Discordant Predictions of Extraglandular Involvement in Primary Sjögren’s Syndrome According to the Anti-SSA/Ro60 Antibodies Detection Assay in a Cohort Study

Electrophoresis-derived techniques for anti-SSA/Ro60 KDa (anti-SSA) antibodies detection have been progressively replaced by methods using non-native antigens. We aimed to compare the patients’ phenotypes and the occurrence of extraglandular manifestations in primary Sjögren’s syndrome according to the method used to detect anti-SSA antibodies. Sera from patients with a diagnosis of pSS according to ACR/EULAR 2016 criteria between 2008 and 2017 were tested for anti-SSA antibodies using methods with non-native antigens (magnetic bead multiplex assay; line immunoassays) and one with native antigens (counterimmunoelectrophoresis (CIE)). The population was split into three groups according to anti-SSA antibodies status: absence (SSA−), presence in any method except for CIE (SSA+CIE−), and presence in CIE (SSA+CIE+). The patients in the SSA+CIE+ group (n = 70, 42.7%) were ten years younger and presented more immunological activity compared with both the SSA− (n = 80, 48.8%) and SSA+CIE− groups (n = 14, 8.5%). The SSA− and SSA+CIE− groups were poorly distinct. The presence of anti-SSA antibodies solely in CIE was significantly associated with the occurrence of extraglandular manifestations of pSS (HR = 4.45 (2.35–8.42)). Contrary to CIE, methods using non-native antigens to detect anti-SSA antibodies were unable to predict the occurrence of systemic expression of pSS.

Comparative Evaluation of SARS-CoV-2 Rapid Immunochromatographic Test Assays with Chemiluminescent Immunoassay for the Diagnosis of COVID-19

Background To date, the molecular assay is the gold-standard method for COVID-19 diagnosis. However, they are expensive and complex. There is a pressing necessity for developing other effective diagnostics for SARS‐CoV‐2 patients. Therefore, serological detection of antibodies against SARS‐CoV‐2 might provide a good alternative. Aim We aimed to compare and evaluate seven rapid diagnostic tests with Mindray chemiluminescent automated immunoassay as a reference method for SARS-CoV-2 antibodies detection. Methods: This study included the serum of a total of 49 attendees to the Reference Laboratory of Egyptian university hospitals during the period from April 2021 to May 2021. Anti-Covid-19 antibodies detection in serum samples was performed by Mindray fully automated system as our reference method and seven rapid antibody tests; Wondfo, Vazyme, Dynamiker, Panbio, Artron Maccura and Roche. Results: The chemiluminescent assay revealed 30 (61.2%) positive samples and 19 (38.8%) negative samples for COVID-19 IgG. For COVID-19 IgM, 11 (22.4%) samples were positive and 38 (77.6%) samples were negative. Anti-SARS-CoV-2 antibodies were not detected in any of the PCR negative individuals. The best diagnostic performance was demonstrated by Roche IgG and IgM, and Vazyme IgG and IgM antibody tests followed by Panbio. For Roche, the sensitivity and specificity for IgG and IgM were (83.3%, 89.5%) and (72.7%, 81.6%) respectively. Vazyme showed sensitivity and specificity for IgG and IgM were (77.8%, 85.7%) and (75%, 91.7%) respectively. Regards Panbio, the sensitivity and specificity for IgG and IgM were (63.6%, 87.5%) and (50%, 86.7%) respectively. Cohen’s Kappa values revealed a substantial agreement for Roche IgG, Vazyme IgG and IgM of (0.7076, 0.6250, 0.6667) respectively. The worst agreement was reported for Maccura IgG, Wondfo, and Dynamiker IgM with Cohen’s Kappa values of (0.2508, 0.1893, 0.0313) respectively. Conclusions: Rapid tests in our study exhibited heterogeneous diagnostic performances. Roche, Vazyme, and Panbio antibody tests showed promising results in concordance with our reference method with the best-reported results. On the other hand, the other tests were inferior and failed in providing valid and reliable results. Further studies are necessary to determine the practicality of these tests in different settings and communities.

In vitro methods for rabies virus detection, and evaluation of their use in the production of rabies immunoglobulin

Current highly sensitive methods for rabies virus and rabies antibodies detection in biological material can be used not only for diagnosis and experimental research, but also for the production of antirabies medicines used for postexposure prophylaxis. The aim of the study was to analyse existing methods for rabies virus and rabies antibodies detection and to assess the potential for using these methods at the control stages during production of heterologous antirabies immunoglobulin obtained from equine serum. The search for cutting-edge highly sensitive in vitro control methods that could compete with the biological method, which is the main method used in antirabies immunoglobulin control, is an important prerequisite for improvement of the production technology and the quality of antirabies medicines. The study demonstrated that the following test methods can be used in the production of antirabies immunoglobulin: fluorescent antibody technique, enzyme-linked immunosorbent assay, cell culture methods, atomic force microscopy, and flow cytometry. These methods could be used alone or as an alternative to the biological method in white mice. These methods were chosen because of their high sensitivity, specificity, rapid and easy implementation, cost-effectiveness, and automatic recording of test results.

Detection of SFTS Virus RNA and Total Antibodies in Wild Animals, Jiangsu, China, 2014-2019

Background Severe fever with thrombocytopenia syndrome (SFTS) is a novel infectious disease caused by severe fever with thrombocytopenia syndrome virus (SFTSV). Currently, SFTS is endemic to some areas in China, and wild animals are considered to play important roles in the circulation of SFTSV in the environment. Wild animals monitoring for SFTSV has been fulfilled since 2014 in Jiangsu Province. We studied the results of the detection to provide basic data for better diagnosis of wild animals. Methods This research was conducted in Jiangsu Province from 2014 to 2019. Sera of wild animals (Rodents, pheasants and hedgehogs) were collected to detect SFTSV both RNA and total antibodies by qRT-PCR and enzyme-linked immunosorbent assay. Statistical analysis was performed by using SPSS 25.0 (Chicago, IL, USA).Results A total of 95.8% (1298/1355) of the specimens had the same SFTSV RNA and total antibodies detection results. However, there was a significant difference between the detection rates of SFTSV RNA and total antibodies, and the detection consistency was very poor. The detection rate of SFTSV total antibodies was highest in hedgehogs(19.54%).Conclusions SFTSV total antibodies testing was preferred method during wild animals surveillance. Also, hedgehog could be a competent reservoir for SFTSV.

Antineutrophil Cytoplasmic Antibodies in Patients Treated With Methimazole

Introduction: Antithyroid drugs (ATDs) are widely used for the treatment of hyperthyroidism. Most side effects of these medications are mild and emerge within the first months of treatment. In contrast, antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis is a severe adverse event whose occurrence increases with increasing time of treatment. Vasculitis is more frequently associated with propylthiouracil than with methimazole, but the latter has also been related to the occurrence of ANCA and even to clinically manifest vasculitis. Many patients develop ANCA during treatment with methimazole but do not exhibit signs/symptoms of vasculitis. Objective: We previously reported a relatively high frequency (20%) of ANCA in patients exposed to methimazole but none of them exhibited clinical manifestations of vasculitis on that occasion. We continued to follow up these patients with ANCA and report here their evolution after 2 years. Methods: Seventeen patients exposed to methimazole were followed for 2 years after antibodies detection (ANCA). Results: Eight patients had ANCA but had not used methimazole for at least 6 months. During the following 24 months, continuing without ATD, none of the patients developed clinically apparent vasculitis. In the last assessment, five patients no longer had ANCA, while these antibodies persisted in three. Nine patients had ANCA and had been on methimazole for at least 6 months. The medication was not immediately discontinued in these patients when the antibodies were detected. After this detection, treatment with methimazole was continued in these patients for more 3 months (n = 1), 6 months (n = 2), 9 months (n = 1), 12 months (n = 2), 18 months (n = 2), and 24 months (n = 1). During the 2 years of follow-up after the detection of ANCA, none of the 9 patients developed signs/symptoms of vasculitis. In the last assessment, ANCA were negative in two patients who had received methimazole for more 3 and 6 months and who were therefore without receiving the drug for 21 and 18 months, respectively. The other 7 patients remained ANCA positive. Conclusion: Although vasculitis is necessarily associated with the presence of ANCA, the inverse frequency is undefined and appears to be low. Thus, measurement of ANCA would not be recommended in asymptomatic patients during methimazole treatment and immediate discontinuation of this drug, if these antibodies are detected eventually, may not be required. Reference: Antineutrophil cytoplasmic antibodies in patients treated with methimazole: a prospective Brazilian study. Andrade GC, Maia FCP, Mourão GF, Rosario PW, Calsolari MR. Braz J Otorhinolaryngol. 2019; 85:636-41.