Humoral and Cellular Immunity to Severe Acute Respiratory Syndrome Coronavirus-2 Vaccination in Patients with Sarcoidosis

Background: The coronavirus disease 2019 vaccine induces both antibody and T-cell immune responses and has been proven to be effective in preventing coronavirus disease 2019, including its severe disease form, in healthy individuals. However, the details of severe acute respiratory syndrome coronavirus-2 immunoglobulin-G antibody responses and severe acute respiratory syndrome coronavirus-2 specific T-cell responses in patients with sarcoidosis are unknown. Aim: To measure and compare antibody responses and T cell responses using enzyme-linked immunosorbent assays and interferon-gamma release assay in sarcoidosis patients infected with coronavirus disease 2019 and vaccinated with CoronaVac. Study Design: A prospective cohort study. Methods: A total of 28 coronavirus disease 2019 polymerase chain reaction test-positive sarcoidosis patients who were infected with severe acute respiratory syndrome coronavirus-2 in the past 6 months and did not have coronavirus disease 2019 vaccination and 28 sarcoidosis patients who were administered with 2 doses of CoronaVac and never had coronavirus disease 2019 were included in this study. The immune response levels of patients were determined by measuring the severe acute respiratory syndrome coronavirus-2 immunglobulinG and interferon-gamma levels in the blood of the patients by the enzyme-linked immunosorbent assays method and interferon-gamma release assay tests, respectively. Results: The mean age of the patients in the COVID-infected group was 48.1 ± 11.3, while the mean age of the patients in the vaccinated group was 55.6 ± 9.32. The mean time elapsed after infection was 97.32 ± 42.1 days, while 61.3 ± 28.7 days had passed since the second vaccination dose. In the COVID-infected group, immunoglobulin-G and interferon-gamma release tests were positive in 64.3% and 89.3% of the patients, respectively. In the vaccinated group, immunoglobulin-G was positive in 10.7% of the patients, and interferon-gamma release test was positive in 14.3%. Conclusion: Innate immune responses are better than adaptive immune responses in patients with sarcoidosis. The coronaVac vaccine is insufficient to generate humoral and cellular immunities in patients with sarcoidosis.

SARS-CoV-2 antibody research in patients with unprovoked pulmonary embolism in COVID-19 pandemic period.

OBJECTIVE: Due to the coronavirus disease 2019 (COVID-19) pandemic, a significant increase has been observed in patients diagnosed with pulmonary embolism (PE) in our clinic. In addition to COVID-19-related PE, the increase in the number of patients with unprovoked or idiopathic PE was also noteworthy. Although it is not surprising that PE due to immobilization was observed in elderly patients and patients with comorbidities at risk for PE during the pandemic, it is important to investigate the increase in the number of unprovoked PE. Thus, we aimed to show that a previous COVID-19 infection may be a risk factor in these patients by examining the presence of severe acute respiratory syndrome-causing coronavirus (SARS-CoV-2) antibodies in patients diagnosed with unprovoked PE. MATERIALS AND METHODS: The participants of the study consisted of 45 consecutive patients who were diagnosed with PE in our clinic, had no risk factors for PE, were considered unprovoked (idiopathic) PE, and had no history of COVID-19. SARS-CoV-2 antibody titers were measured in the serum samples of the patients for detecting immunity as a result of encountering COVID-19. RESULTS: Of the 45 patients diagnosed with PE, 24 (53.3%) patients were diagnosed with computed tomography pulmonary angiogram (CTPA), and 21 (46.7%) patients were diagnosed with perfusion single-photon emission computed tomography (Q-SPECT/CT). Immunity acquired after encountering COVID-19 was checked with the NCP kit, which revealed positive results in 9 (20%) patients. CONCLUSION: It should be kept in mind that some of the patients diagnosed with idiopathic PE during the pandemic may have embolism due to asymptomatic COVID-19. In addition, it is now known that COVID-19 also creates a tendency toward thrombosis in asymptomatic patients.

Investigation of the ongoing pulmonary defects with perfusion-single photon emission computed tomography/computed tomography in patients under anticoagulant therapy for coronavirus disease 2019-induced pulmonary embolism.

OBJECTIVE: It was aimed to reveal the continuing perfusion defect rates in patients with a diagnosis of pulmonary embolism (PE) due to COVID-19 who have completed the third month of anticoagulant therapy but whose symptoms or laboratory elevations continue. METHODS: Patients with COVID-19 who were diagnosed with PE by Q-SPECT-CT between 1 September 2020 and 1 November 2021, who underwent control Q-SPECT/CT were included in the study. Demographic characteristics, laboratory findings, and first and second Q-SPECT/CT evaluation results of the patients were recorded. RESULTS: It was observed that the pulmonary defect continued in Q-SPECT/CT in the third month of anticoagulant treatment in 58.3% of the patients diagnosed with PE due to COVID-19, and new defects developed in 6.3%. The persistence rate of segment defects was higher than that of subsegment defects. It was observed that the defects persisted more frequently in patients with a history of hospitalization due to COVID-19. CONCLUSION: Perfusion defects may still be present in patients diagnosed with PE due to COVID-19 in the presence of persistent dyspnea/chest pain/D-dimer elevation after 3 months of treatment. Perfusion defect persistence rates are higher in defects more proximal to the subsegment level and in people with severe COVID-19, and extended treatment should be considered in these patients.

Investigation of perfusion defects by Q-SPECT/CT in patients with mild-to-moderate course of COVID-19 and low clinical probability for pulmonary embolism.

OBJECTIVE: Pulmonary embolism is a severe source of mortality and morbidity in patients with severe and critical coronavirus disease 2019. It is not yet clear whether the tendency to thrombosis is increased in the mild-to-moderate course of COVID-19. Our research aims to show the clinical benefit of Q-SPECT/CT in diagnosing PD in outpatients treated with mild-to-moderate course of COVID-19 and to determine the frequency of perfusion defects in these patients having relatively lower risk. METHODS: All patients who underwent Q-SPECT/CT with suspicion of embolism were examined retrospectively. Only patients with low clinical probability and mild-to-moderate course of COVID-19 for PE were included in the study. The patients were evaluated comparatively as those with and without perfusion defects. Patients were divided into laboratory suspicion, clinical suspicion, or clinical and laboratory suspicion. RESULTS: In outpatients with mild-to-moderate COVID-19 with low clinical probability for PE, PD without CT abnormality was detected with a rate of 36.6% with Q-SPECT/CT performed for complaints of high D-dimer and/or dyspnea. None of the patients had PD at more proximal level than the segment level. PD with no concomitant CT abnormality was observed with a rate of 56.5% in patients with both clinical and laboratory suspicion. For D-dimer = 0.5 mg/dL cut-off sensitivity is 85%, for D-dimer = 1.5 mg/dL cut-off specificity 81%. CONCLUSION: Thrombosis tendency is also present in outpatients with mild-to-moderate COVID-19, and these patients should also be offered anticoagulant prophylaxis during the COVID-19 period.