SARS-CoV-2 S-RBD IgG & Neutralizing antibodies among different categories of health care workers post third dose BNT162b2 mRNA COVID-19 vaccine.

Neutralizing antibodies (NTAb) play a significant role in preventing and protecting against SARS-CoV-2 virus infection. Identifying NTAb is undoubtedly imperative in understanding the immunity toward COVID-19 better. However, it is interesting to note that the production of NTAb varies among individuals, especially among healthcare workers (HCWs), as they are exposed to the virus daily. Hence, we would like to investigate factors affecting the production of S-RBD IgG and NTAb among different categories of HCWs, particularly after receiving the third dose of the BNT162b2 mRNA COVID-19 Vaccine. A total of 361 HCWs from our hospital were prospectively enrolled and had their S-RBD IgG and NTAb titers measured. They were studied in relation to the degree of exposure to COVID-19, breakthrough infections, gender, age, race, household income, housing type, household number, and education levels. HCWs with the highest risk of exposure to COVID-19, breakthrough infections, and male gender displayed the highest median titers of both S-RBD IgG and NTAb, and the differences were statistically significant (p < .05). Age, race, household income, housing type, household number, and education levels were revealed to be insignificant. We concluded that the degree of exposure to COVID-19, breakthrough infections, and male gender are significant factors in NTAb production among HCWs.

Utility of PIVKA-II and AFP in Differentiating Hepatocellular Carcinoma from Non-Malignant High-Risk Patients.

Background and Objectives: We aim to compare the diagnostic performance of Protein induced by vitamin K absence-II (PIVKA-II), a biomarker for hepatocellular carcinoma (HCC), and alpha-fetoprotein (AFP) in differentiating HCC and non-malignant high-risk (NMHR) groups and to determine their cut-off values. Materials and Methods: A total of 163 patients, including 40 with HCC and 123 with NMHR (100 with liver cirrhosis and 23 with non-cirrhotic high-risk patients) were prospectively enrolled. The levels of AFP and PIVKA-II were measured, and their cut-off values were determined. We calculated and compared the areas under the receiver operating characteristic (AUROC) curves of PIVKA-II, AFP, and their combination. Results: The levels of PIVKA-II and AFP were found to be significantly higher in the HCC compared to NMHR patients (p < 0.0001). For the differentiation of HCC from NMHR, the optimal cutoff values for PIVKA-II and AFP were 36.7 mAU/mL (90% sensitivity; 82.1% specificity) and 14.2 ng/mL (75% sensitivity; 93.5% specificity), respectively. The AUROC of PIVKA-II (0.905, p < 0.0001) was higher compared to AFP (0.869, p < 0.0001), but the combination of PIVKA−II and AFP gave the highest AUROC value (0.911, p < 0.0001). However, their differences were not statistically significant (AFP vs. PIVKA; p = 0.4775, AFP vs. Combination; p = 0.3808, PIVKA vs. Combination; p = 0.2268). Conclusions: PIVKA-II and AFP showed equal performance in detecting HCC in high-risk patients. AFP as a screening marker for HCC may be adequate, and replacing or adding the PIVKA-II test in current clinical practice may be of little value.