Posterior lumbar subcutaneous edema as the rare sign of IgA vasculitis (Henoch-Schönlein purpura): A case of a child.

Posterior lumbar subcutaneous edema (PLSE) is often found on MRI in adults with obesity or various lumbar conditions. We report a case of a 6-year-old boy with IgA vasculitis (Henoch-Schönlein purpura) along with PSLE observed on CT and MRI. The finding is markedly rare in patients with IgA vasculitis, with only limited cases previously reported in the literature. The edema was symmetrically localized along the erector spine muscle with a smooth margin. These findings differed from the irregularly accumulated edema observed in some adult cases. PLSE should not be overlooked as a nonspecific finding. When symmetrical and circumscribed PLSE is found in children, IgA vasculitis should be added to differential diagnosis in PLSE.