Messenger ribonucleic acid vaccine-associated immune thrombocytopenia: A rare complication of vaccine.

Coronavirus disease-2019 continues to have a serious impact in countries with the effect of new variant viruses emerging with mutations. While the effectiveness and protection of the vaccine have been determined all over the world, some vaccine-related side effects can be detected in the form of cases. In our case, the patient was admitted to the emergency department of our hospital with complaints of weakness and progressive rash on his legs. Diffuse petechiae purpura on the legs of the patient was observed and complete blood count revealed thrombocytopenia. Peripheral blood smear supported the blood count test results with thrombocytopenia, secondary causes of thrombocytopenia were excluded, and the patient was diagnosed with vaccine-induced immune thrombocytopenia.

Measurement of antibody levels in patients with COVID-19 over time by immunofluorescence assay: a longitudinal observational study.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic, antibody screening is a critical tool to assess anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunity. We examined variation in antibody titers associated with age and sex among patients with confirmed COVID-19. METHODS: Blood IgG levels were tested in 1081 patients with positive SARS-CoV-2 quantitative reverse transcription polymerase chain reaction (RT-qPCR) tests between 1 September and 31 December 2020. Patients who did not experience reinfection were identified. Serum IgG levels were measured by immunofluorescence assay. Antibody positivity and antibody titers were analyzed according to time since infection, sex, and age. RESULTS: The mean (standard deviation) age was 41.2 (14.2) years and 41.2% of patients were women. The lowest antibody positivity rate between the first and ninth month post-infection was detected in the sixth month. The lowest antibody titers among patients aged 20 to 80 years occurred in those aged 30 to 39 years. The IgG titer was positively correlated with age in years (r = 0.125) and decades (r = 0.126). CONCLUSIONS: Six months after infection, anti-SARS-CoV-2 antibody titers increased. Anti-SARS-CoV-2 antibody titers also increased with age. Immunity and pathogenicity should be investigated in addition to antibody positivity rates and antibody titers.

Does the COVID-19 seroconversion in older adults resemble the young?

High antibody titers have been found to correlate with the severity of coronavirus disease 2019 (COVID-19) disease. Therefore, antibody titers may be higher in older adults, whose disease is known to have a more severe course than younger ones. This study aimed to compare the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) antibody level in the reverse transcription-polymerase chain reaction (RT-PCR) to test positive older adults with young. Patients aged ≥18 with positive RT-PCR and checked serum IgG antibodies between November 1, 2020 and January 13, 2021 were included. The IgG antibody levels and the time between RT-PCR positivity with the antibody levels were recorded. A total of 1071 patients were divided into two groups as Group 1 <60 years old (n = 902) and Group 2 ≥60 years old (n = 169). The SARS-CoV-2 IgG antibody titers were higher in Group 2 (p = 0.001). This height was present in the first 3 months after positive RT-PCR. While the antibody titers were compared by dividing Group 2 into the three groups according to age ranges (60-69, 70-79, and ≥80 years), the antibody titer was higher in ≥80 years patients (p = 0.044). High COVID-19 IgG antibody levels may be associated with the severity of the disease. Also, the humoral immunity advantage was seen in the first 3 months in the older patients, which suggests that older adults with COVID-19 may develop reinfection in the long term.