Resolution of Misleading COVID-19 Vaccination-Related Nodal and Splenic FDG Uptake in the Follow-up Study.

ABSTRACT: Newly diagnosed low-grade bilateral breast lymphoma in 63-year-old woman demonstrated intense FDG uptake in the left axillary lymph nodes and the spleen, concerning for lymphomatous involvement. Subsequent ultrasound-guided biopsy did not demonstrate any pathologic left axillary lymph nodes. Further investigation revealed COVID-19 vaccination in the left arm, 5 days prior to the 18 F-FDG PET/CT study. Six-month follow-up 18 F-FDG PET/CT showed resolution of the intense FDG uptake in the left axillary lymph nodes and spleen without any treatment, suggesting a self-remitting acute local and systemic immune response to COVID-19 vaccination.

Does COVID-19 cause an increase in spleen dimensions? Possible effects of immune activation, hematopoietic suppression and microthrombosis.

PURPOSE: To radiologically examine how the spleen size, which has important functions in hematological and immunological balance, is affected in COVID-19. METHODS: Between July 1 and August 31, 2020, consecutive patients diagnosed with COVID-19 were analyzed. Among these patients, those who underwent chest computed tomography (CT) examination at the time of presentation, patients with follow-up CT due to clinical deterioration were included in the study. The CTs of the patients were evaluated in terms of spleen size and volume. RESULTS: A total of 160 patients (88 females, 55%) were included in the study. The mean time between the initial and follow-up CT was 7.2 ± 2.8 days. The splenic volume (244.3 ± 136.7 vs. 303.5 ± 156.3 cm3) and splenic index (421.2 ± 235.5 vs. 523.2 ± 269.4 cm3) values were significantly higher in the follow-up CT compared to the initial CT (p < 0.001). The increase in the splenic volume and splenic index values was 59.2 ± 52.4 cm3 and 101.9 ± 90.3 cm3 (p < 0.001), respectively. The COVID-19 severity score was significantly higher in the follow-up CT compared to the initial CT (3.7 ± 4.2 vs. 12.5 ± 5.7, respectively; p < 0.001). The spleen width measured separately on the initial and follow-up CTs showed a highest positive correlation (r = 0.982, p < 0.001). CONCLUSION: Our study indicates that spleen size increases slightly-moderately in the first stages of the infection, and this increase is correlated with the COVID-19 severity score calculated on the chest CT data, and in this respect, it is similar to infections presenting with cytokine storm.

Splenoportal-mesenteric axis thrombosis and splenic artery occlusion as initial presentations of COVID-19 disease.

OBJECTIVE: Although pulmonary involvement represents the primary and most characteristic presentation of Sars-Cov-2 infection, due to its innate tropism for endothelium, it is also associated with systemic pro-coagulative changes and thromboses. This paper describes a COVID-19 atypical presentation with massive thrombotic occlusion of the splenoportal-mesenteric axis and the splenic artery in the absence of clinical or radiological manifestation of pulmonary involvement. PATIENTS AND METHODS: Female patient, with no history of disease, trauma or fever in the last 30 days, was admitted to ER for persistent left subcostal pain. Laboratory exams, including inflammation, coagulation markers and Sars-CoV-2 serology, were requested. Whole-body CT with contrast media injection was performed. RESULTS: Laboratory exams showed elevated reactive C-protein, bilirubin, γ-GT and D-dimer. Whole-body CT showed: splenic artery occlusion, thrombosis of splenic, mesenteric and portal veins with portal intra-hepatic branches ectasia, juxta-hilar portal cavernomatosis of probable acute onset (absence of signs of chronic hepatopathy and of varices), a hypodense area in the spleen indicating ischemic parenchymal suffering. The patient resulted positive for Sars-CoV-2 IgG, thus in the absence of typical clinics or pulmonary parenchymal abnormality at chest CT. CONCLUSIONS: A case of acute venous thrombosis and arterial occlusion as primary manifestations of COVID-19.

Evaluation of systemic involvement of Coronavirus disease 2019 through spleen; size and texture analysis

Background/aim: To investigate the changes in the spleen size, parenchymal heterogeneity, and computed tomography (CT) texture analysis features of patients diagnosed with Coronavirus disease 2019 (COVID-19) Materials and methods: The size and parenchymal structure of the spleen in 91 patients who underwent thoracic CT examination due to COVID-19 were evaluated. For the evaluation of parenchymal heterogeneity, CT texture analysis was performed using dedicated software (Olea Medical, France). The texture analysis of each case consisted of 15 first-order intensity-based features, 17 gray level co- occurrence matrix-based features, and 9 gray level run length matrix-based features. Results: A total of 91 patients (45 males, 46 females) with a mean age of 54.31 ± 16.33 years (range: 18­81) were included in the study. A statistically significant decrease in spleen size was seen in the follow-up CT examinations (p < 0.001) whereas no statistically significant difference was found between the Hounsfield unit (HU) values. The radiomics consisted of first-order intensity-based features such as 90th percentile, maximum, interquartile range, range, mean absolute deviation, standard deviation, and variance, all of which showed statistically significant differences (p-values: < 0.001, < 0.001, 0.001, 0.003, 0.001, 0.001, and 0.004, respectively). "Correlation" as a gray level co-occurrence matrix-based feature and "gray level nonuniformity" as a gray level run length matrix-based feature showed statistically differences (p-values: 0.033 and < 0.001, respectively). Conclusions: Although COVID-19 manifests with lung involvement in the early stage, it can also cause systemic involvement, and the spleen may be one of its target organs. A decrease in the spleen size and parenchymal microstructure changes can be observed in the short follow-up time. It is hoped that the changes in the parenchymal microstructure will be demonstrated by a noninvasive method: texture analysis.