Pediatric Rheumatology Online Journal → July 2003 → Childhood Lupus→ Case Reports → Abstract #109

URTICARIAL VASCULITIS AS A PRESENTING FEATURE OF PEDIATRIC SLE

A. S. Padula, C. D. Rose

¹Pediatrics, duPont Children's Hospital, Thomas Jefferson University, Wilmington, DE, United States

Urticaria is an uncommon, yet important presenting lesion of vasculitis. Urticarial vasculitis (UV) has been associated with connective tissue diseases, IgM paraproteinemia, infections, serum sickness, and several drugs. When associated with hypocomplementemia (HUV) it may represent a distinct entity (HUVS) if Anti-C1q antibodies are present or SLE if they are absent. UV plaques persist for 24 to 72 hours and may depict residual purpuric hues, scaling, and hyperpigmentation. Lesions are typically painful or burning rather than pruritic. Systemic symptoms in the primary forms (HUVS) may include arthralgias, abdominal pain, obstructive lung disease, nephritis, and uveitis. Clinically, lesions resemble urticaria, but histologically they are a form of leukocytoclastic vasculitis (LCV). Direct immunofluorescence may reveal immunoglobulin and complement deposition in and around the blood vessel. UV should be suspected when individual painful hives persist for more than 24 hours or lead to pigmentation or show purpuric appearance. Poor response to antihistamines and features of systemic inflammation are also supportive.
We will describe a 14-year old Caucasian male who had 2 years of recurrent hives treated elsewhere as chronic ([quot>allergic[quot>) urticaria, elevated acute phase reactants, pan-hypocomplementemia, ANA of 1:640 (Sm+, low positive AntiDNA) and a severe membranous glomerulonephritis with nephrotic syndrome, [underline>but no anti-C1q antibody[/underline>. His cutaneous histology was that of a classic LCV but with the [underline>striking absence[/underline> of hemorrhage, a typical finding of LCV when it presents with the more conventional picture of [underline>palpable purpura[/underline>.
Summary: Although chronic urticaria is common in pediatrics, urticarial vasculitis is rare and commonly under-recognized. This case illustrates the diagnostic clues of UV and the differential diagnosis for the Pediatric Rheumatologist. We also stress the pathologic differences with other more common forms of LCV.