Giant Cell Arteritis after COVID-19 Vaccination with Long-Term Follow-Up: A Case Report and Review of the Literature.

Giant cell arteritis (GCA) is a chronic vasculitis that primarily affects the elderly, and can cause visual impairment, requiring prompt diagnosis and treatment. The global impact of the coronavirus disease 2019 (COVID-19) pandemic has been substantial. Although vaccination programs have been a key defense strategy, concerns have arisen regarding post-vaccination immune-mediated disorders and related risks. We present a case of GCA after COVID-19 vaccination with 2 years of follow-up. A 69-year-old woman experienced fever, headaches, and local muscle pain two days after receiving the COVID-19 vaccine. Elevated inflammatory markers were observed, and positron emission tomography (PET) revealed abnormal uptake in the major arteries, including the aorta and subclavian and iliac arteries. Temporal artery biopsy confirmed the diagnosis of GCA. Treatment consisted of pulse therapy with methylprednisolone, followed by prednisolone (PSL) and tocilizumab. Immediately after the initiation of treatment, the fever and headaches disappeared, and the inflammation markers normalized. The PSL dosage was gradually reduced, and one year later, a PET scan showed that the inflammation had resolved. After two years, the PSL dosage was reduced to 3 mg. Fourteen reported cases of GCA after COVID-19 vaccination was reviewed to reveal a diverse clinical picture and treatment response. The time from onset of symptoms to GCA diagnosis varied from two weeks to four months, highlighting the challenge of early detection. The effectiveness of treatment varied, but was generally effective similarly to that of conventional GCA. This report emphasizes the need for clinical vigilance and encourages further data collection in post-vaccination GCA cases.

Report of Two Contrasting Cases of Epstein-Barr Virus-Associated Hemophagocytic Lymphohistiocytosis: Comparison to Infectious Mononucleosis and Flow Cytometric Analysis of Bone Marrow.

Purpose: This study aims to investigate the characteristics of Epstein-Barr virus associated-hemophagocytic lymphohistiocytosis (EBV-HLH) and HLH caused by a severe form of infectious mononucleosis (IM-HLH) compared to IM by EBV, and thus also to assist in early diagnosis and providing appropriate treatment. Methods: Data for this analysis were collected from patients at the Department of General Medicine, Nara Medical University, between April 1, 2012, and August 1, 2020. EBV infection was diagnosed using clinical presentation and laboratory tests. HLH diagnosis followed the HLH-2004 protocol, supplemented by plasma EBV DNA detection. A range of clinical and laboratory parameters were collected, including age, sex, clinical outcomes, blood cell counts, hemoglobin, platelets, and various serum values. Plasma EBV DNA levels and flow cytometric analysis (FCM) of bone marrow were performed for HLH cases. Results: Among 1850 hospitalized patients, 14 cases were identified, including 2 HLH cases and 12 IM cases. Comparative analysis revealed distinctive features of HLH, including lower lymphocyte and platelet counts and higher levels of ferritin, soluble interleukin 2 receptor (sIL-2R), and D dimer compared to IM. Notably, one HLH case responded well to corticosteroid monotherapy, while the other case did not, resulting in a fatal outcome. Detection of a cluster of CD5-CD7 lymphocytes in bone marrow is a hallmark of EBV-HLH and useful to distinguish from IM-HLH. Conclusion: This study underscores the importance of early differentiation among EBV-HLH, IM-HLH, and IM in adults to guide appropriate treatment strategies. While specific laboratory markers help distinguish HLH from IM, a more detailed analysis of FCM is crucial for precise diagnosis of HLH cases and tailored therapeutic interventions.