ABSTRACT
Background/Case Studies: On December 17th 2021 the U.S Food and Drug Administration published a letter to clinical laboratory staff and health care providers detailing a risk of false Rapid Plasma Reagin (RPR) when using the Bio-Rad Laboratories BioPlex 2200 Syphilis Total & RPR kit in people who had received a COVID-19 vaccination. Specifically, this notice stated that Treponema pallidum particle agglutination (TP-PA) assays did not appear to be impacted by this issue. At our institution it has been observed that since 2018, the positivity rate of syphilis screening with negative confirmatory testing has been dramatically increased from previous years. Curiously a striking number of these positives occurred at the end of the year, mainly October through December. Study Design/Methods: All whole blood (WB) donations from 2011-2021 which demonstrated positive syphilis screening with negative confirmatory testing were evaluated. Screening for syphilis was performed using the Beckman Coulter PK TP Microhemagglutination assay with confirmatory testing using CAPTIA Syphilis (T. pallidum)-G. Results/Findings: There were 77 whole blood donations from 59 unique donors screened positive for syphilis with negative confirmatory testing from 2011-2021 (summarized in table 1). A dramatic increase in the unconfirmed syphilis positivity rate was observed in 2018-2021 (mean: 0.439%) compared to 2011-2017 (mean: 0.024%, unpaired t-test p-value: 0.0010), representing an 18-fold increase in positive screens. Of these 77 donations, 8 donors contributed 26 units (median: 3, range: 2-5) between 2018-2021. Three of these 8 donors made several (6, 31, and 85) WB donations with negative syphilis screening prior to becoming positive. The 5 remaining donors switched back and forth between negative and positive over the course their donation history. Conclusion(s): There has been a statistically significant increase in unconfirmed syphilis positivity rate among whole blood donors at our institute since 2018 when compared to the 7 years prior. Additionally, the positivity rate doubled from 2020 to 2021. No changes were made to the testing assay used during this time period that could explain these results. There appears to be an autumnal peak in unconfirmed positives suggesting a possible environmental trigger such as viral infection or influenza/COVID-19 (for the 2021 increase) vaccination. Further investigation would be needed to confirm such a hypothesis. (Table Presented).
ABSTRACT
Background Acute respiratory distress syndrome (ARDS) is a major complication in patients with severe coronavirus disease in 2019 (COVID-19). COVID-19 convalescent plasma (CCP) has been proposed as a specific therapy for patients with COVID-19. Our goal is to assess changes in oxygenation and inflammatory markers in patients after receiving CCP. Methods This is a retrospective, health system-based, a case-control study comparing hospitalized patients with COVID-19 who received CCP and were discharged (survivors) to patients who died after receiving CCP (non-survivors). We analyzed the severity of ARDS, oxygenation, and inflammatory markers of 295 patients, comparing 202 survivors to 93 non-survivors with COVID-19 who received CCP. Demographic information and laboratory data were collected on the day of the admission (initial), the day of the plasma infusion (D1), and post-infusion days 3, 7, 15, and 30 (when available). Results Survivors were younger (52.48 y versus 64.02 y;p<0.001) with no pre-existing conditions (25.2% versus 13.9%;p=0.03) compared to non-survivors. Severe ARDS (PaO2/FiO2 <100) was predictive of increased mortality after CCP in non-survivors (p<0.001). Survivors with mild (20%) or moderate (46%) ARDS on D1 had a 54% resolution of ARDS on D7 after CCP (p<0.001). After 72 hours of transfusion, supplemental oxygen requirements decreased by 63% of the survivors, compared to 33% of non-survivors (p<0.001). Inflammatory markers, including white blood cells, absolute neutrophils, platelets, C-reactive protein (CRP), lactate dehydrogenase (LDH), and creatinine, improved within three days in survivors after CCP (p<0.05). Baseline findings associated with a poor prognosis on D1 include a lower platelet count (219.02 versus 281.64, p<0.001), higher blood urea nitrogen (BUN) (35.41 versus 21.48, p<0.001), higher creatinine (2.24 versus 1.26, p<0.001), higher D-dimer (5.88 versus 2.46, p<0.001) and elevated lactate dehydrogenase (LDH) (698.3 versus 464.51, p<0.001) when comparing non-survivors to survivors, respectively. After 72 hours post-transfusion, the following changes were remarkable: normalization of creatinine with a mean of 1.07 in survivors versus 1.92 in non-survivors (p<0.001), a significant decrease in CRP improving from 129.27 to 84.25 in survivors versus 139.11 to 130.0 in non-survivors (p<0.001), and lower lactate dehydrogenase (LDH) in survivors (459.47) versus non-survivors (674.56, p<0.001). Conclusion In this retrospective, health system-based, case-control study, we found that the improvement in oxygenation, resolution of ARDS, and reduced inflammatory markers are seen in survivor patients after early COVID-19 convalescent plasma transfusion. These parameters can be used to assess response to COVID-19 convalescent plasma after 72 hours of the transfusion and could help physicians in the decision-making when administering CCP, especially if resources are scarce. [Formula presented] Disclosures: No relevant conflicts of interest to declare.