Histologic Clues to Diagnosis of Vasculitic Disorders
Findings | Possible Diagnoses |
|---|---|
Predominantly nonnecrotizing granulomatous inflammatory infiltrate with lymphocytes, macrophages, and multinucleated giant cells | Primary angiitis of the central nervous system (certain types) |
Fibrinoid vascular necrosis of the vessel wall with a mixed infiltrate consisting of various combinations of leukocytes and lymphocytes | Eosinophilic granulomatosis with polyangiitis (EGPA) Granulomatosis with polyangiitis (GPA) Immune complex–associated vasculitis |
IgA deposits* | Immunoglobulin A–associated vasculitis (formerly Henoch-Schönlein purpura) |
Scant or complete absence of immunoglobulins and complement deposition in the vessel walls*† | EGPA GPA MPA |
* These observations are noted using immunofluorescence staining. | |
† Disorders thus characterized are called pauci-immune vasculitic disorders. | |