Development of sandwich electrochemiluminescence immunosensor for COVID-19 diagnosis by SARS-CoV-2 spike protein detection based on Au@BSA-luminol nanocomposites.

Coronavirus disease (COVID-19) is a new and highly contagious disease posing a threat to global public health and wreaking havoc around the world. It's caused by the Coronavirus that causes severe acute respiratory syndrome (SARS-CoV-2). In the current pandemic situation, rapid and accurate SARS-CoV-2 diagnosis on a large scale is critical for early-stage diagnosis. Early detection and monitoring of viral infections can aid in controlling and preventing infection in large groups of people. Accordingly, we developed a sensitive and high-throughput sandwich electrochemiluminescence immunosensor based on antigen detection for COVID-19 diagnosis (the spike protein of SARS-CoV-2). For the spike protein of SARS-CoV-2, the ECL biosensor had a linear range of 10 ng mL-1 to 10 µg mL-1 with a limit of detection of 1.93 ng mL-1. The sandwich ECL immunosensor could be used in early clinical diagnosis due to its excellent recovery in detecting SARS-CoV-2, rapid analysis (90 min), and ease of use.

Changes of Routine Hematological Parameters in COVID-19 Patients: Correlation with Imaging Findings, RT-PCR and Outcome.

BACKGROUND & OBJECTIVE: Coronavirus disease 2019 (COVID-19) is progressively spreading, and many researchers have focused on the prognostic value of laboratory analyses. This study reviewed routine blood parameters, upper respiratory viral load, and chest imaging in recovered and expired COVID-19 patients and evaluated possible correlations. METHODS: In this retrograde study, 138 COVID-19 cases were enrolled. Chest tomography scores of patients, routine hematologic and biochemical parameters, and respiratory viral loads were measured. Furthermore, their correlation with severity of disease and the outcome was investigated during a week of admission. RESULTS: The mean age of participants was 58.6±16; 36.2% of whom were diagnosed as critical, 8.7% expired, and 46% showed less than 50% lung opacity. The expiring rate was only correlated to the severity of illness and viral load. During admission, hemoglobin concentration was decreased in critical patients (from 11.49±0.27 to 10.59±0.36, P=0.042) and also among CT-scan scoring groups (P=0.000), while neutrophils (P=0.04), WBC (P=0.03), and platelets (P=0.000) count were increased. In patients with more than 50% lung opacity, leukocyte counts were decreased, but neutrophil and platelets counts showed raise (all P<0.05), while other hematologic parameters did not change. CRP and LDH demonstrated no increase based on the severity of the illness, RT-PCR viral loads and/or outcome. However, both CRP and LDH were increased in patients with more than 50% lobal opacity (CRP: 69.3±9.9 to 1021.1±7.5 and LDH:589.5±93.2 to 1128.6±15.81, P<0.05). CONCLUSION: We found that hemoglobin, white blood cells, neutrophil, lymphocytes, and platelets count together with chest tomography score might be beneficial for expedition the diagnosis, assessmen the severity of the disease, and outcome in the hospitalized cases, while CRP and LDH might be considered as the consequence of lung involvement.

Diagnostic Utility of Combined CEA, CA15-3 and CA125 Biomarkers and Cytomorphology in Suspicious and Malignant Serosal Fluid.

BACKGROUND & OBJECTIVE: Early detection of malignancies in the serous fluids has been remained an issue. A classic diagnostic tool for the ascites and pleural effusions is cytologic study (morphology) with approximately 98% specificity for the detection of cancer cells. This study aimed to evaluate the diagnostic value of three complementary markers in the serosal fluids of patients with malignant cytology and suspected cases. METHODS: Seventy two patients with serosal effusion treated in three teaching hospitals were studied. The cases underwent a diagnostic workup to determine the pleural effusion malignancy and etiologies. Complementary markers, including CEA, CA15-3, and CA125 were measured in serosal fluids of three categories of benign, suspicious, and malignant. The study was carried out by Chemiluminescence immunoalayzer. The morphologies were re-evaluated by a consulting Cytopathologist. RESULTS: Of 72 serosal fluid specimens, 41 (56.9%) were related to pleural effusion and 31 (43.1%) were related to ascites. The sensitivity of CEA, CA125, and CA15-3 biomarkers were 64, 84, and 68%, respectively, and the specificity of each test was 100, 86, and 96%, respectively. This was statistically achieved for the combination of the area of markers below the curve (AUC), 0.93 and 90% sensitivity and 91% specificity. CONCLUSION: The results suggest that complementary CA125, CA15-3, and CEA markers assayed with well-developed immunoassay method might be useful in the differentiation between malignant and benign effusions while combined with conventional cytology. CA125 yielded a significant correlation between cytomorphology and biomarkers based on the correlation coefficient analysis.