Transient Aortitis/Periaortitis with Spontaneous Resolution: Report of Four Cases.

Periaortitis is an inflammatory condition surrounding the aorta, classified as either idiopathic or secondary to well-defined causes; it typically requires treatment with glucocorticoids (GC) and/or immunosuppressants (IS). We report four cases of transient aortitis/periaortitis and summarize their characteristics and clinical courses. The four patients were all women (age range, 37-80 years). All patients had fever; three had dry cough and two experienced back or neck pain near the affected aortic site. At diagnosis, computed tomography (CT) revealed eccentric low-density areas in the periaortic space in all cases, involving the aortic arch or descending thoracic aorta in three patients. No carotid artery involvement was observed. One patient received low-dose GC for erythema nodosum, whereas the others did not receive GC or IS. The C-reactive protein (CRP) level was elevated in all cases. Symptoms and the CRP levels typically improved within approximately one month, and follow-up CT performed within approximately three months showed resolution in all cases. These four cases suggest the presence of a transient form of aortitis/periaortitis that improves without high-dose GC or IS. Notably, the thoracic aorta was predominantly affected, an unusual finding in chronic periaortitis. These cases may overlap with a spontaneous form of isolated aortitis and share informative features with transient perivascular inflammation of the carotid artery (TIPIC) syndrome and granulocyte colony-stimulating factor (G-CSF)-induced aortitis. Awareness of this condition may reduce unnecessary diagnostic workup and overtreatment; thus, additional case accumulation and further research are warranted to clarify its clinical spectrum and pathogenesis.