Prospective Observational COVID-19 Screening and Monitoring of Asymptomatic Cancer Center Health-Care Workers with a Rapid Serological Test.

Health-care workers (HCW) are at high risk for SARS-CoV-2 infection and, if asymptomatic, for transmitting the virus to fragile cancer patients. We monitored all asymptomatic HCWs of a cancer institute (94% of all employees agreed to enter the study) with the rapid serological test, VivaDiagTM, identifying SARS-CoV-2 associated-IgM/IgG. The tests were performed at time 0 (n = 606) and after 14 days (n = 393). Overall, the VivaDiagTM results of nine HCWs (1.5%) were positive, with one confirmed to be SARS-CoV-2-positive after oropharyngeal swab testing by RT-PCR. At time 0, all nine cases showed IgM expression while IgG was detected in only one. After 14 days, IgM persisted in all the cases, while IgG became evident in four. A chemiluminescence immunoassay (CLIA) confirmed IgM positivity in 5/13 VivaDiagTM positive cases and IgG positivity in 4/5 VivaDiagTM positive cases. Our study suggests that the VivaDiagTM test can be of help in identifying SARS-CoV-2 infected people in cohorts of subjects with a high prevalence.

Rapid Serological Assays and SARS-CoV-2 Real-Time Polymerase Chain Reaction Assays for the Detection of SARS-CoV-2: Comparative Study.

BACKGROUND: Real-time polymerase chain reaction (RT-PCR) testing for the identification of viral nucleic acid is the current standard for the diagnosis of SARS-CoV-2 infection, but technical issues limit its utilization for large-scale screening. Serological immunoglobulin M (IgM)/IgG testing has been proposed as a useful tool for detecting SARS-CoV-2 exposure. OBJECTIVE: The objective of our study was to compare the results of the rapid serological VivaDiag test for SARS-CoV-2-related IgM/IgG detection with those of the standard RT-PCR laboratory test for identifying SARS-CoV-2 nucleic acid. METHODS: We simultaneously performed both serological and molecular tests with a consecutive series of 191 symptomatic patients. The results provided by a new rapid serological colorimetric test for analyzing IgM/IgG expression were compared with those of RT-PCR testing for SARS-CoV-2 detection. RESULTS: Of the 191 subjects, 70 (36.6%) tested positive for SARS-CoV-2 based on RT-PCR results, while 34 (17.3%) tested positive based on serological IgM/IgG expression. Additionally, 13 (6.8%) subjects tested positive based on serological test results, but also tested negative based on RT-PCR results. The rapid serological test had a sensitivity of 30% and a specificity of 89% compared to the standard RT-PCR assay. Interestingly, the performance of both assays improved 8 days after symptom appearance. After 10 days had passed since symptom appearance, the predictive value of the rapid serological test was higher than that of the standard molecular assay (proportion of positive results: 40% vs 20%). Multivariate analysis showed that age >58 years (P<.01) and period of >15 days after symptom onset (P<.02) were significant and independent factors associated with serological test positivity. CONCLUSIONS: The rapid serological test analyzed in this study seems limited in terms of usefulness when diagnosing SARS-CoV-2 infection. However, it may be useful for providing relevant information on people's immunoreaction to COVID-19 exposure.

Thyroglobulin Determination in Fine Needle Aspiration Biopsy Washout of Suspicious Lymph Nodes in Thyroid Carcinoma Follow up.

BACKGROUND: Differentiated thyroid carcinomas (DTCs) account for about 1% of all human malignancies. Cervical lymph nodes metastases and recurrences in the thyroid bed frequently occur. Furthermore, about 10-15% of patients develop distant metastases. Therefore, patients must undergo life-long follow-up. OBJECTIVE: The aim of this study was to evaluate the usefulness of Thyroglobulin measurement in FNAB washout (FNAB-Tg) in the detection of local metastasis in patients affected by or evaluated for thyroid cancer. MATERIALS AND METHODS: In a 3-year period, a total of 83 consecutive patients coming to our attention at the Ear-Nose-Throat (ENT) Outpatients Service of the National Cancer Research Center &quot;Istituto Tumori Giovanni Paolo II&quot; of Bari, Italy, because of the finding of one or more cervical lymph node(s), were enrolled in the study. After collection of the cytological specimen, the needle used for performing FNAB was then washed in 1 ml of normal saline. 89 FNAB washouts were collected from the same number of lymph nodes and subsequently investigated for Thyroglobulin levels using a sequential chemiluminescent-immunometric assay. RESULTS: Comparing the cytological or, when performed, histological diagnoses with the results of FNAB-Tg, we found that in 24 cases of lymph node metastases from PTC (19 lymph nodes from patients at the first diagnoses and 5 lymph nodes from PTC patients in follow up) the mean level of Thyroglobulin was 1840.11 ng/ml; range: <0,2 to 11440 ng/ml. In the group of PTC patients (27 lymph nodes) with lymph nodes negative for metastatic involvement at cytology (i.e. no lymph node recurrence at follow-up), as well as in the cases of subjects without PTC and submitted to FNAB because of the appearance of lymph node(s) classified as reactive at cytology (37 lymph nodes), FNAB-Tg was lower than or equal to 0.2 ng/ml. As expected, the Thyroglobulin level was not detectable (< 0.2 ng/ml) also in a lymph node FNAB from a case of anaplastic thyroid carcinoma. CONCLUSION: In our study, FNAB-Tg was not detectable in all node negative patients showing, when considering together all the lymph node metastases, a 96% sensitivity and 100% specificity.