An Unusual Case of Bilateral Lower Extremity Edema in the Elderly: Immunoglobulin A (IgA) Vasculitis.

We report a case of a 74-year-old male who exhibited bilateral lower extremity edema over three days. Examination revealed no signs of heart, renal, or hepatic failure, and hypothyroidism was also ruled out. An outpatient regimen of 40 mg furosemide was initiated. At a 12-day follow-up, although the edema had improved, the patient had developed pain in both lower limbs, especially ankles, accompanied by numerous petechiae and erythemas, some of which had formed papules. Skin biopsy of the rash displayed leukocytoclastic vasculitis with immunoglobulin A (IgA) deposition within the vascular walls, leading to a diagnosis of IgA vasculitis. Given the rarity of IgA vasculitis in elderly patients and the broad spectrum of potential diagnoses related to bilateral lower extremity edema in this population, IgA vasculitis can be easily overlooked. While this case did not present with glomerulonephritis, regular renal function monitoring is recommended due to the prognostic implications of renal involvement in adult-onset IgA vasculitis.