A case report of a 14-year-old male patient with large vessel vasculitis following COVID-19.

Most reported cases of large vessel vasculitis (LVV) following coronavirus disease 2019 (COVID-19) have involved adults, with paediatric cases being rare. We present the case of a 14-year-old boy who developed LVV following COVID-19. Initially, he presented with fever and cough, and nasopharyngeal polymerase chain reaction testing confirmed COVID-19. His symptoms spontaneously resolved without specific COVID-19 treatments. However, 10 days after contracting COVID-19, his fever recurred and his inflammatory markers were significantly elevated. His condition did not meet the criteria for Kawasaki disease or multisystem inflammatory syndrome in children associated with COVID-19. Contrast-enhanced computed tomography revealed arterial wall thickening in the aorta and carotid arteries, indicative of LVV. Upon initiation of high-dose immunoglobulin therapy and aspirin, his fever subsided and his inflammatory markers and imaging findings normalised. Differential diagnosis ruled out infections, immune disorders, and Takayasu arteritis (TAK), a common cause of aortitis in children. Over a 1-year follow-up period, there were no recurrence and no stenotic lesions in large vessels. This finding suggests that the patient experienced transient LVV following COVID-19. Cytokine profile analysis performed before and after treatment revealed elevated levels of interleukin (IL)-6, IL-8, and IL-12/IL-23p40, typically associated with the active phase of TAK. Importantly, IL-17A and tumour necrosis factor-α levels were normal, as elevations in these cytokines have been linked to TAK recurrence. Notably, some cases of LVV following COVID-19 do not respond well to treatment; further research, including case accumulation and cytokine profile analysis, is needed to better predict prognosis.