immunological screening was 45 834 yuan/QALY. Compared with the non-screening strategy, the incremental cost-effectiveness ratio of hepatitis C immunological screening strategy was 5 731 yuan/QALY, the incremental cost-effectiveness ratio of nucleic acid screening strategy was 8 722 yuan/QALY, the incremental cost-effectiveness ratio of nucleic acid screening and immunological screening was 45 591 yuan/QALY. The results of probabilistic sensitivity analysis showed that when the cost of nucleic acid testing exceeded 214.53 yuan, it was not cost-effective to perform hepatitis B nucleic acid screening under the WTP as 1 fold GDP. When the cost of nucleic acid testing exceeded 132.18 yuan, it was not cost-effective to conduct hepatitis C screening under the WTP as 1 fold GDP.Conclusions:Nucleic acid screening strategy can achieve more cost-effectiveness and is worthy of vigorous promotion. Compared with no screening, both the nucleic acid and immunological screening strategies are cost-effective, and hepatitis nucleic acid screening is the optimal strategy for hospitalized patients.

A multicenter study assessing the efficacy of various preoperative/pre-transfusion screening methods for blood transmitted disease / 中华检验医学杂志

Objective:This multi-centre study was conducted to assess the efficacy of various preoperative/pre-transfusion screening methods for blood transmitted disease.Methods:From July 2021 to December 2021, plasma samples of patients admitted to 10 hospitals were collected for screening preoperative/pre-transfusion blood transmitted disease. Nucleic acid detection technology was used to detect hepatitis B virus (HBV) DNA, hepatitis C virus (HCV) RNA and human immunodeficiency virus (HIV)(1+2) RNA, and the results were compared with the immuno-serological methods. χ 2 test and Kappa test were used to analyze the efficacy of these two methods. Results:A total of 8 655 valid specimens were collected from 10 hospitals. There was a statistically significant difference in the positive detection rate of HCV between the two methods ( P<0.001). There was no significant difference in the positive detection rate of HBV and HIV assessed by the two methods ( P>0.05), but the number of positive cases detected by HBV DNA and HIV RNA (218 and 4 cases) was significantly higher than the corresponding serological results (216 and 2 cases). At the same time, there were HBV, HCV and HIV immuno-serological omissions by the immuno-serological methods, among which 28 cases were HBsAg negative and HBV DNA positive, 2 cases were HCV antibody negative and HCV RNA positive, and 2 cases were HIV antigen/antibody negative and HIV RNA positive. In addition, in the 66 samples with inconsistent results from the two detection methods, 83.3% (55/66), 68.2% (45/66), 63.6% (42/66) and 62.1% (41/66) of patients aged was>45 years, tumor, surgery and male, respectively. Conclusions:Compared with immuno-serological tests, nucleic acid tests have the advantage in terms of sensitivity on detecting HBV, HCV and HIV infection and could reduce missed detection. The risk of transmission can be reduced by adding HBV, HCV, and HIV nucleic acid tests to preoperative/pre-transfusion immuno-serological tests screening for patients over 45 years of age and tumor patients.

Clinical value of nucleic acid detection for hepatitis B virus screening in hospitalized patients / 中华检验医学杂志

Objective:To explore clinical value of nucleic acid detection for hepatitis B virus (HBV) screening in hospitalized patients.Methods:This cross-sectional study collected and analyzed plasma samples from patients admitted to 10 domestic medical institutions from July 2021 to December 2021. Serological immunoassay and nucleic acid screening were used to simultaneously detect hepatitis B markers such as hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (HBsAb), hepatitis B e Antigen (HBeAg), hepatitis B e antibody (HBeAb), hepatitis B core antibody (HBcAb),and HBV DNA. Statistical analysis was performed on the serology, nucleic acid test results and clinical information of the patients.Results:Of the 8 655 collected samples, HBsAg was positive in 216 (2.50%) samples,HBV DNA was positive in 238 (2.75%) samples ( P>0.05); 210 (2.43%) samples were positive for both HBsAg and HBV DNA, 28 (0.32%) were HBsAg negative and HBV DNA positive, 6 cases (0.07%) were HBsAg positive and HBV DNA negative. Conclusion:These results indicate that the HBV DNA testing is equally effective as hepatitis B virus serological detection for hepatitis B virus screening in hospitalized patients.

Clinical significance of hepatitis B virus DNA detection in screening patients with hepatitis B / 中华检验医学杂志

Objective:To explore the clinical significance of hepatitis B virus (HBV) DNA detection in screening patients with hepatitis B.Methods:Clinical data of 682 331 hepatitis B patients were retrospectively analyzed. The HBV DNA of these patients was detected in the Fifth Medical Center of the PLA General Hospital from January 2017 to December 2021, there were 481 159 males and 201 172 females in this cohort, the average age was (41.34±16.13) years. Patients were divided into HBV DNA positive group (219 879 cases) and HBV DNA negative group (462 452 cases). Clinical characteristics, data of five serologic markers of hepatitis B and hepatitis B surface antigen quantification (HBsAg-QN), liver function, alpha fetoprotein (AFP) and prothrombin time (PT) results were collected and analyzed and compared between the two groups.Results:The positive rate of HBV DNA was 32.22% (219 879/682 331) in this cohort. Among the different age groups, the positive rate of HBV DNA was the highest (40.34%, 128 038/317 380) in young people aged 18-44 years. The proportion of patients was lower among aged <1, 45-59 and ≥60 years patients in HBV DNA positive group than that in HBV DNA negative group, while the proportion of patients was higher among aged 1-17 and 18-44 years patients in HBV DNA positive group than that in HBV DNA negative group (all P<0.001). Among 2 291 <1-year-old infants tested for HBV DNA, 71 infants were HBV DNA positive. The positive rates of HBV DNA from 2017 to 2021 were 4.86% (27/556), 3.68% (14/380), 3.47% (17/490), 1.55% (6/386) and 1.46% (7/479) respectively, showing a downward trend year by year. The positive rate of HBV DNA in acute hepatitis B (AHB) patients was the highest (49.88%, 208/417) among 680 040 patients with hepatitis B. The proportion of AHB patients (0.09%, 208/219 808) and chronic hepatitis B (80.44%, 176 806/219 808) in HBV DNA positive group was higher than that in HBV DNA negative group [0.05% (209/460 232) and 65.45% (301, 216/460 232)], while the proportion of patients with HBV-related liver cirrhosis (11.28%, 24 793/219 808), HBV-related liver cancer (6.72%, 14 775/219 808), liver cancer surgery (1.39%, 3 055/219 808) and liver transplantation (0.08%, 171/219 808) were lower than that in HBV DNA negative group [22.99% (105 813/460 232), 7.25% (33 385/460 232), 3.50% (16 129/460 232) and 0.76% (3 480/460 232)] (all P<0.001). At the same time, positive rate of hepatitis B surface antigen (HbsAg), HBsAg-QN, hepatitis B e antigen (HbeAg), level of total bilirubin, total bilirubin, AFP and PT were higher in HBV DNA positive group than those in HBV DNA negative group, while the age, male ratio and albumin results in HBV DNA positive group were lower than those in HBV DNA negative group (all P<0.01). The HBV DNA loads were higher in HBsAg positive group, hepatitis B surface antibody positive group and HBeAg positive group than those in respective negative groups, while the HBV DNA loads were lower in hepatitis B e antibody positive group and hepatitis B core antibody positive group than those in respective negative groups (all P<0.001). Conclusions:The mother to child transmission rate of<1-year-old infants decreases year by year. HBV DNA is an important factor for the progression of hepatitis B disease. HBV DNA positive hepatitis B patients with higher HBsAg-QN values are more likely to have abnormal serum markers such as liver dysfunction. HBV DNA detection is therefore of clinical importance in screening patients with hepatitis B.

Clinical value of highly sensitive hepatitis B virus surface antigen and DNA assays / 中华检验医学杂志

For patients with chronic hepatitis B, the indications of antiviral treatment are gradually expanding, and the pursuit of various degrees of cure (partial cure, functional cure and complete cure) is consistently improving, which enhances the urgent clinical need for improving the detection sensitivity of hepatitis B virus (HBV) surface antigen and DNA. Based on the availability of commercial highly sensitive hepatitis B surface antigen and HBV DNA detection reagents, we summarized their applications in the diagnosis of HBV infection, their role on guiding selection of antiviral treatment agents and treatment plans, their prediction efficacy and indication for drug withdrawal, their role on monitoring therapy efficacy and the prediction of disease outcomes. Taken together, highly sensitive hepatitis B virus surface antigen and DNA assays and related detection technology play an important role in the whole management process of chronic HBV infection.

Feasibility and Sensitivity of Saliva GeneXpert MTB/RIF Ultra for Tuberculosis Diagnosis in Adults in Uganda.

The objective of this prospective observational study carried out at China-Uganda Friendship Hospital-Naguru in Kampala, Uganda, was to determine the performance of GeneXpert MTB/RIF Ultra (Xpert Ultra) molecular testing on saliva for active tuberculosis (TB) disease among consecutive adults undergoing TB diagnostic evaluation who were Xpert Ultra positive on sputum. We calculated sensitivity to determine TB diagnostic performance in comparison to a composite reference standard of Mycobacterium tuberculosis liquid and solid cultures on two spot sputum specimens. Xpert Ultra on a single saliva sample had a sensitivity of 90% (95% confidence interval [CI], 81 to 95%) relative to the composite sputum culture-based reference standard, similar to the composite sensitivity of 87% (95% CI, 77 to 94%) for fluorescence microscopy (FM) for acid-fast bacilli on two sputum smears. The sensitivity of salivary Xpert Ultra was 24% lower (95% CI for difference, 2 to 48%; P = 0.003) among persons living with HIV (71%; 95% CI, 44 to 90%) than among persons living without HIV (95%; 95% CI, 86 to 99%) and 46% higher (95% CI, 14 to 77%; P < 0.0001) among FM-positive (96%; 95% CI, 87 to 99%) than among FM-negative (50%; 95% CI, 19 to 81%) patients. The semiquantitative Xpert Ultra grade was systematically higher in sputum than in a paired saliva sample from the same patient. In conclusion, molecular testing of saliva for active TB diagnosis was feasible and almost as sensitive as molecular testing of sputum in a high TB burden setting. IMPORTANCE Tuberculosis is among the leading causes of morbidity and mortality worldwide, in large part because >3 million people go undiagnosed and untreated each year. Sputum has been the mainstay for TB diagnosis for over a century but can be difficult for patients to produce. In addition, the vigorous coughing required during sputum collection can lead to infection of nearby individuals and health workers. In this case-only study, applying the ultra-sensitive GeneXpert MTB/RIF Ultra molecular diagnostic assay to saliva detected 90% of culture-confirmed TB cases among 81 adults who were undergoing TB evaluation at the outpatient department of a general hospital in Uganda and tested sputum GeneXpert MTB/RIF Ultra positive. These results suggest that saliva may be a feasible and sensitive alternative to sputum for TB diagnosis, thereby meeting two key metrics proposed by the World Health Organization in its target performance profile for a nonsputum test for TB.

A collaborative study to establish the national standard for SARS-CoV-2 RNA nucleic acid amplification techniques (NAAT) in Taiwan.

The conventional PCR remains a valuable method to detect the newly emergent coronavirus rapidly and accurately. Our investigation aimed to establish the standard materials of SARS-CoV-2 for NAAT detection. We provided formalin-inactivated SARS-CoV-2 and confirmed RNA copy numbers. In addition, the virus genome was confirmed with whole-genome sequencing and identified as Wuhan/WI04/2019. Seven laboratories were invited for this collaborative study, according to the reporting data, we determined the SARS-CoV-2 with the unit of 6.35 Log10 copies/mL as the national standard. The availability of the national standard (NS) of SARS-CoV-2 will facilitate the standardization and harmonization of SARS-CoV-2 NAAT assays.