Anti-IgG monoclonal antibody [R-PE]

Objective: Unusual clinical course Background: This is a case report of an immunocompromised patient with a history of non-Hodgkin lymphoma and persistent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection who was seronegative and successfully treated with convalescent plasma. Case Report: A 63-year-old woman with a past medical history of non-Hodgkin lymphoma in remission while on maintenance therapy with the anti-CD20 monoclonal antibody, obinutuzumab, tested positive for SARS-CoV-2 via nasopharyngeal reverse transcription polymerase chain reaction (RT-PCR) testing over 12 weeks and persistently tested seronegative for immunoglobulin G (IgG) antibodies using SARS-CoV-2 lgG chemiluminescent micropartide immunoassay technology. During this time, the patient experienced waxing and waning of symptoms, which included fever, myalgia, and non-productive cough, but never acquired severe respiratory distress. She was admitted to our hospital on illness day 88, and her symptoms resolved after the administration of convalescent plasma. Conclusions: As the understanding of the pathogenesis of SARS-CoV-2 continues to evolve, we can currently only speculate about the occurrence of chronic infection vs. reinfection. The protective role of antibodies and their longevity against SARS-CoV-2 remain unclear. Since humoral immunity has an integral role in SARS-CoV-2 infection, various phase 3 vaccine trials are underway. In the context of this pandemic, the present case demonstrates the challenges in our understanding of testing and treating immunocompromised patients.

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has become a public health emergency of international concern. SARS-CoV-2 RNA detection is the diagnostic criterion for coronavirus disease 2019 (COVID-19). Nevertheless, RNA detection has many limitations, such as being time-consuming and cost-prohibitive, and it must be performed in specialized laboratories. Virus antibody detection is a routine method for screening for multiple viruses, but data about SARS-CoV-2 antibody detection are limited. Method Throat swabs and blood were collected from 67 suspected SARS-CoV-2 infection patients at the Affiliated Hospital of Zunyi Medical University and Zunyi Fourth People's Hospital isolated observation departments. Throat swab samples were subjected to SARS-CoV-2 RNA detection by real-time PCR. Blood was used subjected to SARS-CoV-2 IgG/IgM detection by an enzyme-linked immunosorbent assay (ELISA) and gold immunochromatography assay (GICA). Blood underwent C-reactive protein detection by immunoturbidimetry, and white blood cells, neutrophil percentages and lymphocyte percentages were counted and calculated, respectively. Clinical symptoms, age and lifestyle habits (smoking and drinking) in all patients were recorded. Data were analysed using SPSS version 19. The results were confirmed by T and chi(2)tests; correlations with detection results were analysed by kappa coefficients. Odds ratio (OR) and corrected OR values were analysed by logistic regression.P < 0.05 was considered statistically significant. Results Of the 67 patients included in this study, 26 were SARS-CoV-2 RNA-positive. GICA IgM sensitivity was 50.9% (13/26), and specificity was 90.2% (37/41). ELISA IgM sensitivity was 76.9% (20/26), and specificity was 90.2% (37/41). ELISA IgG sensitivity was 76.9% (20/26), and specificity was 95.1% (39/41). The kappa coefficients between RNA detection and ELISA IgG, ELISA IgM, and GICA IgM results were 0.741 (P < 0.01), 0.681 (P < 0.01) and 0.430 (P < 0.01), respectively. Conclusion Among the candidate blood indicators, serum IgG and IgM detected by ELISA had the best consistency and validity when compared with standard RNA detection; these indicators can be used as potential preliminary screening tools to identify those who should undergo nucleic acid detection in laboratories without RNA detection abilities or as a supplement to RNA detection.