A cutaneous sign of IgA-associated small dermal vessel leukocytoclastic vasculitis in adults (Henoch-Schonlein purpura)

Immunoglobulin-A–associated small-vessel vasculitis: A 10-year experience at the Massachusetts General Hospital

“…[36][37][38] 40,41 more chronic and severe skin disease, increased incidence of extracutaneous manifestations, and more benefit from early steroid therapy. 12 Similar to previously published findings, we found that the DIF pattern in HSP is typically characterized by IgA and in some cases also with C3 deposits. 42 The specificity of the finding of IgA deposits for diagnosing HSP has been reported as high as 89% to 100%.…”

“…The presence of two or more types of vasculitic lesions is another finding associated with systemic vasculitis, 21,22 but in our study, the reverse was observed as patients with two or more types of vasculitic lesions had a slightly smaller percentage of systemic vasculitis (65% vs 79%, P = .24). Clinical features of erythema elevatum diutinum 23 or a retiform or patterned purpura 12 were not documented in any of our patients. Two IgA-positive cases had biopsy-proven IgA glomerulonephritis.…”

“…4 The finding of vascular IgA deposition on direct immunofluorescence (DIF) examination of involved skin has been strongly associated with HSP, which has led many authors to advocate its use in the diagnosis of difficult cases. 2,[11][12][13] Some groups, including the Chapel Hill Consensus Group (CHHC), have even claimed that it is requisite for the diagnosis and incorporated IgA deposition into the definition of HSP. 10,14 However, others have pointed out the lack of specificity of this finding and suggested it be used as an adjunct to diagnosis, but not as a ''gold standard'' test.…”

Cutaneous Vasculitis Update: Small Vessel Neutrophilic Vasculitis Syndromes

“…A retiform or patterned purpura or skin necrosis, or retiform margins of other vasculitic lesions, are thought to be specific for HSP. 46 Other cutaneous lesions in HSP include petechiae, bullous lesions, and hemorrhagic FIGURE 2. Urticarial plaques that last longer than 24 hours and burn or sting more than they itch characterize urticarial vasculitis.…”

“…54 If DIF is done early in the course of the disease, isolated or predominate IgA deposits can be found in both involved and uninvolved vessels. 46,54,55 In addition to isolated or predominate IgA vascular deposits, the finding of two or more of clinical features such as age #20 years, gastrointestinal involvement (colicky pain or hematochezia), upper respiratory tract infection prodrome, hematuria, and/or renal biopsy showing mesangioproliferative glomerulonephritis with or without IgA deposits, increases the sensitivity and specificity for the diagnosis of HSP. 14,56 Isolated IgA vascular deposits (or with C3) are suspected to be specific for HSP.…”