1005. COVID-19 At-Home Capillary Blood Specimen Collection Pilot – Gaining Insight into Independent Self- Collection of Blood Specimens and COVID-19 Within the Veteran Population

Background The VA Million Veteran Program (MVP) studies what factors influence Veteran health. Current procedures involve collection of venous blood at MVP enrollment sites. To examine home specimen collection options, MVP performed a pilot study comparing two blood specimen collection devices and evaluated SARS-CoV-2 antibody assays to determine known COVID-19 infection or vaccination. Methods A sub-sample of MVP Veteran participants were asked to self-collect a capillary blood specimen using the Neoteryx Mitra Clamshell (up to 120uL dried blood) or Tasso-SST (up to 200uL liquid blood) per the vendor instructions. Veterans were randomly assigned to a device prior to consent. Eligibility included 30% of Veterans with known COVID-19 diagnosis or vaccination and sampling time was variable from these events. Veterans rated their device experience and shipped collected specimens directly to an MVP laboratory. Mitra tip (4) blood was eluted in 1 mL of 0.9% normal saline for 1 hour at room temperature shaking at 300 rpm. Tasso tubes were centrifuged per vendor instructions. All samples were stored at -80°C until tested with SARS-Cov-2 antibody (Ab) assays (InBios Spike IgG, BioRad Nucleocapsid (NC) Total Ab, Abbott NC IgG, and Abbott Spike IgG II) per vendor instructions. Results 312 MVP participants consented to the pilot (52%) of which 136 (43.6%) were sent Mitra and 176 (56.4%) were sent Tasso-SST (Table 1). Participants rated the Mitra Tasso-SST equally on average as 4.4 on a 0-5 usability scale. The Abbott IgG II assay had the highest sensitivity across both devices (87% Mitra and 98% Tasso-SST) for detecting known COVID infection and/or vaccination. The InBios IgG assay with the Tasso-SST had the best sensitivity (97%) and specificity (80%) for detecting known COVID-19 infection and/or vaccination (Table 2). Table 1. COVID-19 At-Home Capillary Blood Specimen Collection Pilot Outcomes Conclusion Veterans successfully collected their own specimens and had no strong preference for either device. The Tasso-SST combined with the InBios Spike IgG assay provided the highest combination of sensitivity and specificity. Limitations included one collection device per subject, varied timing of testing, unknown infection or vaccination status among some, and Tasso collection volume and Mitra whole blood dilution may have affected comparison across assays or performance. Disclosures All Authors: No reported disclosures

Cold antibodies association with cellulitis, deep vein thrombosis and abnormal red cells indices: A Case Report.

Objectives: To provide awareness to the pathologists and technologists all about the red cells parameters in cold antibodies concerned cases. Case Report Findings: A sixty seven-years-old male admitted in emergency department of our hospital, having clinical history of swelling and pain in both the lower limb and feet, on physical examination, provisionally diagnosed as a case of Cellulitis and deep vein thrombosis(DVT). Blood specimen was obtained for general hematological investigations. Full blood count (FBC) was performed on sysmex XP-100 hematological analyzer which showed invalid findings especially red cells indices which were not corresponding to the hemoglobin (Hb) concentration of the patient. Blood sample was repeated, to confirm invalid red cells indices which showed values as in the 1st blood specimen. Blood smears revealed aggregation of red cells. By warming the ethylenediamine tetra-acetic acid (EDTA) tube containing the blood specimen, in water bath at 37⁰C for one hour and repeated the FBC on hematological analyzer and found the corrected red cells indices. Conclusion: Basic knowledge of cold antibodies and warming the blood sample at 37⁰c for one hour helps the correct diagnosis.

Optimizing Real-Time PCR methods for detection of ssaN gene Salmonella enterica subsp.enterica in the blood specimen

Background Typhoid fever caused by Salmonella typhi is a common acute infection of the reticuloendothelial system, intestinal lymphoid tissue, and gall bladder. Detection of Salmonella spp. is still based on cultures and serological methods.Widal test is one of the serological tests that is still widely used, especially in developing countries including Indonesia.Widal tests have low sensitivity and specificity. They often produce false positive or false negative results.ObjectiveThe aim of this study were i) real time PCR optimization to develop a Salmonella enterica detection system. ii) molecular detection of new target gene (ssaN gene) from blood specimens in typhoid fever patients.Methods An experimental laboratory study was performed from March to October 2016. Extraction of Salmonella typhi DNA is used as templates for the optimization of real time PCR reaction.The blood sample was from patients suspected with typhoid fever obtained from the Menteng Sub-district Health Center according to the inclusion criteria.ResultsSpecificity test of real time PCR showed that the primers and probes used are not cross-react against other microorganisms. Sensitivity test obtained minimal detection is at least 10 cfu/ml of blood specimen. In blood clinical specimens, real time PCR could detect 19 (38%) positive samples of 50 blood specimen from suspected typhoid fever patients. Eleven samples with negative Widal serology gives positive results in real time PCR.ConclusionReal time PCR used in this study can increase the level of rate of positive testing by 22% of the total specimens.Keywords : Salmonella enterica subsp.enterica, typhoid fever, ssaN gene, real time PCR