IgA vasculitis and acute hemorrhagic edema of infancy: a comparative analysis of two case reports

Introduction: Acute hemorrhagic edema of infancy (AHEI) is sometimes considered a milder variant of immunoglobulin A vasculitis (IgAV). This paper presents two clinical cases, aiming to explore the overlaps and differences between these two pathologies. Case report: A four-year-old initially presented with odynophagia, fever, and arthralgia. The diagnosis of IgAV was established following the development of purpura. A nontoxic five-month-old girl, initially diagnosed with viral exanthema, presented with fever, mild respiratory symptoms, and a maculopapular rash on the torso. Gradual progression to purpuric lesions and acral edema led to the diagnosis of AHEI. Discussion: While IgAV and AHEI share some clinical and histological features, their immunofluorescence patterns differ significantly. IgA deposition is observed in nearly 100% of IgAV cases but only in 10–35% of AHEI cases. This disparity may be attributed to the natural immaturity of the immune system in younger infants, potentially explaining the differences between these two diseases.